RU2852375C1 - Vertical joint of prefabricated diaphragms of wooden buildings with glue-screw connections - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: butt joint is intended for the construction of vertical joints of diaphragms of buildings with a frame system made of prefabricated wooden structures. The vertical joint of prefabricated diaphragms of wooden buildings with glue-screw connections includes cutouts in the joined diaphragms, in which steel connecting parts in the form of square profile tubes are placed, bolts with metric thread are passed through the holes in the walls of which, the cutouts are made triangular, blind holes are drilled in the centre of their surfaces, the walls of which are impregnated with glue and into which studs with metric thread are screwed protruding from them, wherein the diameter of the holes is 2 mm less than the diameter of the studs, wherein nuts are screwed onto the studs to half the length of the nuts, which are located flush with the edges of the triangular cutouts in the holes drilled in the joined diaphragms to the depth of the nuts and impregnated with glue, and bolts passed through the holes in the walls of the square profile tubes are screwed into the nuts, wherein the square profile tubes are equipped inside with two stiffening diaphragms in the form of steel square plates, at least one of which has a hole for making bolted connections from inside the connecting part, and wooden overlays are installed on screws on both sides of the steel connecting part flush with the front surfaces of the joined wooden structures.

EFFECT: increase in shear strength and rigidity of the vertical butt joint of prefabricated wooden structures of building diaphragms, simplification of installation technology.

1 cl, 3 dwg

Description

Field of technology to which the invention relates

The invention relates to the field of construction and is intended for the installation of vertical joints between diaphragms of buildings with a frame system made of prefabricated wooden structures and is aimed at ensuring shear strength, rigidity and seismic resistance of buildings.

State of the art

The closest analogue to the proposed butt joint in terms of its combination of features is the connection of wall structures made of cross-laminated timber, consisting of metal box-shaped profile parts with an eye, inside which a beam of glued timber made of beech veneer is installed, secured at the joint to the corners of the wall panels, cut at an angle of 45 degrees, with self-tapping screws with full thread and two steel plates, which are attached to the ears of the metal profile parts using bolted connections [X-RAD Rothoblaas connecting system] .

The disadvantage of this butt joint of wooden structures is the complexity of assembly due to the need to ensure the alignment of holes in the ears of the parts and plates for the installation of bolted connections, the low strength of the screw connections of the parts and wooden panels, and insufficient shear rigidity of the joint for use in building diaphragms due to the presence of a large number of connections.

The closest analog to the proposed butt joint, based on its combined features and adopted as a prototype, is a butt joint between diaphragms of a precast reinforced concrete bridge structure. This joint includes a connecting device located in the cutouts of the walls of the joined diaphragms and concrete for grouting. The connecting device consists of a metal tubular key, spaced apart from the cutout walls and equipped with sealing annular elements, securely fitted to the annular sections of the key. A pair of pressure plates, secured on both sides of the diaphragm walls by a tie bolt passed through the tubular key, and toroidal sealing elements positioned between the diaphragm walls and the pressure plates. The monolithic concrete is placed in the gap between the tubular key and the walls of the cutouts in the joined diaphragms, with at least one of the pressure plates being made with an opening for injecting polymer concrete [USSR Author's Certificate No. SU 1182101 A1, published 30.09.1985].

A disadvantage of the well-known butt joint of diaphragms is the complexity of design and installation, due to the need to grout the joint with polymer concrete on-site. This butt joint technology cannot be used for joining wooden diaphragms of buildings, as the pressure plates and pressure bolt protrude beyond the surface of the wall diaphragm and will interfere with cladding or façade installation.

Technical result

The technical result consists in increasing the shear strength and rigidity of the vertical butt joint of prefabricated wooden structures of building diaphragms, and in simplifying the installation technology.

Disclosure of the essence of the invention

The solution to the technical problem is achieved in that the vertical joint of diaphragms from prefabricated wooden structures, including connecting parts and adhesive-screw joints, is characterized in that, in order to increase the strength and rigidity of the butt joint, as well as to reduce labor intensity, prefabricated glued wooden structures are equipped at the manufacturing plant with adhesive-screw joints using studs with metric threads along the entire length and couplings that are screwed onto the ends of the studs protruding inside holes pre-drilled for them in the wood by half the length of the couplings, located flush with the edges of the triangular cutouts, and the connecting parts, made in the form of metal keys from a square tube, in the walls of which there are holes for bolts, are equipped inside with two stiffening diaphragms in the form of steel square plates, at least one of which has an opening for the arrangement of bolted connections from the inside of the part by screwing bolts into the couplings through holes in the walls of the pipe.

Brief description of the drawings

The invention is explained by drawings.

Fig. 1 shows a fragment of a vertical joint of diaphragms made of prefabricated wooden structures.

Fig. 2 shows the proposed butt joint.

Fig. 3 shows the proposed butt joint in section A-A.

Designations adopted in Fig. 1, 2, 3:

1 - Jointed wooden structure;

2 - Triangular cutout in a wooden structure;

3 - Steel connecting part;

4 - Stud with metric thread along the entire length;

5 - Coupling with metric thread;

6 - Square steel tube with holes in the walls;

7 - Bolt with metric thread;

8 - Steel square plate with or without hole;

9 - Wooden overlay;

10 - Screw (structural self-tapping screw).

Fig. 1 shows a fragment of a vertical joint of diaphragms made of prefabricated wooden structures; Fig. 2 shows the proposed butt joint; Fig. 3 - section A-A.

The vertical joint of glued timber structures of the wall diaphragm includes steel connecting parts 3 placed in triangular cutouts 2 of the joined structures 1 and glue-screw connections using studs with metric threads along the entire length 4, onto the ends of which couplings 5 are screwed, the studs 4 protrude inside the holes pre-drilled for them in the wooden structures 1 by half the length of the couplings 5, located flush with the edges of the triangular cutouts 2. The connecting part 3 is made of a square profile pipe 6, in the walls of which there are holes for bolts 7, is equipped inside with two stiffening diaphragms in the form of steel square plates 8, at least one of which has an opening for the device of bolted connections when fastening the connecting part 3 to the studs with metric threads 4 by screwing bolts 7 into the couplings 5, the connecting parts 3 are covered on both sides with wooden pads 9 installed flush with the front surfaces of the joined structures 1 on screws 10.

Implementation of the invention

The butt joint is performed as follows.

Blind holes 2 mm smaller than the diameter of studs with metric threads 4 are drilled perpendicularly to the edges of wooden structures 1 at the center of the surfaces of triangular cutouts 2. These holes are then reamed to a diameter several millimeters larger than the outer diameter of couplings 5 to a depth equal to their length. The studs 4 are screwed into the holes of wooden structures 1, the walls of which are pre-impregnated with glue, so that the ends of the studs 4 protrude in the holes for couplings 5 by half their length. Couplings 5 are then screwed onto the free ends of the studs 4 flush with the edges of triangular cutouts 2. The joined wooden structures 1 are installed in the design position and connected to each other using connecting parts 3, which are installed between the structures at the locations of the triangular cutouts. Next, through the hole in the diaphragm 8, bolted connections are made from the inside of the part by screwing bolts 7 into couplings 5 through the holes in the walls of part 3. The connecting part 3 is closed on both sides with wooden plates 9, which are installed flush with the front surfaces of the joined structures 1 on screws 10.

The butt joint design works as follows.

Connectors 3, secured to studs 4 of the adhesive-screw joints in timber structures 1 using bolts 7 and couplings 5, absorb shear forces in the precast diaphragms from horizontal loads on the building. These forces, where connecting components 3 are installed, are divided into tensile and compressive forces. Tensile forces are absorbed by the adhesive-screw joints, while compressive forces are absorbed by the abutment of connecting component 3 against the edge surface of triangular cutouts 2 in structures 1.

The proposed joint design is prefabricated and disassemblable, simplifying the installation of buildings constructed from glued laminated timber structures by eliminating the need for welding. Compared to traditional screw-on joints, the use of adhesive-screw joints increases the shear strength of prefabricated diaphragms made of cross-laminated timber, laminated timber, and laminated veneer lumber, and allows for faster construction due to the use of prefabricated structures with maximum factory readiness. To ensure the required damping when calculating the building's resistance to wind and seismic loads, the connecting component design allows for varying the stiffness and ductility of the joint by using different steel grades, varying the thickness of the pipe, and stiffening diaphragms. To ensure the fire resistance of the joint, the connecting component is covered with wooden cover plates on both sides.

Claims (1)

A vertical joint of prefabricated diaphragms of wooden buildings with glue-screw joints, including cutouts in the diaphragms to be joined, in which steel connecting parts are placed in the form of square-section pipes, into the holes in the walls of which bolts with metric threads are passed, characterized in that the cutouts are made triangular, in the center of their surfaces blind holes are drilled, the walls of which are impregnated with glue and into which studs with metric threads protruding from them are screwed, and the diameter of the holes is 2 mm less than the diameter of the studs, while couplings are screwed onto the studs for half the length of the couplings, which are located flush with the edges of the triangular cutouts in holes drilled in the diaphragms to be joined to the depth of the couplings and impregnated with glue, and the bolts passed through the holes in the walls of the square-section pipes are screwed into the couplings, and the square-section pipes are provided inside with two stiffening diaphragms in the form of steel square plates, according to at least one of which has an opening for making bolted connections from the inside of the connecting part, and on both sides of the steel connecting part, flush with the front surfaces of the joined wooden structures, wooden plates are installed on screws.