HK1112949A - Non-combustible reinforced cementitious lightweight panels and metal frame system for shear walls - Google Patents

Abstract

A vertical shear wall system including vertical metal framing members, for example, C-joists, U-joists, open web joists, or other metal frame systems that support a reinforced, lightweight, dimensionally stable SCP panel. The shear wall system is non-combustible, water durable, mold and rot resistant, termite resistant and is capable of resisting shear loads equal to or exceeding shear loads provided by plywood or oriented strand board panels. The panels employ one or more layers of a continuous phase resulting from the curing of an aqueous mixture of inorganic binder, for example, calcium sulfate alpha hemihydrate, hydraulic cement, an active pozzolan and lime. The continuous phase is reinforced with glass fibers and contains lightweight filler particles, for example, ceramic microspheres.

Description

Non-combustible reinforced cementitious lightweight panel and metal frame system for shear walls

Technical Field

The present invention relates generally to a shear wall system for use in residential and commercial buildings comprising a metal frame and a lightweight structural cementitious panel (referred to herein as an SCP panel). More particularly, the present invention relates to a non-combustible shear wall system having panels mechanically or adhesively secured to a steel frame shear wall system. The panels provide shear resistant bulkheads and axial load bearing shear wall elements. The system provides the following advantageous performance attributes when used with steel wall framing: non-flammability, water resistance, mold resistance, high specific strength and rigidity, economy of building design with increased assembly speed, and reduced foundation size due to reduced building weight.

Background

Shear walls play an important role in residential and commercial buildings. If one considers a simple box structure with panels fastened to the framework, it can be seen that a strong side force (e.g., wind pressure) acting on one side of the box will tend to force the side walls resisting the force from a rectangular shape to a parallelogram. Not all of the cover panels are able to resist such forces, nor are they very resilient, and some of the cover panels will be damaged, particularly at those points where the panels are fastened to the framework. Where shear strength must be exhibited, the cover plate is measured to determine the load that the panel can resist when within an allowable range of deflection and without damage.

The shear rating is generally based on testing three identical 8 x 8 foot (2.44 x 2.44m) assemblies, i.e., panels fastened to a frame. One edge is fixed in place and at the same time a side force is applied to the free end of the assembly until it can no longer be loaded and the assembly is damaged. The measured shear strength will vary depending on the thickness of the panel and the size and spacing of the fasteners used in the assembly. For example, it would be desirable for a typical assembly, such as a nominally 1/2 inch (12.7mm) thick plywood fastened by 8d nails (see nail description below) spaced 6 inches (152.4mm) on the perimeter and 12 inches (304.8mm) within the perimeter to a nominally 2x 4 inch (50.8 x 101.6mm) wooden stud (in the center) spaced 16 inches (406.4mm) prior to failure, to exhibit a shear strength of 720lbs/ft (1072 kg/m). (note that the measured strength will vary as fastener size and spacing changes, as provided by the ASTM E72 test.) this final strength will be reduced by a safety factor (typically a factor of 3) to set the design shear strength for the panel.

The cover panels used in situations where shear ratings must be met are typically plywood or Oriented Strand Board (OSB), which is composed of multiple pieces of wood glued together. These panels can provide the required shear strength, but each is flammable and none is durable when exposed to water. Panels made of hydraulic cement will be water resistant, but much heavier than wood panels and insufficient shear strength. To address some of these problems, structural cement panels (SCP or SCP panels) have been developed.

U.S. patent No. 6,620,487 to Tonyan et al, which is incorporated herein by reference in its entirety, discloses a reinforced, lightweight and dimensionally stable structural cement panel (SCP or SCP panel) that is capable of resisting shear loads equal to or exceeding those provided by plywood or oriented strand board panels when fastened to a frame. The panels employ a core having a continuous phase resulting from the curing of an aqueous mixture of: calcium sulphate alpha hemihydrate, hydraulic cement, active pozzolan and lime, the continuous phase being reinforced with alkali-resistant glass fibres and containing ceramic microspheres or a blend of ceramic and polymer microspheres, or being formed from an aqueous mixture having a weight ratio of water to reactive powder of from 0.6/1 to 0.7/1, or a combination of these. At least one outer surface of the panel may include a cured continuous phase reinforced with glass fibers and containing sufficient polymer spheres to improve nailing capability, or made with a water to reactive powder ratio to provide an effect similar to polymer spheres, or a combination of these.

Bonen, U.S. patent No. 6,241,815, which is incorporated herein by reference in its entirety, also discloses formulations that can be used for SCP panels.

United states patent application No. 10/666,294, which is incorporated herein by reference, discloses a multi-layer process for producing structural cement panels (SCPs or SCP panels) and SCPs produced by such process. After the process of initially depositing a loosely distributed and chopped layer of fiber or slurry on a moving web, the fiber is deposited on a layer of slurry. The embedment device mixes the newly deposited fibers into the slurry, after which an additional layer of slurry and then chopped fibers are added, followed by embedment again. The process is repeated for each layer of the panel as needed.

However, while the use of SCP panels on wooden frames is an improvement over the use of plywood, it would be desirable to have a system that is further non-flammable.

For use in construction, the SCP panels should meet building code standards for shear resistance, load capacity, water induced expansion and burn resistance as measured by recognized tests such as ASTM E72, ASTM E661 and ASTM C1185 or equivalents applied to structural plywood sheets. SCP panels were also tested for non-flammability at ASTM E-136-plywood does not meet this test.

The SCP panel should be able to be cut by a circular saw used to cut wood.

The SCP panel should be dimensionally stable when exposed to water, i.e. it should swell as little as possible, preferably less than 0.1%, as measured by ASTM C1185.

The SCP panel should provide an engageable substrate for the exterior finished system.

The SCP panel should be non-flammable, as determined by ASTM E136.

After 28 days of cure, the dry density was 65lb/ft³(1041kg/m³) To 90lb/ft³(1442kg/m³) Or 65lb/ft³(1041kg/m³) To 95lb/ft³(1522kg/m³) The flexural strength (flexural strength) of a 0.75 inch (19mm) thick SCP panel after soaking in water for 48 hours should be at least 1000psi (7MPa), for example at least 1300psi (9MPa), preferably at least 1650psi (11.4MPa), more preferably at least 1700psi (11.7MPa), as measured by ASTM C947. The panel should retain at least 75% of its dry strength.

Because the thickness of the sheet affects its physical and mechanical properties (e.g., weight, load carrying capacity, peel strength, etc.), the desired properties vary depending on the thickness of the sheet. Thus, desirable properties that should be met by a shear rated panel having a nominal thickness of 0.5 inches (12.7mm) include the following.

The panel should have a final load capacity of greater than 550lb (250kg) under static loading, a final load capacity of greater than 400lb (182kg) under impact loading, and a deflection of less than 0.078 inch (1.98mm) under both static and impact loading with a 200lb (90.9kg) load when tested over a 16 inch (406.4mm) span on center according to ASTM E661 and American Plywood Association (APA) test method S-1.

The nominal peel shear strength of a 0.5 inch (12.7mm) thick panel, as measured by ASTM E72 testing using the above-described nail sizes and spacing, should be at least 200lb/ft (about 300kg/m), typically at least 720lb/ft (1072 kg/m). The weight of a 4 x 8 foot and 1/2 inch thick panel (1.22 x 2.44m, 12.7mm thick) should not exceed 99lb (44.9kg) or 104lb (47kg), and preferably not exceed about 96 or 85lb (about 44 or 39 kg).

The panel should be capable of being cut by a circular saw used to cut wood.

The panels should be able to be fastened to the frame with nails or screws.

The panel should be machinable so that a tongue and groove edge can be created in the panel.

The panel should be dimensionally stable when exposed to water, i.e. it should swell as little as possible, preferably less than 0.1%, as measured by ASTM C1185.

The panels should not be biodegradable or subject to insect attack or corrosion.

The panel should provide an engageable substrate for the outer finished system.

The panel should be non-flammable, as determined by ASTM E136.

After 28 days of cure, the dry density does not exceed 65 to 95lb/ft³(1041 to 1520kg/m³) Should have a flexural strength of at least 1700psi (11.7MPa), preferably at least 2500psi (17.2MPa), as measured by ASTM C947, after soaking in water for 48 hours. The panel should retain at least 75% of its dry strength.

It should be apparent that plywood and OSB panels meet some, but not all, of the above performance characteristics.

There is a need for an overall frame and shear wall system that is economical, easy to assemble, durable, and non-combustible.

Disclosure of Invention

The present invention relates to a system for residential and light commercial construction comprising a metal frame and a light SCP panel shear wall. The shear wall is made of a mixture of an inorganic binder and a lightweight filler. The combination of the metal frame and the SCP panel is chosen to achieve the synergy of a completely non-combustible shear wall system. By a completely non-flammable horizontal shear barrier on a lightweight cold rolled metal frame is meant a system in which all elements pass ASTM E-136. For example, the shear wall system may include SCP panels used with metal shear wall framing systems that employ any standard light gauge steel C-channels, U-channels, I-beams, square tubes, and lightweight prefabricated building sections.

When used in walls, 0.5 inch (12.7mm) thick panels typically have a nominal peel shear strength of at least 720 lb/linear foot (1072 kg/linear meter) as measured by ASTM E72 testing using the appropriate metal studs, fasteners, stud spacing and fastener spacing.

Compared with a load-bearing masonry shear wall system, the SCP vertical shear wall diaphragm system can have higher specific peel shear strength and rigidity. Specific peel shear strength is defined as the unit weight (in pounds per square foot (lb/ft)) of the shear wall system²) In units) to meet a particular peel shear requirement (in pounds per linear foot).

For a given nominal wall peel shear strength specification in the range of 200-. For example, for a shear wall having a nominal thickness of 4 ", an SCP/steel frame shear wall will weigh about 4 psf. A 4 "nominal thickness masonry wall (using a lightweight CMU) will weigh about 30 psf. Thus, for a 4 "wall with a nominal peel shear strength requirement of 700plf, the specific wall peel strength of SCP is 175plf/psf and that of CMU wall is 23.3 plf/psf. The specific wall peel strength advantage of SCP walls over CMU is over the full range of peel strengths considered (nominally 200-.

The present system with vertical shear spacers on a lightweight cold rolled metal frame is also typically water resistant. Preferably, the vertical shear diaphragm load carrying capacity of the inventive system will not be reduced by more than 25% (more preferably, will not be reduced by more than 20%) when exposed to water for 24 hours in a test in which a 2 inch head of water is maintained over a horizontally oriented diaphragm of 3/4 inch thick SCP panels fastened on a 10 foot by 20 foot metal frame. In this test, the 2 inch head was maintained by checking and replenishing water at 15 minute intervals. The system is then reoriented in the vertical direction and the vertical shear diaphragm load carrying capacity of the system is measured.

Preferably, the inventive system will not absorb more than 0.7 pounds per square foot of water when exposed to water for 24 hours in a test in which a 2 inch head of water is maintained over an 3/4 inch thick SCP panel fastened on a 10 foot by 20 foot metal frame. In this test, the 2 inch head was maintained by checking and replenishing water at 15 minute intervals.

Also, combining a non-combustible SCP panel with a metal frame creates a complete system that resists expansion due to moisture. Preferably, in the present system, a 10 foot wide by 20 foot long by 3/4 inch thick SCP panel diaphragm attached to a 10 foot by 20 foot metal frame will not expand by more than 5% when exposed to a 2 inch head of water maintained over the SCP panel fastened to the metal frame for 24 hours. In this test, the 2 inch head was maintained by checking and replenishing water at 15 minute intervals.

Also, the present shear wall system with vertical partitions of SCP panels on a metal frame creates a mold resistant shear wall system. Preferably, each component of the system of the present invention meets ASTM G-21 testing, wherein the system achieves an approximate rating of 1, and meets ASTM D-3273 testing, wherein the system achieves an approximate rating of 10. Preferably, the system of the present invention supports substantially zero bacterial growth when clean.

Another preferred attribute of the present shear wall system with horizontal partitions of SCP panels on metal frames is that it is preferably not edible by termites.

A potential advantage of the present system is that, because it is lightweight and strong, the combination of the present shear wall system with vertical partitions of 3/4 or 1/2 inch thick SCP panels on a metal frame allows for efficient use of building volume for a given building footprint to allow for maximization of the building volume for that given building footprint. Thus, the present system may allow for more efficient building volume, allowing for the use of more shear walls for indoor clearance or even a greater number of shear walls in planned areas with building height restrictions.

Building codes and design criteria contain minimum thickness requirements for masonry shear walls. The minimum nominal thickness of a masonry (CMU) shear wall in a single story building is 6 inches. The minimum thickness of a masonry shear wall (CMU) for buildings above 1 floor is 8 inches. SCPs with steel frame shear walls do not have similar minimum requirements and can be designed to be less than 8 inches thick for multi-storey buildings and less than 6 inches thick for single-storey buildings, depending on the established engineering principles. The use of 6 inch thick SCP/steel frame shear walls instead of 8 inch thick masonry shear walls can result in a significant increase in the available building volume.

For example, we will consider a 3-story 30,000 square foot building with 10,000 square feet per floor, with a floor-to-ceiling height of 10 feet. Assume that the building is 100 square feet, so that the perimeter is 400 linear feet. We will further assume that there needs to be 100 linear feet of shear wall in the building core to meet the shear requirements of the building design. The use of 6 inch thick SCP/steel frame shear walls (including perimeter walls) instead of 8 inch thick masonry shear walls (including perimeter walls) resulted in an increase of 2500 cubic feet of usable building volume in the 3-story 30,000 square foot example.

As in the above example, a building using an SCP combined with a steel frame as a shear wall will have a reduced dead load compared to a building using a CMU wall having the same thickness and height as a shear wall. For example, we will consider a building that requires 200 linear feet of shear wall with a nominal peel shear strength requirement of 500plf as a shear wall, where a 4 "wide shear wall is used and the wall height is 8 feet. In this case, the use of SCP in combination with metal framing reduced the dead load of the shear wall in the building by 41,600 pounds compared to the use of CMU shear walls. This reduction in deadload may result in a reduction in the size of structural components in lower levels of the building, or a reduction in the size of the building foundation.

The lightweight nature of this system generally avoids the deadload associated with masonry or concrete wall systems. Less dead load also allows for the construction of structures of comparable size on less stable soils with relatively low bearing capacity.

Unlike plywood, the present system potentially has the advantage of being potentially non-directional. In other words, the panels of the present system can be placed with their long dimension parallel or perpendicular to the metal joists of the frame without loss of strength or load bearing characteristics. Thus, the ability of the system to support both dead and live loads without breaking is the same regardless of the orientation of the SCP panel on the metal frame.

Typical composites for embodiments of the panels of the present invention that achieve a combination of low density, improved flexural strength and nailability/cuttability comprise an inorganic binder (examples-gypsum-cement, portland cement, or other hydraulic cement) having distributed throughout the thickness of the panel selected glass fibers, lightweight fillers (examples-uniformly distributed hollow glass microspheres, hollow ceramic microspheres, and/or perlite), and a high efficiency plasticizer/high proportion water reducing admixtures (examples-polynaphthalenesulfonate, polyacrylate, etc.).

The system of the present invention may employ single or multiple layer SCP panels. In a multi-layer SCP panel, the layers may be the same or different. For example, an SCP panel may have an inner layer having a continuous phase and at least one outer layer having a continuous phase on each opposing side of the inner layer, where the at least one outer layer on each opposing side of the inner layer has a higher percentage of glass fibers than the inner layer. This has the ability to harden, strengthen and toughen the panel.

Typical panels are made from a mixture of water and inorganic binder with selected glass fibers, lightweight ceramic microspheres, and superplasticizers in the mixture.

Other additives such as accelerating and retarding admixtures, viscosity control additives may be added to the mixture as needed to meet the requirements of the manufacturing process involved.

The single or multi-layer panel may also be provided with a sheet of mesh, such as a fiberglass mesh, if desired.

In embodiments having multiple (two or more) layers, the composition of each layer may be the same or different. For example, the multi-layer panel structure can be formed to contain at least one outer layer having improved nailability and cuttability. This is provided by using a higher ratio of water to reactive powder (defined below) to make the outer layer relative to the panel core. A smaller thickness of skin coupled with a smaller dosage of polymer content may improve nailability without necessarily failing the non-flammability test. Of course, high dosage polymer content can result in products that fail non-flammability tests.

Glass fibers may be used alone or in combination with other types of non-combustible fibers (e.g., steel fibers).

As previously discussed, there is a need for a lightweight non-combustible shear wall system to replace wood frames covered by plywood or OSB shear wall panels. There is also a need for a lightweight and economical alternative to shear wall systems constructed from poured concrete or unit masonry.

The SCP panel may be attached to the stud mechanically or by adhesive. The attachment of the SCP panel to the pillar may be effected synthetically, such that the pillar and panel cooperate to carry greater loads than a single frame.

Drawings

FIG. 1 is a perspective view of a single layer SCP panel used with a metal frame in the non-combustible shear wall system of the present invention.

Fig. 2 is a schematic side view of a metal C-pillar for use with a Structural Cement Panel (SCP) panel in the non-combustible shear wall system of the present invention.

Fig. 3 is a perspective view of a metal stud wall in a non-combustible shear wall system of the present invention employing spacer members and studs of a typical construction suitable for use with Structural Cement Panel (SCP) panels.

FIG. 4 is a perspective view of a metal stud wall with a SCP panel attached to one side.

FIG. 5 shows a schematic side view of a multi-layer SCP panel used with a metal frame in a non-combustible shear wall system of the present invention.

FIGS. 5A-5C illustrate a typical design and size of a tongue and groove employed in an 3/4 inch (19.1mm) thick SCP panel (dimensions in inches).

FIG. 6 is a fragmentary cross-sectional view of the SCP panel of FIG. 1 supported on the C-shaped stud metal frame of FIG. 1 in a non-combustible shear wall system of the invention.

FIG. 7 is a perspective view of a metal stud wall with respective SCP panels attached to opposite sides.

Fig. 8 shows a combined metal (e.g., steel) base framework.

Fig. 9 shows the attachment of the C-shaped joist metal frame members to the top beam.

FIG. 10 shows an enlarged view of a portion of the frame of FIG. 8.

FIG. 11 shows a test SCP panel base system configuration attached to the metal frame of FIG. 8.

Fig. 12, 13, 14 and 15 show enlarged views of various portions of the substrate of fig. 11.

Fig. 16 shows the frame of fig. 8 with the attached shear wall of fig. 9 installed on a shear wall bulkhead test apparatus.

FIG. 17 shows an enlarged view of a portion of the apparatus of FIG. 16.

FIG. 18 shows experimental load versus deflection data from an example employing the base diaphragm test apparatus of FIG. 16.

FIG. 19 shows a photograph of a SCP panel and metal frame shear wall mounted on the test device of FIG. 16 under design load.

FIG. 20 shows a photograph of a SCP panel and metal frame shear wall mounted on the test device of FIG. 16 in a broken state.

FIG. 21 is a diagrammatic elevation view of a device suitable for use in performing the process for making an SCP panel.

FIG. 22 is a perspective view of a slurry feed station of the type used in the process for making SCP panels.

FIG. 23 is a fragmentary top plan view of an embedded device suitable for use with the process for making an SCP panel.

FIG. 24 shows the substrate architecture used in the AISI TS-7 test.

FIG. 25 shows one of the SCP substrates used in the AISI TS-7 test.

FIG. 26 shows the test equipment used in the AISI TS-7 test.

FIG. 27 shows data from AISI TS-7 cantilever substrate diaphragm testing using 3/4 inch SCP panels with 4 inch-12 inch fastening schedule.

FIG. 28 shows data from AISI TS-7 cantilever base diaphragm testing using 3/4 inch SCP panels with 6 inch-12 inch fastening schedule compared to 3/4 inch plywood.

FIG. 29 shows data from AISI TS-7 cantilever substrate diaphragm testing using an 3/4 inch SCP panel with adhesive.

Detailed Description

FIG. 1 is a schematic side view of a single layer SCP panel 4 for use with a metal frame in the system of the present invention. The primary raw materials used to make such SCP panels are inorganic binders (e.g., calcium sulfate alpha hemihydrate, hydraulic cements, and pozzolanic materials), lightweight fillers (e.g., one or more of perlite, ceramic microspheres, or glass microspheres), and high-efficiency plasticizers (e.g., polynaphthalenesulfonates and/or polyacrylates), water, and optional additives.

Metal frame

The frame may be any metal (e.g., steel or galvanized steel) framing system suitable for supporting shear walls. A typical frame includes C-shaped posts with openings therein to pass lead pipes and electrical wiring through the shear wall.

A typical C-shaped upright 6 is shown in figure 2. The C-shaped column has a column web and an upper column foot projecting from the joist web and a lower joist foot projecting from the column web. Typically, the stud web has one or more openings through the stud web to pass utility lines through the shear wall.

FIG. 3 shows a typical system that may be employed in the present shear wall system. FIG. 3 shows a metal stud wall "skeleton" 10 made in accordance with U.S. patent No. 6,694,695 to Collins et al, which is incorporated herein by reference, and adapted to be combined with SCP panels to achieve the shear wall system of the present invention. This metal frame system is provided for illustration purposes only, as other metal frames may also be employed. In this embodiment, the metal stud wall framework 10 includes a lower track 12, a plurality of metal studs 20, and at least one spacer member 40. The SCP panel 4 (fig. 1) can be fastened to one or both sides of the metal upright 20 in any known manner to close off the wall and form the outer surface of the wall.

Fig. 4 is a perspective view of a metal stud wall 5 with an SCP panel 4 attached to one side.

Us patent 6,694,695 to Collins et al discloses that while wooden studs are formed of solid wood (typically having a nominal cross-sectional dimension of 2 inches by 4 inches), the much greater structural strength of metal (e.g., 20 gauge galvanized steel) allows construction studs that are not solid but hollow and have a channel or "C-shaped" cross-section to be employed. In order to comply with construction plans and construction materials that have been developed over the years based on the use of wooden studs with specific cross-sectional dimensions, commercially available metal studs are constructed with the same external dimensions as wooden studs have been manufactured over the years. Specifically, metal studs are typically formed from sheet metal that is bent to enclose a cross-sectional area nominally 2 inches by 4 inches.

For ease of manufacture, the metal studs are formed from sheet metal bent into a generally "U" shaped cross-section with a pair of narrower sides bent at right angles to the web or base on either side of a relatively wider central web. The web typically has a uniform nominal width of 4 inches or 3.5 inches, and the sides of the U-shaped studs typically extend from the web a nominal distance of 2 inches. To enhance structural rigidity, the edges of the sides of the metal studs are typically folded into planes parallel to and spaced from the plane of the web. These upturned edges of the side walls thereby form edge lips which are typically 1/4 to 1/2 inches in width. The completed stud thus has a substantially "C-shaped" cross-section.

The outer dimensions of the metal framing members and studs and the weight or gauge of the members or studs may vary. Typically, the sections are made approximately 4 inches wide by 2 inches deep, corresponding to the width and depth of the timber frame and stud sections, in which case the lip may extend 1/4 to 1/2 inches from the side of the stud. The 18 to 20 gauge metal can be used for light residential and commercial wall construction. Heavier range metal gauges are used in certain residential and commercial frameworks and particularly multi-story commercial buildings.

The top cross member extending along the top of the columns in the interior construction wall building has a U-shaped configuration. They are each formed with a horizontally disposed web from which a pair of side walls depend vertically from the web on opposite sides of the web. The side walls surround the sides of the vertical posts so that the upper ends of the posts extend vertically into the recessed and downwardly facing channels formed by the top beams. The spacing of the studs along the length of the beam is typically 16 or 24 inches.

Various methods have been developed for connecting and fastening metal frames and wall studs. At the most basic level, metal studs are inserted into metal tracks and fastened within the metal tracks by drilling and screwing from the outer wall of the track into the adjoining metal stud. Similarly, commercially available means for interconnecting metal framing members (e.g., joint brackets, shear connectors, and board connectors) typically use screws and bolts that are applied inward from the outside of the rail or stud members.

Metal stud and frame members have been modified to include saw or punch slots, tabs and brackets which are desirable to facilitate interconnection of such stud and frame members to adjoining stud and frame members and/or to cross bars and other non-frame members to reinforce the stud and frame members. Currently known connectors for joining and interconnecting metal studs (including brackets, plates and joint connectors) are typically drilled and screwed in the field. Drilling and screwing loose connectors poses a safety risk to workers, as connectors tend to be small and light, and are therefore easily grasped and rotated by hand drills.

5,687,538 discloses a structural framing member having a C-shaped cross-section consisting of a major planar surface and two planar side walls at right angles and suitable for use with the present shear wall system. The sidewall exhibits an inwardly turned lip formed generally parallel to the base. The ability to increase the section of the metal truss joist by embossing longitudinal stiffeners perpendicular to the top and bottom side walls, said stiffeners having a minimum depth of 0.01 "(0.025 cm) and being continuous along the face of the main flat surface throughout the length of the section. By bridging these longitudinal stiffeners with (but not limited to) diagonally stamped stiffeners, a series of abutting geometries have been established between the longitudinal chords to increase the stiffness of the web via the abutting geometry stiffeners, which will carry loads through axial deformation rather than pure shear deformation.

Calcium sulfate hemihydrate

Calcium sulfate hemihydrate useful in the panels of the present invention is formed from gypsum ore, a naturally occurring mineral (calcium sulfate dihydrate CaSO)₄·2H₂O). Unless otherwise indicated, "gypsum" will refer to the dihydrate form of calcium sulfate. After mining, the gypsum is heat treated to form a settable calcium sulfate, which may be anhydrous, but more typically is hemihydrate (CaSO)₄·1/2H₂O). To achieve the usual end use, the settable calcium sulfate reacts with water to set by forming dihydrate (gypsum). Hemihydrate has two recognized forms, designated alpha hemihydrate and beta hemihydrate. These hemihydrate compounds are selected for various applications based on their physical properties and cost. The two forms react with water to form the dihydrate of calcium sulfate. By hydration, alpha hemihydrate is characterized by the formation of rectangular side crystals of gypsum, while beta 0 hemihydrate is characterized by the hydration to produce needle-shaped crystals of gypsum, which typically have a large aspect ratio. In the present invention, either or both of the alpha or beta forms may be used depending on the mechanical properties desired. Beta hemihydrate forms a less dense microstructure and is preferred for low density products. Alpha hemihydrate forms denser microstructures with higher strength and density than those formed from beta hemihydrate. Thus, alpha hemihydrate can be used in place of beta hemihydrate to increase strength and density, or they can be combined to adjust properties.

Typical examples of inorganic binders used to make the panels of the present invention consist of hydraulic cement (e.g., portland cement, high alumina cement, portland cement blended with pozzolan, or mixtures thereof).

Another typical example of an inorganic binder used to make the panels of the present invention includes a blend containing calcium sulfate alpha hemihydrate, hydraulic cement, pozzolan, and lime.

Hydraulic cement

ASTM defines "hydraulic cement" as follows: a cement which sets and hardens by chemical interaction with water and which is capable of such actions underwater. There are several hydraulic cements used in the construction and building industry. Examples of hydraulic cements include portland cement, slag cement (e.g., blast furnace slag cement and sulfate-rich cement), calcium sulfoaluminate cement, high alumina cement, expansive cement, white cement, and rapid setting and hardening cement. Although calcium sulphate hemihydrate sets and hardens by chemical interaction with water, it is not included within the broad definition of hydraulic cement in the context of the present invention. All of the aforementioned hydraulic cements may be used to make the panels of the present invention.

The most popular and widely used ethnicity of closely related hydraulic cements is known as portland cement. ASTM defines "portland cement" as a hydraulic cement produced by crushing clinker which consists essentially of hydraulic calcium sulfate, usually containing one or more forms of calcium sulfate as a broken off impurity. To make portland cement, a homogeneous mixture of limestone, coarse tartaric (argalliciou) rock and clay is burned in a kiln to produce a clinker, which is then further processed. As a result, the following four main phases of portland cement are produced: tricalcium silicate (3 CaO. SiO)₂Also known as C₃S), dicalcium silicate (2 CaO. SiO)₂Is called C₂S), tricalcium aluminate (3 CaO. Al)₂O₃Or C₃A) And tetracalcium aluminoferrite (4 CaO. Al)₂O₃·Fe₂O₃Or C₄AF). Other compounds present in small amounts in portland cement include calcium sulfate and other double salts of alkali sulfates, calcium oxide and magnesium oxide. Of the various recognized classes of portland cement, type III portland cement (ASTM classification) is preferred for making the panels of the present invention because its fineness has been found to provide higher strength. Other recognized classes of hydraulic cements, including slag cements (e.g., blast furnace slag cement and sulfate-rich cement), calcium sulfoaluminate cement, aluminous cement, expansive cement, can also be successfully used to make the panels of the present inventionWhite cements, fast setting and hardening cements (e.g., set adjusting cements and VHE cements), and other portland cement classes. Slag cements and calcium aluminate sulfide cements have low basicity and are also suitable for making the panels of the present invention.

Fiber

Glass fibers are commonly used as insulation materials, but they have also been used as reinforcement materials with various matrices. The fibers themselves provide tensile strength to the material, which may otherwise suffer brittle failure. Fibers may break under loading, but a common mode of failure for composites containing glass fibers is caused by degradation and damage of the bond between the fiber and the continuous phase material. Thus, such joining is important if the reinforcing fibers are used to maintain the ability to increase ductility over time and strengthen the composite. It has been found that glass fibre reinforced cement loses strength over time, which has been attributed to the attack of the glass by lime, which occurs when the cement sets. One possible way to overcome such erosion is to cover the glass fibers with a protective layer (e.g., a polymer layer). Generally, such protective layers are resistant to attack by lime, but it has been found that strength is reduced in the panels of the invention, and therefore protective layers are not preferred. One more expensive way to limit lime erosion is to use special alkali resistant Glass fibers (AR Glass fibers), such as Nippon Electric Glass (NEG) 350Y. Such fibers have been found to provide excellent bond strength to the matrix and are therefore preferred for use in the panels of the present invention. The glass fibers are monofilaments having a diameter of from about 5 to 25 microns, and typically about 10 to 15 microns. The filaments are typically combined into 100 filament strands that can be bundled into rovings containing about 50 strands. The strands or rovings will typically be chopped into suitable filaments and filament bundles, for example about 0.25 to 3 inches (6.3 to 76mm) long, typically 1 to 2 inches (25 to 50 mm).

It is also possible to include other non-combustible fibers in the panels of the invention, for example, the metal fibers may also be a potential additive.

Pozzolanic materials

As mentioned above, most portland and other hydraulic cements produce lime during hydration (setting). It is desirable to react the lime to reduce the attack on the glass fibers. It is also known that when calcium sulfate hemihydrate is present, it reacts with tricalcium aluminate in the cement to form ettringite, which can lead to undesirable cracking of the cured product. This is commonly referred to in the art as "sulfate attack". Such reactions can be prevented by the addition of "pozzolanic" materials, which are defined in ASTM C618-97 as "… … siliceous or siliceous and aluminous materials, which possess little or no cementitious value by themselves, but which in finely divided form and in the presence of moisture will chemically react with calcium hydroxide at ambient temperature to form compounds possessing cementitious properties. "one commonly used pozzolanic material is silica fume, a finely divided amorphous silica that is the product of silicon metal and ferrosilicon. Characteristically, it has a high silica content and a low aluminum content. Various natural and man-made materials have been described as having pozzolanic properties, including pumice, perlite, diatomaceous earth, tuff, volcanic earth, metakaolin, microsilica, granulated blast furnace slag and fly ash. While silica fume is a particularly convenient pozzolan for use in the panels of the present invention, other pozzolanic materials can be used. Unlike silica fume, metakaolin, granulated blast furnace slag and pulverised fly ash have a much lower silica content and a high amount of aluminium, but can be an effective pozzolanic material. When silica fume is used, it will constitute about 5 to 20 wt%, preferably 10 to 15 wt% of the reactive powders (i.e., hydraulic cement, calcium sulfate alpha hemihydrate, silica fume and lime). If other pozzolans are used instead, the amounts used will be selected to provide similar chemical properties to silica fume.

Lightweight filler/microspheres

The lightweight panels employed in the system of the present invention typically have a density of 65 to 90 pounds per cubic foot, preferably 65 to 85 pounds per cubic foot, more preferably 72 to 80 pounds per cubic foot. In contrast, a typical portland cement-based panel without wood fibers would have a density in the range of 95 to 110 pounds per cubic foot, while a portland cement-based panel with wood fibers would be about the same as SCP (about 65 to 85 pounds per cubic foot).

To assist in achieving these low densities, the panels are provided with lightweight filler particles. Such particles typically have an average diameter (average particle size) of about 10 to 500 microns. More typically, it has an average particle diameter (average particle size) from 50 to 250 microns and/or falls within a particle diameter (particle size) range of 10 to 500 microns. They also typically have a particle density (specific gravity) in the range from 0.02 to 1.00. Microspheres or other lightweight filler particles play an important role in the panels of the invention, which would otherwise be heavier than desired for building panels. As a lightweight filler, the microspheres help to reduce the average density of the product. When the microspheres are hollow, they are sometimes referred to as microspheres.

When the microspheres are hollow, they are sometimes referred to as microspheres.

The microspheres themselves are non-flammable or, if flammable, are added in a small enough amount to not render the SCP panel flammable. Typical lightweight fillers for inclusion in the mixture used to make the panels of the present invention are selected from the group consisting of ceramic microspheres, polymer microspheres, perlite, glass microspheres, and/or fly ash cenospheres (cenospheres).

Ceramic microspheres can be made from a variety of materials and using different manufacturing processes. While a variety of ceramic microspheres may be used as the filler component in the panels of the present invention, the preferred ceramic microspheres of the present invention are produced as a coal combustion byproduct and are a component of fly ash found in coal burning facilities, such as EXTENDEPHENOSPERES-SG manufactured by Kish Company Inc., Mentor, Ohio or FILLITE brand ceramic microspheres manufactured by Trelleberg Fillite Inc., Norcross, Georgia USA. The chemical composition of the preferred ceramic microspheres of the present invention is primarily Silica (SiO) in the range of about 50 to 75 weight percent₂) And alumina (Al) in the range of about 15 to 40 wt%₂O₃) And up to 35 wt% of other materials. Preferred ceramic microspheres of the invention are hollow spherical particles having a diameter in the range of 10 to 500 microns, a shell thickness of typically about 10% of the sphere diameter, and a particle density of preferably about 0.50 to 0.80 g/mL. Preferred ceramic microspheres of the invention have a crush strength greater than 1500psi (10.3MPa), and preferably greater than 2500psi (17.2 MPa).

The preference for ceramic microspheres in the panels of the invention stems primarily from the fact that: which is about 3 to 10 times stronger than most synthetic glass microspheres. In addition, the preferred ceramic microspheres of the present invention are thermally stable and provide enhanced dimensional stability to the panels of the present invention. Ceramic microspheres can be used in a range of other applications such as adhesives, sealants, caulks, roofing compounds, PVC shear wall materials, coatings, industrial coatings and high temperature resistant plastic composites. While they are preferred, it should be understood that it is not necessary that the microspheres be hollow and spherical, as it is the particle density and compressive strength that provide the panel of the present invention with low weight and important physical properties. Alternatively, porous irregular particles may be used instead, as long as the resulting panel meets the desired properties.

The polymeric microspheres (if present) are typically hollow spheres, the shell of which is made of a polymeric material, such as polyacrylonitrile, polymethacrylonitrile, polyvinyl chloride or polyvinylidene chloride, or mixtures thereof. The shell may enclose a gas used to expand the polymer shell during manufacture. The outer surfaces of the polymer microspheres may have some type of inert coating such as calcium carbonate, titanium oxide, mica, silica and talc. The polymeric microspheres have a particle density of preferably about 0.02 to 0.15g/mL and have a diameter in the range of 10 to 350 microns. The presence of polymeric microspheres may facilitate both low panel density and enhanced cutability and nailability.

Other lightweight fillers (e.g., glass microspheres, perlite or hollow aluminosilicate cenospheres or microspheres derived from fly ash) are also suitable for inclusion in the mixture in combination with or in place of the ceramic microspheres used to make the panels of the present invention.

Glass microspheres are typically made of alkali resistant glass materials and may be hollow. Typical glass microspheres are commercially available from GYPTEK inc, Suite 135, 16Midlake Blvd SE, Calgary, AB, T2X 2X7, CANADA.

In a first embodiment of the invention, only ceramic microspheres are used throughout the thickness of the panel. The face sheet typically contains about 35 to 42 wt% ceramic microspheres, which are uniformly distributed throughout the thickness of the face sheet.

In a second embodiment of the invention, a blend of lightweight ceramic and glass microspheres is used throughout the thickness of the panel. The volume fraction of glass microspheres in the panel of the second embodiment of the invention will typically be in the range of 0 to 15% of the total volume of the dry ingredients, wherein the dry ingredients of the composition are reactive powders (examples of reactive powders: hydraulic cement alone; a blend of hydraulic cement and pozzolan; or a blend of hydraulic cement, calcium sulphate alpha hemihydrate, pozzolan and lime), ceramic microspheres, polymer microspheres and alkali-resistant glass fibres. Typical aqueous mixtures have a ratio of water to reactive powder of from greater than 0.3/1 to 0.7/1.

If desired, the panel may have a single layer, as shown in FIG. 3. However, panels are typically made by a process of applying multiple layers, which may or may not leave distinct layers in the final panel product, depending on how the layers are applied and cured and whether the layers are of the same or different compositions.

FIG. 5 shows a multi-layer structure of a panel 31 having layers 33, 35, 37 and 39. In the multilayer structure, the compositions of the layers may be the same or different. Typical thicknesses of the layers are in the range of about 1/32 to 1.0 inch (about 0.75 to 25.4 mm). Where only one outer layer is used, it will typically be less than 3/8 of the total panel thickness.

FIGS. 5A through 5C illustrate a typical design and size of a tongue and groove employed in an 3/4 inch (19.1mm) thick SCP panel 4.

FIG. 6 is a side elevational view of the single layer SCP panel 4 of FIG. 1 supported on the metal frame 6 of FIG. 2in the system of the present invention. For purposes of illustration, the fastener 32 is schematically shown as attaching the SCP panel 4 to the frame 6. In practice, the SCP panel 4 may be mechanically or adhesively attached to the frame 6. Fig. 7 is a perspective view of a metal stud wall 5 with a respective SCP panel 4 attached to opposite sides.

SCP panel formulation

The components used to make the shear resistant panels of the present invention are hydraulic cement, calcium sulfate alpha hemihydrate, active pozzolan (e.g., silica fume), lime, ceramic microspheres, alkali-resistant glass fibers, superplasticizers (e.g., sodium salt of polynaphthalene sulfate), and water. Typically, both hydraulic cement and calcium sulfate alpha hemihydrate are present. If calcium sulfate alpha hemihydrate is not present with the silica fume, the long-term durability of the composition is compromised. When no portland cement is present, water/moisture durability is compromised. Small amounts of accelerators and/or retarders may be added to the composition to control the setting characteristics of the green (i.e., uncured) material. Typical non-limiting additives include accelerators for hydraulic cements (e.g., calcium chloride), accelerators for calcium sulfate alpha hemihydrate (e.g., gypsum), retarders (e.g., DTPA (diethylenetriaminepentaacetic acid), tartaric acid or alkali metal salts of tartaric acid (e.g., potassium tartrate)), shrinkage reducing agents (e.g., ethylene glycol), and entrained air.

The panels of the present invention will include a continuous phase in which alkali-resistant glass fibers and lightweight fillers (e.g., microspheres) are uniformly distributed. The continuous phase is produced by curing an aqueous mixture of reactive powders, i.e., a blend of hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan and lime, preferably including a superplasticizer and/or other additives.

Typical weight ratios, based on the dry weight of the reactive powder, such as hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan and lime, of examples of reactive powders (inorganic binders) of the present invention are shown in table 1. Table 1A lists typical ranges for reactive powders, lightweight fillers and glass fibers in the compositions of the present invention.

Lime is not required in all formulations of the invention, but it has been found that the addition of lime provides good panels and it will typically be added in amounts greater than about 0.2 wt%. Thus, in most cases, the amount of lime in the reactive powder will be about 0.2 to 3.5 wt%.

In a first embodiment of the invention, the dry components of the composition will be reactive powders (i.e., a blend of hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan, and lime), ceramic microspheres, and alkali-resistant glass fibers, and the wet components of the composition will be water and a superplasticizer. The dry ingredients and the wet ingredients are combined to produce the panels of the present invention. The ceramic microspheres are uniformly distributed in the matrix throughout the entire thickness of the panel. The inventive panel is formed from about 49 to 56 wt% reactive powder, 35 to 42 wt% ceramic microspheres, and 7 to 12 wt% alkali resistant glass fibers, based on the total weight of the dry ingredients. In a broad range, the inventive panel is formed from 35 to 58 wt% reactive powder, 34 to 49 wt% lightweight filler (e.g., ceramic microspheres), and 6 to 17 wt% alkali resistant glass fibers of the total dry ingredients. The amount of water and superplasticizer added to the dry ingredients will be sufficient to provide the desired slurry fluidity needed to meet the processing considerations of any particular manufacturing process. Typical addition rates of water are in the range of 35 to 60% by weight of the reactive powder and typical addition rates of superplasticizers are in the range of 1 to 8% by weight of the reactive powder.

The glass fibers are monofilaments having a diameter of about 5 to 25 microns, preferably about 10 to 15 microns. Monofilaments are typically combined into strands of 100 filaments that can be bundled into rovings having about 50 strands. The length of the glass fibers will typically be about 0.25 to 1 or 2 inches (6.3 to 25 or 50mm) or about 1 to 2 inches (25 to 50mm), and broadly about 0.25 to 3 inches (6.3 to 76 mm). The fibers have a random orientation, providing isotropic mechanical behavior in the plane of the panel.

A second embodiment of the invention contains a blend of ceramic and glass microspheres that are uniformly distributed throughout the thickness of the panel. Thus, in a second embodiment of the invention, the dry components of the composition will be reactive powders (hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan and lime), ceramic microspheres, glass microspheres and alkali-resistant glass fibers, and the wet components of the composition will be water and superplasticizer. The dry ingredients and the wet ingredients will be combined to produce the panels of the present invention. The volume fraction of glass microspheres in the panel will typically be in the range of 7 to 15% of the total volume of the dry ingredients. The inventive panel is formed from about 54 to 65 wt% reactive powder, 25 to 35 wt% ceramic microspheres, 0.5 to 0.8 wt% glass microspheres, and 6 to 10 wt% alkali resistant glass fibers, based on the total weight of the dry ingredients. In a broad range, the inventive panel is formed from 42 to 68 wt% reactive powder, 23 to 43 wt% lightweight filler (e.g., ceramic microspheres), 0.2 to 1.0 wt% glass microspheres, and 5 to 15 wt% alkali resistant glass fibers, based on total dry ingredients. The amount of water and superplasticizer added to the dry ingredients will be adjusted to provide the desired slurry fluidity needed to meet the processing considerations of any particular manufacturing process. Typical addition rates of water range from 35 to 70% by weight of the reactive powder, but when it is desired to use the ratio of water to reactive powder to reduce panel density and improve cuttability, the addition rate can be higher than 60% up to 70% (the weight ratio of water to reactive powder is 0.6/1 to 0.7/1), preferably 65% to 75%. The amount of superplasticizer will be in the range of 1 to 8% by weight of the reactive powder. The glass fibers are monofilaments having a diameter of about 5 to 25 microns, preferably about 10 to 15 microns. They are typically bundled into strands and rovings, as discussed above. The length of the glass fibers is typically about 1 to 2 inches (25 to 50mm), and broadly about 0.25 to 3 inches (6.3 to 76 mm). The fibers will have random orientation providing isotropic mechanical behavior in the plane of the panel.

In a third embodiment of the present invention, a multi-layer structure in a panel is created in which the outer layer has improved nailability (fastening ability)/cuttability. This is achieved by increasing the water to cement ratio in the outer layer and/or changing the amount of filler and/or adding polymer microspheres in a small enough amount that the panel remains non-combustible. The core of the panel will typically contain ceramic microspheres or a blend of one or more of ceramic microspheres, glass microspheres and fly ash cenospheres uniformly distributed throughout the thickness of the layer.

The dry ingredients of the core layer of this embodiment of the invention will be reactive powders (typically hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan and lime), lightweight filler particles (typically microspheres, such as only one or more of ceramic microspheres or ceramic microspheres, glass microspheres and fly ash cenospheres) and alkali-resistant glass fibers, and the wet ingredients of the core layer are water and superplasticizer. The dry ingredients and the wet ingredients will be combined to produce the core layer of the panel of the present invention. The core of the panel of the present invention is preferably formed of about 49 to 56 wt% reactive powder, 35 to 42 wt% hollow ceramic microspheres and 7 to 12 wt% alkali resistant glass fibers, or about 54 to 65 wt% reactive powder, 25 to 35 wt% ceramic microspheres, 0.5 to 0.8 wt% glass microspheres or fly ash cenospheres and 6 to 10 wt% alkali resistant glass fibers, based on the total weight of the dry ingredients. In a broad range, the core layer of the panel of this embodiment of the invention is typically formed from about 35 to 58 wt% reactive powder, 34 to 49 wt% lightweight filler (e.g., ceramic microspheres), and 6 to 17 wt% alkali resistant glass fibers, or from about 42 to 68 wt% reactive powder, 23 to 43 wt% ceramic microspheres, up to 1.0 wt% and preferably 0.2 to 1.0 wt% other lightweight filler (e.g., glass microspheres or fly ash cenospheres), and 5 to 15 wt% alkali resistant glass fibers, based on the total dry ingredients. The amount of water and superplasticizer added to the dry ingredients will be adjusted to provide the desired slurry fluidity needed to meet the processing considerations of any particular manufacturing process. Typical addition rates of water will be in the range between 35 and 70% by weight of the reactive powder, but when it is desired to use the ratio of water to reactive powder to reduce panel density and improve nailability, the addition rate will be greater than 60% up to 70% and typical addition rates of superplasticizers will be in the range between 1 and 8% by weight of the reactive powder. When the ratio of water to reactive powder is adjusted, the slurry composition will be adjusted to provide the panel of the present invention with the desired properties.

Polymeric microspheres and polymeric fibers are generally absent, which would render the SCP panel flammable.

The dry ingredients of the outer layer of this embodiment of the invention will be reactive powders (typically hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan and lime), lightweight filler particles (typically microspheres, such as only one or more of ceramic microspheres, glass microspheres and fly ash cenospheres) and alkali-resistant glass fibers, and the wet ingredients of the outer layer will be water and superplasticizer. The dry ingredients and the wet ingredients are combined to produce the outer layer of the panel of the present invention. In the outer layer of the panel of this embodiment of the invention, the amount of water is selected to give the panel good fastening and cutting ability. The outer layer of the panel of the present invention is preferably formed of about 54 to 65 wt% reactive powder, 25 to 35 wt% ceramic microspheres, 0 to 0.8 wt% glass microspheres, and 6 to 10 wt% alkali resistant glass fibers, based on the total weight of the dry ingredients. In a broad range, the outer layer of the panel of the present invention is formed from about 42 to 68 wt% reactive powder, 23 to 43 wt% ceramic microspheres, up to 1.0 wt% glass microspheres (and/or fly ash cenospheres), and 5 to 15 wt% alkali resistant glass fibers, based on the total dry composition. The amount of water and superplasticizer added to the dry ingredients will be adjusted to provide the desired slurry fluidity needed to meet the processing considerations of any particular manufacturing process. Typical addition rates of water are in the range between 35 and 70% by weight of the reactive powder, and in particular greater than 60% up to 70% when the ratio of water to reactive powder is adjusted to reduce panel density and improve nailability, and typical addition rates of superplasticizers will be in the range between 1 and 8% by weight of the reactive powder. The preferred thickness of the outer layer is in the range of between 1/32 to 4/32 inches (0.8 to 3.2mm), and the thickness of the outer layer will be less than 3/8 of the total thickness of the panel when only one outer layer is used.

In both the core and outer layers of this embodiment of the invention, the glass fibers are monofilaments having a diameter of about 5 to 25 microns, preferably 10 to 15 microns. The monofilaments are typically bundled into strands and rovings, as discussed above. The length is typically about 1 to 2 inches (25 to 50mm), and broadly about 0.25 to 3 inches (6.3 to 76 mm). The orientation of the fibres will be random, providing an isotropic mechanical behaviour in the plane of the panel.

The invention also includes a fourth embodiment of a multi-layer panel having a density of 65 to 90 pounds per cubic foot and being capable of resisting shear loads when fastened to a frame, and comprising: a core layer having a continuous phase resulting from curing of an aqueous mixture, the continuous phase resulting from curing of an aqueous mixture comprising (on a dry basis) 35 to 70 wt.% of a reactive powder, 20 to 50 wt.% of a lightweight filler, and 5 to 20 wt.% of glass fibers, the continuous phase being reinforced with glass fibers and containing lightweight filler particles having a particle specific gravity of from 0.02 to 1.00 and an average particle size of about 10 to 500 microns; and at least one outer layer on each opposing side of the inner layer having a respective other continuous phase resulting from an aqueous mixture comprising cured (on a dry basis) 35 to 70 wt.% reactive powder, 20 to 50 wt.% lightweight filler, and 5 to 20 wt.% glass fibers, the continuous phase being reinforced with glass fibers and containing lightweight filler particles having a particle specific gravity of from 0.02 to 1.00 and an average particle size of about 10 to 500 microns, wherein the at least one outer layer has a higher percentage of glass fibers than the inner layer. For the example in fig. 5, layer 35 may be an inner layer and layers 33, 37, 39 may be outer layers having a higher percentage of glass fibers than the inner layer.

Making the Panel of the invention

The reactive powders (e.g., a blend of hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan, and lime) and lightweight fillers (e.g., microspheres) are blended in a dry state in a suitable mixer.

Next, water, a superplasticizer (e.g., sodium salt of polynaphthalene sulfate), and a pozzolan (e.g., silica fume or metakaolin) are mixed in another mixer for 1 to 5 minutes. If desired, a retarder (e.g., potassium tartrate) is added at this stage to control the coagulation characteristics of the slurry. Dry ingredients are added to the mixer containing the moist ingredients and mixing is continued for 2 to 10 minutes to form a smooth homogenous slurry.

The slurry is then combined with the glass fibers in any of several ways with the goal of obtaining a uniform slurry mixture. The cementitious panel is then formed by pouring the fiber-containing slurry into an appropriate mold having the desired shape and size. If necessary, vibration is provided to the mould to obtain good compaction of the material in the mould. Appropriate smoothing strips or spatulas are used to give the panels the desired surface finish characteristics.

One of the various methods used to make multi-layer SCP panels is as follows. The reactive powders (e.g., a blend of hydraulic cement, calcium sulfate alpha hemihydrate, pozzolan, and lime) and lightweight fillers (e.g., microspheres) are blended in a dry state in a suitable mixer. Next, water, a superplasticizer (e.g., sodium salt of polynaphthalene sulfate), and a pozzolan (e.g., silica fume or metakaolin) are mixed in another mixer for 1 to 5 minutes. If desired, a retarder (e.g., potassium tartrate) is added at this stage to control the coagulation characteristics of the slurry. Dry ingredients are added to the mixer containing the moist ingredients and mixing is continued for 2 to 10 minutes to form a smooth homogenous slurry.

The slurry can be combined with the glass fibers in several ways with the aim of obtaining a homogeneous mixture. The glass fibers will typically have the form of rovings chopped into shorter lengths. In a preferred embodiment, the slurry and chopped glass fibers are sprayed into the panel mold simultaneously. Preferably, multiple passes are made to produce a thin layer, preferably up to about 0.25 inch (6.3mm) thick, built into a uniform panel without a specific pattern and having a thickness of 1/4 to 1 inch (6.3 to 25.4 mm). For example, in one application, a 3 x 5 foot (0.91 x 1.52m) panel may be made by six passes of spraying in the length and width directions. When depositing each layer, a roller may be used to ensure that the slurry and glass fibers are in homogeneous contact. The layer may be flattened after the rolling step with a flattening strip or other suitable means. Typically, compressed air will be used to atomize the slurry. As the slurry exits the spray nozzle, it mixes with the glass fibers cut from the roving by the chopper mechanism mounted on the spray gun. A homogeneous mixture of slurry and glass fibers is deposited in the panel mold as described above.

If desired, the outer surface layer of the panel may contain polymer spheres or be otherwise configured so that fasteners used to attach the panel to the frame may be easily driven. The preferred thickness of such layers will be about 1/32 inches to 4/32 inches (0.8 to 3.2 mm). The same procedure described above for making the panel core can be used to apply the outer layer of the panel.

Other methods for depositing the mixture of slurry and glass fibers will occur to those skilled in the art of panel making. For example, rather than using a mass production process to make each panel, a continuous sheet can be prepared in a similar manner that can be cut into panels of the desired dimensions after the material has set sufficiently. The percentage of fiber relative to the volume of the slurry is typically approximately in the range of 0.5% to 3%, for example 1.5%. Typical panels have a thickness of about 1/4 to 1-1/2 inches (6.3 to 38.1 mm).

Another method for making the panels of the present invention is by using the process disclosed in U.S. patent application No. 10/666,294, which is incorporated herein by reference. United states patent application No. 10/666,294, incorporated herein by reference, discloses depositing fibers on a slurry layer after the process of initially depositing a loosely distributed and chopped fiber or slurry layer on a moving web. The embedment device compacts the newly deposited fibers into the slurry, after which an additional layer of slurry and then chopped fibers are added, followed by embedment again. The process is repeated for each layer of the panel as needed. Upon completion, the board has a more evenly distributed fiber component, which results in a relatively strong panel without the need to have a thick mat of reinforcing fibers, as taught in the prior art production techniques for cementitious panels.

More specifically, U.S. patent application No. 10/666,294 discloses a multi-layer process for producing structural cementitious panels, comprising: (a.) providing a mobile network; (b.) depositing a first layer of loose fibers over the web or (c.) depositing a layer of settable slurry; (d.) depositing a second loose fiber layer on the slurry; (e.) embedding the second fibrous layer into a slurry; and (f.) repeating the slurry deposition of steps (c.) through (d.) until a desired number of layers of settable fiber reinforcing slurry are obtained in the panel.

Fig. 21 is a diagrammatic elevation view of an apparatus suitable for carrying out the process of U.S. patent application No. 10/666,294. Referring now to FIG. 21, a structural panel production line is diagrammatically shown and generally designated 310. The production line 310 includes a support frame or forming table 312 having a plurality of feet 313 or other supports. On the support frame 312 is included a moving carrier 314, such as an endless rubber-like conveyor belt having a smooth and water-impermeable surface (although porous surfaces are contemplated). As is well known in the art, the support frame 312 may be made of at least one table-like segment, which may include designated feet 313. The support frame 312 also includes a main drive roller 316 at a distal end 318 of the frame and an idler roller 320 at a proximal end 322 of the frame. Also, at least one belt tracking and/or tensioning device 324 is preferably provided for maintaining a desired tension and positioning of the carrier 314 on the rollers 316, 320.

Also, in a preferred embodiment, a web 326 of kraft paper, release paper and/or other support material (as is well known in the art) designed to support the slurry before it sets may be provided and laid on the carrier 314 to protect it and/or keep it clean. However, it is also contemplated that the panels produced by the present line 310 are formed directly on the carrier 314. In the latter case, at least one tape rinsing unit 328 is provided. The carrier 314 is moved along the support frame 312 by a combination of motors, pulleys, belts or chains, which drive a main drive roller 316 as is known in the art. It is contemplated that the speed of the carrier 314 may be varied to suit the application.

In the apparatus of fig. 21, structural cement panel production is initiated by the process of depositing a layer of loose and chopped fibers 330 or slurry on a mesh 326. An advantage of depositing the fibers 330 prior to the deposition of the first slurry is that the fibers will be embedded near the outer surface of the resulting panel. The present production line 310 contemplates a variety of fiber deposition and chopping devices, however, the preferred system employs at least one gantry 331 that holds several spools 332 of fiberglass rope from each of which spools 332 fiber rope 334 is fed to a chopping station or apparatus (also referred to as a chopper 336).

The chopper 336 includes a rotating bladed roll 338 from which extend radially extending blades 340 extending transversely across the width of the carrier 314, and the rotating bladed roll 338 is disposed in close, contacting and rotating relationship with a support roll 342. In a preferred embodiment, the vaned roller 338 and the anvil roller 342 are disposed in a relatively close relationship such that rotation of the vaned roller 338 also rotates the anvil roller 342, however, the reverse is also contemplated. Also, the anvil roller 342 is preferably covered with a resilient support material against which the blades 340 chop the cords 334 into segments. The spacing of the blades 340 on the rollers 338 determines the length of the chopped fibers. As seen in fig. 21, a chopper 336 is disposed on the carrier 314 near the proximal end 322 to maximize productive use of the length of the production line 310. When the fiber cords 334 are chopped, the fibers 330 fall loosely onto the carrier web 326.

Next, a slurry feed station or slurry feeder 344 receives a supply of slurry 346 from a remote mixing location 347 (e.g., a funnel, tank, etc.). It is also contemplated that the process may begin with the initial deposition of the slurry on the carrier 314. The slurry is preferably comprised of variable amounts of portland cement, gypsum, aggregate, water, accelerators, plasticizers, foaming agents, fillers and/or other ingredients and has been described above and in the patents listed above for the production of SCP panels, which are incorporated herein by reference. The relative amounts of these ingredients (including the removal of some of the ingredients described above or the addition of other ingredients) may be varied to suit the application.

While various configurations of slurry feeders 344 are contemplated for uniformly depositing a thin layer of slurry 346 on the moving carrier 314, preferred slurry feeders 344 include a main metering roll 348 disposed transversely to the direction of travel of the carrier 314. Companion or backup roll 350 is disposed in close parallel and rotational relationship to metering roll 348 to form nip 352 therebetween. A pair of sidewalls 354 (preferably made of a non-stick material such as Teflon brand material or the like) prevent the slurry 346 poured into the nip 352 from spilling out of the sides of the feeder 344.

The feeder 344 deposits a uniform and relatively thin layer of slurry 346 on the moving carrier 314 or carrier web 326. Suitable layer thicknesses range from about 0.05 inch to 0.20 inch. However, with the preferred four layers in the preferred structural panel produced by the present process and a suitable build panel of approximately 0.5 inches, a particularly preferred slurry layer thickness is approximately 0.125 inches.

Referring now to fig. 21 and 22, to achieve the slurry layer thickness as described above, several features are provided to the slurry feeder 344. First, to ensure uniform deposition of the slurry 346 throughout the web 326, the slurry is delivered to the feeder 344 by a hose 356, the hose 356 being located in a laterally reciprocating, cable driven and fluid energized dispenser 358, the dispenser 358 being of a type well known in the art. Slurry flowing from hose 356 is thus poured into feeder 344 in a lateral reciprocating motion to fill reservoir 359 defined by rollers 348, 350 and sidewalls 354. Rotation of the metering roll 348 thus draws a layer of slurry 346 from the holding tank.

Next, a thickness monitoring or thickness control roll 360 is positioned slightly above and/or slightly upstream of the vertical centerline of the main metering roll 348 to adjust the thickness of the slurry 346 drawn from the feeder reservoir 357 on the outer surface 362 of the main metering roll 348. Also, the thickness control roll 360 allows for handling slurries having different and varying viscosities. The main metering roll 348 is driven in the same direction of travel "T" as the direction of movement of the carrier 314 and carrier web 326, and the main metering roll 348, backup roll 350 and thickness monitoring roll 360 are all rotatably driven in the same direction, which minimizes the chance of premature setting of the slurry on the respective moving outer surfaces. As the slurry 346 on the outer surface 362 moves toward the carrier web 326, a transverse release line 364 located between the main metering roll 348 and the carrier web 326 ensures that the slurry 346 is fully deposited on the carrier web and does not back up toward the nip 352 and the feeder reservoir 359. The stripping line 364 also helps to keep the main metering roll 348 free of prematurely setting slurry and maintains a relatively uniform curtain of slurry.

A second chopper station or apparatus 366 (preferably the same as chopper 336) is positioned upstream of feeder 344 to position a second layer of fibers 368 on slurry 346. In a preferred embodiment, the shredder device 366 is fed with the cords 334 from the same gantry 331 that feeds the shredder 336. However, it is contemplated that a separate rack 331 may be supplied to each individual shredder, depending on the application.

Referring now to fig. 21 and 23, next an embedment device, generally designated 370, is disposed in operative relationship with the slurry 346 and the moving carrier 314 of the production line 310 for embedding the fibers 368 into the slurry 346. Although a variety of embedment devices are contemplated, including but not limited to vibrators, sheep's feet rollers, and the like, in a preferred embodiment, embedment device 370 includes at least a pair of generally parallel shafts 372 mounted transversely to the direction of travel "T" of carrier web 326 on frame 312. Each shaft 372 is provided with a plurality of relatively large diameter disks 374, the disks 374 being axially separated from one another on the shaft by smaller diameter disks 376.

During SCP panel production, the shaft 372 and the disks 374, 376 rotate together about the longitudinal axis of the shaft. Either or both of the shafts 372 may be powered, as is well known in the art, and if only one shaft is powered, the other shaft may be driven by a belt, chain, gear drive, or other known power transmission technique to maintain a direction and speed corresponding to the drive rollers. The respective disks 374, 376 of adjacent and preferably parallel shafts 372 are interdigitated with one another to create a "kneading" or "massaging" action in the slurry that embeds the fibers 368 previously deposited on the slurry. In addition, the close, interdigitated and rotating relationship of the disks 372, 374 prevents the accumulation of slurry 346 on the disks and, in effect, creates a "self-cleaning" action, which significantly reduces line downtime due to premature setting of slurry clumps.

The interdigitating relationship of the disks 374, 376 on the shaft 372 includes the close proximity disposition of the opposing peripheries of the smaller diameter spacer disks 376 and the relatively larger diameter main disks 374, which also facilitates a self-cleaning action. When the disks 374, 376 are rotated relative to each other in close proximity (but preferably in the same direction), it is difficult for the slurry particles to be blocked and prematurely set by the apparatus. By providing two sets of disks 374 that are laterally offset with respect to each other, the slurry 346 is subjected to multiple splitting actions, thereby creating a "kneading" action that further embeds the fibers 368 in the slurry 346.

Once the fibers 368 are embedded, or in other words, as the moving carrier web 326 passes through the embedding means 370, the first layer 377 of the SCP panel is completed. In a preferred embodiment, the height or thickness of the first layer 377 is in the approximate range of 0.05-0.20 inches. This range has been found to provide the required strength and rigidity when combined with similar layers in an SCP panel. However, other thicknesses are contemplated depending on the application.

In order to build a structural cementitious panel with the required thickness, additional layers are required. To this end, a second slurry feeder 378 (which is substantially identical to feeder 344) is provided in operative relationship with the moving carrier 314 and is configured to deposit an additional layer 380 of slurry 346 on the existing layer 377.

Next, additional choppers 382 (which are substantially identical to choppers 336 and 366) are provided in operative relationship with frame 312 to deposit a third layer of fibers 384 provided from a stand (not shown) that is constructed and arranged in a similar fashion as stand 331 with respect to frame 312. Fibers 384 are deposited on slurry layer 380 and embedded using second embedment device 386. Similar in construction and arrangement to embedment device 370, second embedment device 386 is mounted slightly higher relative to the moving carrier web 314 so that the first layer 377 is undisturbed. In this way, a second layer 380 of slurry and embedded fibers is created.

Referring now to fig. 21, for each successive layer of settable slurry and fibers, additional slurry feeder stations 344, 378, 402 followed by fiber choppers 336, 366, 382, 404 and embedment devices 370, 386, 406 are provided on the production line 310. In a preferred embodiment, four overall layers (see, e.g., panel 101 of FIG. 29) are provided to form an SCP panel. After providing the four layers of fiber embedded settable slurry (as described above), the frame 312 is preferably provided with a forming device 394 to shape the upper surface 396 of the panel. Such forming devices 394 are known in the art of settable slurry/board production and are typically spring loaded or vibrating plates that conform to the height and shape of the multi-layer panel to suit the desired dimensional characteristics.

The panel produced has a plurality of layers (see, for example, layers 22, 24, 26, 28 of panel 31 of fig. 5) which, after coagulation, form an integral fiber reinforced block. As long as the presence and placement of fibers in each layer is controlled by and maintained within certain desired parameters (as disclosed and described below), it will not be practically possible to delaminate the panel.

At this point, the slurry layer has begun to set and the individual panels are separated from each other by a cutting device 398, which in the preferred embodiment is a water jet cutter. Other cutting devices, including moving blades, are considered suitable for this operation, as long as they can produce suitably sharp edges in the present panel composition. The cutting device 398 is arranged relative to the production line 310 and the frame 312 so that panels of a desired length are produced, which may differ from the representation shown in fig. 21. Because of the relatively low speed of the carrier web 314, the cutting device 398 may be mounted to cut perpendicular to the direction of travel of the web 314. For faster production speeds, such cutting devices are known to be mounted to the production line 310 at an angle to the direction of web travel. After cutting, the separated panels 321 are stacked for further processing, packaging, storage, and/or shipping, as is known in the art.

In terms of quantity, the influence of the number of fibres and pulp layers, the volume fraction of fibres in the panel and the thickness of each pulp layer, and the fibre strand diameter on the efficiency of fibre embedment has been studied. In the analysis, the following parameters were identified:

v_Ttotal volume of the composition

v_sTotal panel slurry volume

v_fTotal panel fiber volume

v_f，1Total fiber volume/layer

v_T，1Total composition volume/layer

v_s，1Total slurry volume/layer

N₁Total number of slurry layers; total number of fibrous layers

V_fTotal panel fiber volume fraction

d_fEquivalent diameter of individual fiber strands

l_fLength of individual fibre strand

t is the panel thickness

t₁Total thickness of individual layers comprising slurry and fibers

t_s，1Thickness of individual slurry layer

n_f，1，n_f1，1，n_f2，1Total number of fibres in the fibre layer

Projected fiber surface area fractionS_f1，1 ^p

The panel is assumed to be composed of an equal number of slurry and fiber layers. Making the number of these layers equal to N₁And the fiber volume fraction in the panel is equal to V_f。

In sum, the projected fiber surface area fraction S imparted to a fibrous web layer deposited on a distinct slurry layer^p _f，1The following mathematical relationship:

wherein, V_fIs total panel fiber volume fraction, t is total panel thickness, d_fIs the diameter of the fiber strand, N₁Is the total number of fibrous layers, and t_s，1Is the thickness of the layer of the different slurry used.

Thus, to achieve good fiber embedment efficiency, the objective function is to keep the fiber surface area fraction below a certain critical value. Notably, by varying one or more variables appearing in equations 8 and 10, the projected fiber surface area fraction can be tailored to achieve good fiber embedment efficiency.

Different variables that affect the projected fiber surface integral number value have been identified, and various methods have been proposed to tailor the magnitude of the "projected fiber surface fraction" to achieve good fiber embedment efficiency. These methods involve varying one or more of the following variables to maintain the projected fiber surface area fraction below a critical threshold: the number of distinct fiber and slurry layers, the thickness of the distinct slurry layers, and the diameter of the fiber strand.

Based on this basic work, it has been found that the projected fiber surface area fraction S_f1，1 ^pPreferred magnitudes of (d) are as follows:

preferred projected fiber surface area fraction

Most preferably the projected fiber surface area fraction

For design panel fiber volume fraction V_fRealization of the aforementioned preferred magnitudes of projected fiber surface area fractions may be possible by tailoring one or more of the following variables — the total number of distinct fiber layers, the thickness of the distinct slurry layers, and the fiber strand diameter. Specifically, the ideal ranges for these variables that result in preferred magnitudes for the projected fiber surface area fraction are as follows:

thickness of dissimilar slurry layers in a multilayer SCP panelt_s，1

Preferred thickness t of the distinct slurry layers_s，1Less than or equal to 0.20 inch

More preferred thickness t of the distinct slurry layer_s，1Less than or equal to 0.12 inch

Most preferred thickness t of the distinct slurry layers_s，1Less than or equal to 0.08 inch

Number of dissimilar fiber layers in a multilayer SCP panelN₁

Preferred number N of distinct fibrous layers₁≥4

Most preferred number N of distinct fibrous layers₁≥6

Fiber strand diameterd_f

Preferred fiber strand diameter d_fNot less than 30 te

Most preferred fiber strand diameter d_fNot less than 70 special

Properties of

The SCP panel metal frame system of the present invention preferably has one or more of the properties listed in tables 2A-2D. The properties are for an 1/2 inch (12.7mm) thick SCP panel unless otherwise indicated.

The horizontal design shear capacity in table 2D provides a safety factor of 3.

Systems having 3/8-3/4 inch (9-19mm) (e.g., 1/2 inch (12.5mm)) thick SCP panels to mechanically and/or adhesively laterally support a metal frame typically have a nominal wall shear capacity (also referred to as nominal peel shear strength) of 200 to 1200 or 400 to 1200 or 800 to 1200 pounds per linear foot when tested according to ASTM E-72.

A typical 3/4 inch (19mm) thick panel has a final load capacity of greater than 550lb (250kg) under static loading, a final load capacity of greater than 400lb (182kg) under impact loading, and a deflection of less than 0.078 inch (1.98mm) under static and impact loading with a 200lb (90.9kg) load when tested over a center 16 inch (406.4mm) span according to ASTM E661 and APA S-1 test methods.

Typically, the dry density is 65lb/ft³(1041kg/m³) To 90lb/ft³(1442kg/m³) Or 65lb/ft³(1041kg/m³) To 95lb/ft³(1522kg/m³) The panel of (a) has a flexural strength of at least 1000psi (7MPa), for example 1300psi (9MPa), preferably 1650psi (11.4MPa), more preferably at least 1700psi (11.7MPa), after soaking in water for 48 hours, as measured by the ASTM C947 test.

Generally, SCP shear wall diaphragm systems have a higher unit stiffness than shear wall systems of load-bearing masonry walls.

Typically, the vertical shear diaphragm load carrying capacity of the system will not be reduced by more than 25%, preferably not more than 20%, upon exposure to water for 24 hours in a test in which a 2 inch head of water is maintained over horizontally oriented 1/2 to 3/4 inch thick SCP panels fastened on a 10 foot by 20 foot metal frame, and then redirected in the vertical direction and tested for vertical shear diaphragm load carrying capacity.

Typically, the system will not absorb more than 0.7 pounds per square foot of water when exposed to water for 24 hours in a test in which a 2 foot head of water is maintained over an 3/4 inch thick SCP panel fastened on a 10 foot by 20 foot metal frame.

Typically, embodiments of the present system having a 10 foot wide by 20 foot long by 3/4 inch thick SCP panel diaphragm attached to a 10 foot by 20 foot metal frame do not increase by more than 5% when exposed to a 2 inch head of water maintained over an SCP panel fastened to the metal frame for 24 hours.

Typically, each component of the present system meets ASTM G-21 testing (where the system achieves a rating of approximately 1), and meets ASTM D-3273 testing (where the system achieves a rating of approximately 10). Moreover, the present system typically supports substantially zero bacterial growth when clean. Moreover, the present system is generally not edible by termites.

Because of its light weight and robustness, this combination of the present shear wall system of horizontal partitions of 1/2 to 3/4 inch thick SCP panels on a metal frame allows for the efficient use of building volume for a given building footprint to allow for the maximization of the building volume for that given building footprint. The lightweight nature of this system avoids the deadload associated with load bearing masonry systems. Less dead load allows construction of structures of comparable size on less stable soils. Further, the system may be non-directional in that the panels of the system may be placed with their long dimension parallel or perpendicular to the metal uprights of the frame without loss of strength or load bearing characteristics, wherein the ability of the system to support both dead and live loads without breakage is the same regardless of the orientation of the SCP panels on the metal frame.

The non-combustible shear wall system of the present invention may be made by a method that includes placing an SCP panel on a metal stud. The SCP panel may be placed on a vertically oriented metal frame element or on a horizontally oriented frame element (which is then vertically oriented) and attached to the frame by mechanical or adhesive means. An advantage of the present system is that the SCP panels can withstand rough machining when placed on a metal frame during construction of residential and commercial buildings. For example, the present SCP panel may preferably withstand rough finishing during construction in cold weather, such as when the ambient temperature is below 32 (0 ℃) or even when the ambient temperature is below 20 (-7.5 ℃). Preferably, in a method comprising dropping the panel onto the metal frame element such that at least one end of the panel falls at least 2 feet or at least 3 feet or in the range of 3 to 6 feet (the SCP panel does not crack) and then vertically reorienting the panel and metal frame element, the SCP panel can withstand being placed horizontally on the metal frame element at ambient temperatures below 32 (0 ℃).

Examples of the invention

The comparative structural cover plates were tested for fire resistance in a small horizontal oven (SSHF). Five samples were tested as part of a 4 foot by 4 foot assembly, 1/2 inch (13mm) Structural Cement Panels (SCP), 3/4 inch (19mm) VIROC panels, 1/2 inch (13mm) NOVATECH panels, 15/32(12mm) plywood (a-C rating), and 31/64 inch (12mm) Oriented Strand Board (OSB) with the inventive composition.

Each assembly consists of a metal frame, 358, 20 gauge CR chute and ST posts spaced 24 inches apart in the center. For each of the five tests, a test material was applied to the exposed surface, and a layer of USG SHEETROCK 5/8 inch (16mm) garecode type SCX gypsum wallboard was applied to the unexposed surface. The exposed surface material is applied vertically to the stud with a seam at the mid-span of the assembly. Thermocouples were placed in the cavities on both the underside of the exposed faceplate and the unexposed surface to make a temperature comparison of the assembly. The furnace temperature was controlled to ASTM E119 time/temperature profile. The temperature measurement consisted of completing the nominal value and unexposed surface for the duration of the test. The estimated condition of the exposed surface was observed during the test. Standard ASTM E119 temperature limits for thermocouple readings are on average 250 deg.C (136 deg.C) above ambient temperature and individual 325 deg.C (183 deg.C) above ambient temperature are used as control limits.

The purpose of the test is to provide a relative comparison of the material properties of the product in the fire test. The process does not provide a fire resistance rating for the system.

The formulations of the SCP panels used in the mini horizontal oven test (examples 1 and 3) are illustrated below in table 2E.

The test results for the five samples can be found in table 3. Both the average (a) and individual (I) readings are in minutes at the point where the temperature standard limit is exceeded during each test. The SCP panels have the composition of the panels of the present invention.

Example 1

Sample structure

Dimension 48 inches (122cm) by 48-5/8 inches (124cm)

Column: 358 ST, 20 gauge spacing: center 24 inches (61cm)

A chute: 358CR, 20 gauge; a cavity: air conditioner

And (3) facing: (fireside) one layer of 1/2 inch (13mm) USG Structural Cement Panel (SCP)

(unexposed side) one layer of 5/8 inch (16mm) SHEETROCK _ FIRECODE (X type) panel

Table 4 lists the plates employed as test materials in this example. The plate was heated as shown in table 5. Observations of this heating are shown in table 6.

Duration of fire test: 70 minutes 0 seconds

And (4) terminating the test: no plate falling off

Example 2

Sample structure

Dimension 48 inches (122cm) by 48-5/8 inches (124cm)

Column: 358 ST, 20 gauge spacing: center 24 inches (61cm)

A chute: 358CR, 20 gauge; a cavity: air conditioner

And (3) facing: (fireside) one layer of 3/4 inch VIROC board

(unexposed side) one layer of 5/8 inch (16mm) SHEETROCK _ FIRECODE (X type) panel

Table 7 lists the plates employed as test materials in this example. The plate was heated as shown in table 8. Observations of this heating are shown in table 9.

Duration of fire test: 60 minutes 0 second

And (4) terminating the test: no plate falling off

Example 3

Sample structure

Dimension 48 inches (122cm) by 48-5/8 inches (124cm)

Column: 358 ST, 20 gauge spacing: center 24 inches (61cm)

A chute: 358CR, 20 gauge; a cavity: air conditioner

And (3) facing: (fireside) one layer of 1/2 inch NovaTech plate

(unexposed side) one layer of 5/8 inch (16mm) SHEETROCK _ FIRECODE (X type) panel

Table 10 lists the plates employed as test materials in this example. The plate was heated as shown in table 1. Observations of this heating are shown in table 12.

Duration of fire test: 70 minutes 0 seconds

Test termination- -plate delamination, no plate detachment

Example 4

Sample structure

Dimension 48 inches (122cm) by 48-5/8 inches (124cm)

Column: 358 ST, 20 gauge; spacing: center 24 inches (61cm)

A chute: 358CR, 20 gauge; a cavity: air conditioner

And (3) facing: (fireside) one layer 15/32 inch (12mm) plywood (A/C) panel

(unexposed side) one layer of 5/8 inch (16mm) SHEETROCK _ FIRECODE (X-shaped) panel

Table 13 lists the plates employed as test materials in this example. The plate was heated as shown in table 14. Observations of this heating are shown in table 15.

Duration of fire test: 32 minutes and 0 seconds

And (4) terminating the test: plate falling off

Example 5

Sample structure

Dimension 48 inches (122cm) by 48-5/8 inches (124cm)

Column: 358 ST, 20 gauge; spacing: center 24 inches (61cm)

A chute: 358CR, 20 gauge; a cavity: air conditioner

And (3) facing: (fire side) layer 31/64 inch Oriented Strand Board (OSB)

(unexposed side) one layer of 5/8 inch (16mm) SHEETROCK _ FIRECODE (X type) panel

Table 16 lists the plates employed as test materials in this example. The plate was heated as shown in table 17. Observations of this heating are shown in table 18.

Duration of fire test: 32 minutes and 0 seconds

And (4) terminating the test: plate falling off

Example 6

This example determines the horizontal diaphragm strength of a single base diaphragm constructed using a prototype 3/4 inch thick SCP panel as explained below by ASTM E455-98 static load testing, single beam method for the construction of the frame base or top diaphragm construction of a building.

Test sample material

A. Substrate separator material:

prototype 3/4 "SCP-structural cement panels of the invention reinforced with fiberglass strands. The "V" groove and tongue are positioned along the 8 ' dimension of the 4 ' x 8 ' sheet. The formulations used in this example of bottom barrier tested SCP panels are listed in Table 18A.

Fastener- # 8-18X 1-5/8 "long BUGLE HEAD GRABBER SUPER DRIVE^TMScrews, spaced 6 "along the perimeter (see book of introduction), and 12" in the panel area (see book of introduction). All fasteners were placed a minimum of 3/4 inches from the panel edge and a minimum of 1/2 inches from the seam. At the panel corners, fasteners were inserted at 2 inch intervals.

Adhesive-the endermam SF polyurethane foam adhesive manufactured by Flexible Products Company of Canada, inc. One (1) 3/8 "shim was applied to the bottom of the groove before setting in place. An 3/8 "gap was left at the butt joint to allow one (1) 3/8" adhesive shim to be applied in the gap before sliding the joints together.

B.Base frame：

Fig. 8 shows a combined metal (e.g., steel) base framework. This includes the following:

A. transverse joist 150-16 gauge 10 inch deep 10 foot long Trade Ready^TMJoists, manufactured by dietrich industries. The joist was a molded Dietrich TDW5W 10IN × L10 FT 2832401316 gauge G6050 KSI.

B. Longitudinal rim rails 152-16 gauge x 10-3/16 "deep x 16' long, manufactured by Dietrich Industries, with pre-bent joist attachment locations spaced 24" (see previous citations). The track is molded Dietrich TD 16W 91/4IN × L16 FT 2832385816 GAUGE 3RD FI.

C.0.125 "thick x 2" angles 154 (fig. 10) are located on each of the spaced apart transverse end joists 156 (the joists 156 span up to 3 inches from the bearing side and from the load side corners) and are secured to the respective end transverse joists by #10-1 "drift screws at 6" spacing (see previous citations).

D. Fastening piece

# 10-16X 3/4 "long DRIVALL screw with hexagonal head for attachment to the frame.

#10-16 × 3/4 "long self-drilling screw with wafer head for attachment to the frame at 6" spacing (see previous introduction) around the outermost edge and on both sides of the butt joint.

Test specimen configuration

One (1) test specimen was constructed to have an overall dimension of 10 '-0 "x 20' -0". Fig. 8 shows a perspective view of a metal frame.

FIG. 9 shows an enlarged view of a portion of the frame of FIG. 8.

FIG. 10 shows an enlarged view of a portion AA of the frame of FIG. 8.

FIG. 11 shows a top view of a SCP panel 120 (with panel dimensions) attached to a metal frame, but the SCP panel 120 is fabricated with a tongue and groove edge (not shown) similar to FIG. 5 a.

Fig. 12, 13, 14 and 15 show enlarged views of respective portions BB, CC, DD and EE of the fig. 11 substrate.

A. At each end, the joist was attached to the rim track by using three (3) hex head #10-16 x 3/4 "long Drivall screws that entered into the sides of the joist through the pre-bent tabs and one (1) wafer head #10-16 x 3/4" long that entered into the joist through the top of the rim track from the drill screws. 0.078 "thick × 11/2" × 4 "angle 151 (which is 5" long) is also secured to each joist at 1 "(see previous citations) by 3/4" long drival screws, and one 3/4 "long drival screw is secured to the rim track.

B. A 11/2 inch by 25/8 inch by 213/4 inch KATZ pad 158 with a 2 inch long by 13/4 inch tab at each end was fastened to the joist base across the centerline of the base. The spacers 158 were attached by using 1 #10-16 x 3/4 "long Drivall screw through the end of each Katz spacer block component 158. Specifically, Katz spacer blocks 158 were positioned between the lateral joints 50 by being placed staggered on either side of the midpoint and attached by using one #10-16 × 3/4 inch long DRIVALL screw per projection.

C. On the load side, additional horizontal spacers are added to the rim rail 152 in two locations to reinforce the rim rail 152 for point loading purposes. That is, a 24 inch pad 157 for load support is provided along the longitudinal rim track between the plurality of transverse joists 150. A 20 inch long spacer 159 was secured between each lateral end joist and the respective penultimate lateral end joist generally along the longitudinal axis of the frame using four #10-16 x 3/4 inch long drival screws on each end.

D. The frame is flattened and then the prototype SCP panel is secured to the frame as shown in fig. 11. Said prototype SCP passed through a # 8-18X 1-5/8 inch long horn head GRABBER SUPER DRIVE^TMThe screws (winged self-drilling screws 162) were fastened around the perimeter at 6 "spacing (see previous citation) and inserted 2" from the corner and fastened at 12 "spacing (see previous citation) in the region. Care was taken to ensure that the fastener was held flush or slightly below the surface of the prototype SCP and also did not peel away from the steel frame. An 3/8 inch shim made of ENERFOAM SF polyurethane foam adhesive manufactured by Flexible Products Company of Canada, Inc. was applied in the joint at the butt joint and tongue and groove locations.

E. An 1/8 "x 2" angle iron is then secured to the end joist and flush with the bottom of the joist to minimize joist cracking at the bearings and present the roof member. An additional 6 inch long angle iron was fastened at the support side of the end joist and flush with the top of the joist, again to minimize chipping.

F. The test samples were left for a minimum of 36 hours to allow the adhesive to cure.

G. Fig. 16 shows a test specimen 80 made from the frame 160 of fig. 8 with the attached base 120 of fig. 9, supported by the fixture roll 70 (fig. 17) on a concrete base 98 at a central 2 foot spacing (see previous citation) around the perimeter of the specimen 80.

Fig. 17 shows an enlarged view of a portion FF of fig. 16. The support supports 74, 84 are placed at both ends of the test specimen 80. Three (3) loading cylinders 80 are positioned at opposite sides of the test specimen 80. The six (6) 18 "bearing blocks were loaded from the cylinder by a steel beam to apply load evenly to the base test specimen 80. Five (5) scale indicators were placed along the bearing side of the test specimen 80 to measure deflection. Fig. 17 shows a press 92 provided with spacers 90. A gap 96 of about 1/8 inches and a load mass 94 of 18 inches. The extrusions 92 are installed in cement 98. Another pressing member 82 is provided at the other end of the test sample 80. The extrusions 92 are supported on the solid rollers 72.

Test equipment

A. Three (3) ENERPAC model P-39 hydraulic hand pumps.

B. Three (3) ENERPAC model RC-1010 hydraulic cylinders.

C. Five scale indicators: 2 inches of travel-0.001 inch increments.

D. Three (3) omega digital meters.

E. Three (3) omega pressure sensors.

F. Three (3) 6 foot I beams.

G. Five (5) rigid supports bolted to the base.

Procedure

A. Three (3) 1-1/2 inch diameter by 10 inch stroke hydraulic cylinders were used to generate the load, one cylinder at each load point. The applied force was measured with three (3) digital meters and pressure sensors. The applied force is permanently recorded on the attached data sheet.

B. The load is generated by applying hydraulic pressure to create a mechanical force until the desired load is indicated on the digital meter.

C. The entire base assembly is loaded in 700lb increments. Each load was held for 1 minute before a deflection reading was obtained. After a 14,000lb deflection reading was obtained, the assembly was then loaded at a rate of approximately 2800 pounds per minute until failure occurred.

FIG. 19 shows a photograph of an SCP panel and metal frame substrate mounted on the test device of FIG. 16 under a design load.

FIG. 20 shows a photograph of an SCP panel and metal frame substrate mounted on the test device of FIG. 16 in a broken state.

Test results

Table 19 shows the results of the substrate separator test applying a load to the entire substrate assembly described above. The substrate has a width of 120 inches.

The following values were obtained using a safety factor of 3.0.

Final load 14,618.5lb/10.0ft 1,461.8PLF (pounds/linear foot)

Design shear 1461.8/3.0 safety factor 487.2PLF

The design shear is calculated by dividing the final load by the safety factor 3.

Table 20 shows the resulting deflection that occurs as a result of applying a load to the substrate. FIG. 18 graphically represents the data of Table 20. FIG. 18 shows experimental load versus deflection data obtained from a base diaphragm test using the base diaphragm test apparatus of FIG. 16 and using an 3/4 inch structural cement panel (SCP panel).

Table 21 shows the average supported deflection resulting from applying a load to the test sample substrate at the support point.

Based on the data obtained from this single test sample, a design shear of 487.2PLF (pounds per linear foot) can be obtained from the single substrate separator sample described above, configured as follows:

example 7

This example determines the effect of water exposure on horizontal diaphragm strength of an assembly using an 3/4 "inch thick SCP panel by ASTM E455-98 static load testing, single beam method, for a frame base or top diaphragm construction of a building.

Test sample material

A. Substrate separator material:

an 3/4 inch SCP panel reinforced with fiberglass strands. The "V" groove and tongue are positioned along the 8' dimension of the 4 foot by 8 foot blade.

The fasteners used included a #8-18 x 1-5/8 inch long horn head GRABBER SUPER DRIVE screw, which was used in GRABBER construction products, spaced 6 inches centrally along the perimeter and 12 inches centrally in the area of the panel. All fasteners were placed a minimum of 3/4 inches from the panel edge and a minimum of 1/2 inches from the seam. At the panel corners, fasteners were inserted at 2 inch intervals. The fastener location is shown in fig. 11.

B. A base framework:

the joist comprises a CSJ 16 gauge x 8 inch deep x 10 foot rim track manufactured by Dietrich Industries.

Test specimen configuration

Four (4) test specimens were constructed in overall dimensions of 10 '-0 "x 20' -0", as described above in example 6. Fig. 8 shows a perspective view of a metal frame.

However, the frame is flattened and then the prototype SCP panel is secured to the frame as shown in fig. 11. The prototype SCP was fastened around the perimeter at 6 "spacing (see previous introduction) and inserted 2" from the corner by a #8-18 x 1-5/8 "long horn head taper super drive screw (winged self drilling screw 162) fastened in the area at 12" spacing (see previous introduction). Care was taken to ensure that the fastener was held flush or slightly below the surface of the prototype SCP and also did not peel away from the steel frame. Unlike the test sample of example 6, an 3/8 inch shim made of the ENERFOAM SF polyurethane foam adhesive manufactured by Flexible Products Company of Canada, Inc. was not applied in the joint at the butt joint and tongue and groove locations.

Test equipment

A. Four (4) ENERPAC model P-39 hydraulic hand pumps.

B. Four (4) ENERPAC model RC-1010 hydraulic cylinders.

C. Five (5) scale indicators: 2 "move-0.001 increments.

D. Four (4) omega digital meters.

E. Four (4) omega pressure sensors.

F. Four (4) 6 foot I beams.

G. Six (6) rigid supports bolted to the base.

Procedure

A. Two of the test assemblies were tested under "standard as is" or dry conditions, and two samples were tested after a minimum of 24 hours of 1 "head presence.

B. Four (4) 1-1/2 "diameter hydraulic cylinders are used to generate the load, one cylinder at each load point. Four (4) calibrated digital meters and pressure sensors were used to measure the applied force. The applied force is permanently recorded on the attached data sheet.

C. The load is generated by applying hydraulic pressure to create a mechanical force until the desired load is indicated on the digital meter.

D. The entire base assembly is loaded in 700lb increments. Each load was held for 1 minute before a deflection reading was obtained. After a 14,000lb deflection reading was obtained, the assembly was then loaded at a rate of approximately 2800 pounds per minute until failure occurred.

Test results

Tables 22-38 and FIGS. 24 and 25 show the results of the substrate separator test applying a load to the entire substrate assembly described above. The substrate has a width of 120 inches. Fig. 24 shows data for dry test 1 and dry test 2. Fig. 25 shows data from wet test 1 and wet test 2.

The following values were obtained using a safety factor of 3.0.

Average final load of dried samples 15,908.2lb/10ft 1,590.8PLF

Design shear of dry sample 1,590.8PLF/3.0 safety factor 530.2PLF

Average final load for the damp samples was 14,544.5lb/10ft 1,454.4PLF

Design shear of moist sample 1,454.4PLF/3.0 safety factor 484.8PLF

These results indicate approximately 91% retention of separator strength after continuous exposure to water for a period of 24 hours.

Example 8

To determine the shear strength and shear stiffness of a substrate diaphragm assembly using a frame and SCP cover plate, tests according to the AISI TS-7-02 cantilever test method for cold-formed steel diaphragms were performed on ten (10) samples. This data may be indicative of shear performance as a shear wall.

FIG. 24 shows a substrate framework 400 used in AISI TS-7 testing.

Base separator material

Prototype 3/4 "SCP-structural cement panels reinforced with fiberglass strands. The "V" groove and tongue are positioned along the 8 ' dimension of the 4 ' x 8 ' sheet.

3/4 "plywood-23/32" GP Plus, tongue and groove (quick fit). Sturd-I-Floor specified by APA^TM1, PS1-95 liner material, sanded face, PRP-108 was exposed and manufactured by Georgia Pacific Corporation.

Fastener- # 8-18X 1-5/8 "long winged drill horn head Taper (TM) (liquid oxygen driven) screw, item number CHS8158JBW, spaced along the perimeter by 4", 6 ", and 12" (see previous introduction), and spaced in the face region by 12 "(see previous introduction). All fasteners were placed a minimum of 3/4 "from the panel edge and 1/2" from the seam. At the panel corners, fasteners were inserted at 2 "intervals.

adhesive-PL polyurethane premium construction adhesive manufactured by OSI Sealants. An 1/4 "shim was applied to all framing members, with a double shim applied at the panel butt joint. A minimum of 24 hours of cure time is provided prior to any loading.

Base frame

Joist-16 gauge x 10 "deep x 10' long Trade Ready manufactured by Dietrich Industries^TMA joist. The joists were molded Dietrrich TDJ5W 9-1/4IN × L11 FT 10-1/2IN 1445322316 gauge G6050 KSI. The average yield strength tested was 51.0 ksi.

Rim track-16 gauge x 10-3/16 "deep x 16' long, with pre-bent joist attachment locations spaced 24" (see previous citations). The track is a molded Dietrich D16W 9-1/4IN X L16 FT 1445320316 gauge G60. The average yield strength tested was 62.7 ksi. Fastener- #10-16 × 3/4 "long hex head Drivall screw.

Test specimen configuration

Ten (10) test specimens were constructed to an overall size of 11 '-11 "x 12' -0". The rim track has pre-bent projections spaced 16 "(see book, front) apart so the clip angles are welded at 24" (see book, front) intervals.

The joist was attached to the track using three (3) hex head #10-16 x 3/4 "long Drivall screws that passed through the pre-bent tabs into the sides of the joist. The S/HD15 Simpson Strong-Tie press part was fastened to the tension side of the substrate using 48 # 10X 3/4 "long hex-head self-drilling screws. A 12 gauge post 6-1/8 "× 16" long was attached to the compression joist by self-drilling screws using (14) #10 × 3/4 "long hex heads. This is added as a stiffener to avoid crushing the end joists before the diaphragm breaks. The frame is flattened and then a prototype SCP or plywood is secured to the frame. The base cover plate passes through a #8-18 multiplied by 1-5/8' long horn head taper super drive^TMThe screws were fastened around the perimeter at 4 ", 6" or 12 "spacing (see previous citations) and inserted 2" from the corner and fastened in the area at 12 "spacing (see previous citations). Care was taken to ensure that the fasteners were kept flush with or slightly below the surface of the base cover plate and also did not peel away from the steel frame. For details, please refer to drawings B6-B11. The test specimens using the adhesive were allowed to set for a minimum of 24 hours to cure the recommended adhesive.

FIG. 25 shows one of the SCP substrates 420 used in the AISI TS-7 test with an adhesive. The panel 442 is an SCP panel having a thickness of 0.670 inch to 0.705 inch. View EE shows the offset panel at the joint. View FF shows the 1/2 inch "V" shaped tongue and groove joint. View GG shows a corner. View HH shows where three SCP panels meet. View II shows a corner.

Test setup

FIG. 26 shows test equipment 450 used in AISI TS-7 testing. The test apparatus 450 has two 8 inch by 72 inch long load beams 454. The test specimen 452 was placed on a 1 inch roller 458, and a steel plate 460 was provided beneath the roller 458. Rigid supports 466 and test fixture 456 and an I-beam fixture are also provided. A hydraulic cylinder 462 applies pressure to the test specimen 452.

The test specimen is positioned in the test fixture with one of the rim tracks set flush with the top of the 10 "-30 lb/ft C-channel. The rim track is then attached to the C-shaped channel using a #12-24, T5 hex head screw at a spacing of 12 "(see previous citations). Two (2) 8 "x 72" long I-beams were then attached to the other rim track (flush with the top) using a #10 x 3/4 "long hex head self drilling screw. Fasteners were placed at 6 "intervals (see previous citation) at alternating sides of the I-beam flanges. The I-beams are also bolted together. The hydraulic cylinder is positioned on the reaction beam collinear with the I-beam.

A 1 "diameter screw was placed through the Simpson press and connected to a rigid steel clamp. A coupling nut that does not apply any specific torque to the screw. The rim tracks on the load side are positioned on two sets of rollers approximately 48 "apart. A compression member is placed on the compression side above the cover plate to prevent bulging. Two (2) 1 "diameter rollers were placed between the press tube and the steel plate on the base cover plate.

Four (4) linear sensors were placed in the following positions on the base diaphragm assembly:

# 1-is collinear with the tension joist,

# 2-collinear with the fixed rim track,

# 3-collinear with the load rim track on the buckle angle, an

# 4-collinear with the compression joist.

The linear sensor and the hydraulic pressure sensor are connected to a data acquisition system.

Test equipment

Four (4) linear sensors were placed in the following positions on the base diaphragm assembly:

one (1) ENERPAC model P-39 hydraulic hand pump.

Three (3) EnerPac model RC-1010 hydraulic cylinders.

Four (4) linear sensors.

Five (5) rigid supports bolted to the base.

One (1) C10 x 30 rigid channel bolted to three (3) of the supports.

One (1) omega digital meter.

One (1) omega pressure sensor.

Two (2) 6 foot I beams.

Procedure

The load is generated at the load point by using a hydraulic cylinder. The applied force is measured with a data acquisition device and a pressure sensor. The applied force is permanently recorded on the attached data sheet. The load is generated by applying hydraulic pressure to build up mechanical force until the desired load is indicated on the digital meter. The entire base assembly is loaded at a constant rate until no further gain in load can be obtained.

Test results

Table 37 summarizes the test results.

27-29 show load versus displacement data in pounds used to generate the values in Table 43. Specifically, FIG. 27 shows data from AISI TS-7 cantilever substrate diaphragm testing using 3/4 inch SCP panels with 4 inch-12 inch fastening schedules. FIG. 28 shows data from AIISITS-7 cantilever base diaphragm testing using 3/4 inch SCP panels with 6 inch-12 inch fastening schedule, comparable to 3/4 inch plywood. FIG. 29 shows data from AISI TS-7 cantilever substrate diaphragm testing using an 3/4 foot SCP panel with adhesive.

Tables 38-47 show the data of FIGS. 24, 25, and 26 in tabular form for test LP 804-3-0.001 inch increments.

While particular embodiments of the system employing horizontal baffles on a metal frame with structural cement panels reinforced with fibers have been shown and described, it will be apparent to those skilled in the art that various changes and modifications may be made herein without departing from the invention in its broader aspects and as set forth in the following claims.

Claims (41)

1. A non-combustible shear wall system for construction, comprising:

a vertical shear diaphragm supported on a lightweight cold-rolled metal frame, the vertical shear diaphragm comprising a reinforced, lightweight, dimensionally stable cement panel, and the frame comprising metal posts;

the panel has a density of 65 to 90 pounds per cubic foot and is capable of resisting shear loads when fastened to a frame, and comprises a continuous phase resulting from curing an aqueous mixture comprising (on a dry basis) 35 to 70 weight percent reactive powder, 20 to 50 weight percent lightweight filler, and 5 to 20 weight percent glass fiber, the continuous phase being reinforced with glass fiber and containing the lightweight filler particles having a particle specific gravity of from 0.02 to 1.00 and an average particle size of about 10 to 500 microns.

2. The system of claim 1, wherein the continuous phase results from curing an aqueous mixture of reactive powders comprising (on a dry basis) 35 to 75 weight percent calcium sulfate alpha hemihydrate, 20 to 55 weight percent hydraulic cement, 0.2 to 3.5 weight percent lime, and 5 to 25 weight percent active pozzolan (activepozzolan), the continuous phase being uniformly reinforced with alkali-resistant glass fibers and containing a uniform distribution of lightweight filler particles comprising uniformly distributed ceramic microspheres.

3. The system of claim 2, wherein the ceramic microspheres have an average particle size from 50 to 250 microns and/or fall within a particle size range of 10 to 500 microns.

4. The system of claim 1, wherein the panel has been formed from, each on a dry basis: 35 to 58 weight percent of the reactive powder; 6 to 17 weight percent of the glass fiber; and 34 to 49 weight percent of at least one of the lightweight fillers selected from the group consisting of ceramic microspheres, glass microspheres, fly ash cenospheres (cenospheres), or perlite.

5. The system of claim 1, wherein the panel has been formed from, each on a dry basis: 49 to 56 weight percent of the reactive powder; 7 to 12 weight percent of the glass fiber; and 35 to 42 weight percent ceramic microspheres having a particle density of 0.50 to 0.80 g/mL.

6. The system of claim 1, wherein the filler comprises uniformly distributed glass microspheres and/or fly ash cenospheres having an average diameter of about 10 to 350 microns.

7. The system of claim 1, wherein the panel is formed from, each on a dry basis: 42 to 68 weight percent of the reactive powder; 5 to 15 weight percent of the glass fiber; 23 to 43 weight percent ceramic spheres; and up to 1.0 wt% glass microspheres.

8. The system of claim 2, wherein the panel comprises a core comprising the continuous phase resulting from curing an aqueous mixture of reactive powders comprising (on a dry basis) 35 to 75 wt% calcium sulfate alpha hemihydrate, 20 to 55 wt% hydraulic cement, 0.2 to 3.5 wt% lime, and 5 to 25 wt% active pozzolan, the continuous phase being uniformly reinforced with the alkali-resistant glass fibers and containing the lightweight filler comprising uniformly distributed ceramic microspheres, and further comprising at least one outer layer, each of the outer layers comprising a continuous phase resulting from curing an aqueous mixture of reactive powders comprising (on a dry basis) 35 to 75 wt% calcium sulfate alpha hemihydrate, 20 to 55 wt% hydraulic cement, 0.2 to 3.5% by weight lime and 5 to 25% by weight of an active pozzolan, the continuous phase being uniformly reinforced with alkali-resistant glass fibers, and the lightweight filler particles having a particle specific gravity of from 0.02 to 1.00 and an average particle size of about 10 to 500 microns, at least one outer layer having a reduced phase density relative to the core.

9. The system of claim 8, wherein the outer layer has been formed from, each on a dry basis: 42 to 68 weight percent of the reactive powder; 5 to 15 weight percent of the glass fiber; up to 1.0 wt% glass microspheres having an average diameter of about 10 to 350 microns; and 23 to 43 weight percent of the lightweight filler particles comprising ceramic spheres.

10. The system of claim 1, wherein the panel has a thickness of about 1/4-1 and 1/2 inches (6.3-38.11 mm).

11. The system of claim 8, wherein the outer layer has a thickness of about 1/32-4/32 inches (0.8-3.2 mm).

12. The system of claim 1 wherein the system having 3/8-3/4 inch (9-19mm) thick SCP panels to laterally support a metal framing in mechanical and/or adhesive form has a nominal wall shear capacity of 200 to 1200 pounds per linear foot when tested according to ASTM E-72.

13. The system of claim 1 wherein the system having 3/8-3/4 inch (9-19mm) thick SCP panels to laterally support a metal framing in mechanical and/or adhesive form has a nominal wall shear capacity of 400 to 1200 pounds per linear foot when tested according to ASTM E-72.

14. The system of claim 1, wherein the system having 3/8-3/4 inch (9-19mm) thick SCP panels mechanically and/or adhesively secured to a lateral support metal framing has a nominal wall shear capacity of 800 to 1200 pounds per linear foot when tested according to ASTM E-72.

15. The system of claim 1 wherein the system having 1/2 inch (12.5mm) thick SCP panels mechanically and/or adhesively secured to a lateral support metal frame has a nominal wall shear capacity of 200 to 1200 pounds per linear foot when tested according to ASTM E-72.

16. The system of claim 1 wherein the system having 1/2 inch (12.5mm) thick SCP panels mechanically and/or adhesively secured to a lateral support metal frame has a nominal wall shear capacity of 400 to 1200 pounds per linear foot when tested according to ASTM E-72.

17. The system of claim 1 wherein the system having an 1/2 inch (12.5mm) thick SCP panel and lateral support metal framing has a nominal wall shear capacity of 800 to 1200 pounds per linear foot when tested according to ASTM E-72.

18. The system of claim 1, wherein the glass fibers are monofilaments having a diameter of about 5 to 25 microns and a length of about 0.25 to 3 inches (6.3 to 76 mm).

19. The system of claim 1, wherein the dry density is 65lb/ft³To 95lb/ft³(1041 to 1522kg/m³) The flexural strength (7MPa) of the panel after 48 hours immersion in water is at least 1000psi (7MPa), as measured by the ASTM C947 test.

20. The system of claim 1, wherein the dry density is 65lb/ft³To 95lb/ft³(1041 to 1522kg/m³) The panel of (a) has a flexural strength of at least 1650psi (11.4MPa) after being soaked in water for 48 hours, as measured by the ASTM C947 test.

21. The system of claim 1, wherein the hydraulic cement is portland cement.

22. The system of claim 1, wherein the reactive powder comprises 45 to 65 weight percent calcium sulfate hemihydrate, 25 to 40 weight percent hydraulic cement, 0.75 to 1.25 weight percent lime, and 10 to 15 weight percent active pozzolan.

23. The system of claim 1, wherein the joist comprises a substantially C-shaped member made of metal.

24. The system of claim 1, wherein the shear wall system has a higher specific nominal wall peel shear strength than a structural masonry shear wall system.

25. The system of claim 1 wherein the horizontal shear diaphragm load carrying capacity of the system will not be reduced by more than 25% when exposed to water for 24 hours in a test in which a 2 inch head of water is maintained over 3/8 to 3/4 inch thick SCP panels fastened on a 10 foot by 20 foot metal frame.

26. The system of claim 1 wherein the horizontal shear diaphragm load carrying capacity of the system will not be reduced by more than 20% when exposed to water for 24 hours in a test in which a 2 inch head of water is maintained over 3/8-3/4 inch thick SCP panels fastened on a 10 foot by 20 foot metal frame.

27. The system of claim 1, wherein the system will not absorb more than 0.7 pounds per square foot of water when exposed to water for 24 hours in a test in which a 2 inch head of water is maintained over 3/8-3/4 inch thick SCP panels fastened on a 10 foot by 20 foot metal frame.

28. The system of claim 1 wherein the 10 foot wide by 20 foot long x 3/8-3/4 inch thick SCP panel barrier attached to the 10 foot by 20 foot metal frame will not expand more than 5% when exposed to a 2 inch head of water maintained over the SCP panel fastened on the metal frame for 24 hours.

29. The system of claim 1, wherein each component meets ASTM G-21 testing, wherein the system achieves a rating of approximately 1, and meets ASTM D-3273 testing, wherein the system achieves a rating of approximately 10.

30. The system of claim 1, wherein substantially zero bacterial growth is supported when clean.

31. The system of claim 1, wherein the system is inedible by termites.

32. The system of claim 1, wherein the panel comprises:

a core layer comprising the continuous phase, and

at least one outer layer on each opposing side of the inner layer having a respective other continuous phase resulting from curing an aqueous mixture comprising (on a dry basis) 35 to 70 weight percent reactive powder, 20 to 50 weight percent lightweight filler, and 5 to 20 weight percent glass fibers, the continuous phase being reinforced with glass fibers and containing the lightweight filler particles having a particle specific gravity of from 0.02 to 1.00 and an average particle size of about 10 to 500 microns, wherein the at least one outer layer has a higher percentage of glass fibers than the inner layer.

33. The system of claim 1, wherein the lightweight nature of the system avoids dead load associated with masonry walls.

34. The system of claim 1, wherein the system is non-directional in that the panels of the system can be placed with their long dimension parallel or perpendicular to the metal joists of the frame without loss of strength or load bearing characteristics, wherein the ability of the system to support both dead and live loads without breakage is the same regardless of the orientation of the SCP panel on the metal frame.

35. A method of making the non-combustible shear wall system of claim 1, comprising placing the panel on the metal stud.

36. The method of claim 39, comprising placing the panel on the metal framing element at an ambient temperature of less than 32 ° F (0 ℃).

37. The method of claim 39, comprising placing the panel on the metal framing element when an ambient temperature is less than 20_ (-7.5 ℃).

38. The method of claim 39, wherein the placing step comprises: placing the panel horizontally on the metal framing element by dropping the panel onto the metal framing element such that at least one end of the panel falls at least 2 feet at an ambient temperature of less than 32 ° f (0 ℃); and subsequently vertically reorienting the panels and the metal framing elements.

39. The method of claim 39, wherein the placing step comprises: placing the panel horizontally on the metal framing element by dropping the panel onto the metal framing element such that at least one end of the panel drops 3 to 4 feet at an ambient temperature of less than 32 ° f (0 ℃); and subsequently vertically reorienting the panels and the metal framing elements.

40. The method of claim 39, wherein the panel is placed vertically on the vertically oriented metal framing element.

41. The method of claim 39, wherein the panel is placed horizontally on the horizontally oriented metal framing element.