RU2841113C1 - Formwork for bearing columns - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to the field of construction, namely to the bearing and shaping structural elements of the formwork used in the erection of monolithic buildings and structures for various purposes, namely to the bearing columns formworks. Formwork comprises three sections: lower, middle and upper. Each section consists of parts connected by means of fastening elements to form a rectangle in plane view. Lower flange of lower section in assembled form is horizontal with possibility of installation on mounting surface. Upper flange of lower section is inclined to central vertical axis of future column formwork. Middle section as-assembled is installed between upper and lower sections. Each part of the middle section is made in the form of a horizontally oriented truncated pyramid with a trapezoid in the vertical section, which is installed with its narrow side closer to the central vertical axis of the column formwork. Upper section as-assembled is made similar to design of lower section, installed inverted by 180 degrees symmetrically to lower section relative to horizontal plane between them. Upper flange of the upper section is horizontal with the possibility of supporting beams or floor slabs on it. Upper section lower flange is inclined to central vertical axis of column formwork. All parts of the structure are made of metal.

EFFECT: increased productivity due to the increased strength and rigidity of the formwork, which allows it to act as a load-bearing column during the curing and strength gain of the concrete mixture.

8 cl, 20 dwg

Description

The invention relates to the field of construction, namely to the supporting and form-forming elements of the formwork structure used in the construction of monolithic buildings and structures for various purposes (residential, industrial, etc.), in particular, formwork for supporting columns.

State of the art

As a rule, the column formwork is formed by several panels, the outer sides of which are provided with transverse ribs formed by profiles of various types. C-shaped, T-shaped, made of square or rectangular section profiled pipes. The stiffening ribs are usually made of metal (iron, aluminum). Wood or plastic are also used. The inner part of the panel is made of metal or laminated multilayer plywood. Plastic or wood can also be used. The panels are connected to each other to form a column contour, which is limited by the inner flat sides of all panels. The panels are provided with mutual installation means and detachable means of fixation in a fixed position. For example: the formwork for a square section column consists of four flat panels or two L-shaped panels assembled in a certain way to form the inner space of a square section of the required size, while the height of the panels is usually equal to the height of the future column. Adjustable braces are used to hold the formwork in a vertical position. After installing the formwork around the reinforcement frame, the concrete mixture is poured. After the concrete has reached the required strength, the formwork is dismantled. This usually takes 7-14 days. Then, the beams and floor slabs are installed on the column or the formwork for the monolithic floor slab is installed.

A technical solution is known under patent RU 2258122 C2 E04G 13/02, E04G 17/07 (2000.01), published on 10.08.2005, according to which COLUMN FORMWORK is formed by several panels, the outer sides of which are provided with transverse ribs formed by C-shaped profiles. The panels are connected to each other to form a prismatic contour, which is limited by the inner flat sides of all panels. The panels are provided with mutual installation means and detachable means of fixation in a fixed position. The mutual installation means are made in the form of hinge pins attached to the edges of the panels and corresponding holes, evenly distributed on the panel in the transverse direction. The said openings are made elongated, and the detachable means for fixing the panels in a fixed position are made in the form of a through opening in the rod of each hinge pin, the axis of which has the ability to oscillate relative to the base rigidly attached to the edge of the pin panel, and a sliding element equipped with a wedge-shaped end and installed with the ability to transversely shift and adjust inside the C-shaped profiles so that the wedge-shaped end of the sliding element of one panel can be inserted into the opening of the rod of the hinge pin of the adjacent panel to prevent unwanted separation of the panels. Disadvantage: low productivity, since when using this formwork it is necessary to wait a certain period of time before the concrete mixture in the formwork hardens. Only after this can the formwork be dismantled and the following construction work be performed: installing beams or interfloor slabs.

A technical solution is known according to patent RU 2038975 C1 B28B 7/00 (1995.01), E04G 15/06 (1995.01), published: 09.07.1995, according to which FORMWORK, including frame panels with side elements having openings along the perimeter every 5 cm or at a smaller or greater distance and connecting elements of the panels, characterized in that, in order to simplify the design, it is equipped with connecting tubular beams with side openings and connecting parallelogram frames with openings on all sides every 5 cm or at a smaller or greater distance, and the connecting elements are made in the form of flat squares with protrusions and hooks. Disadvantage: low productivity, since when using this formwork it is necessary to wait a certain period of time before the concrete mixture in the formwork hardens, in addition, a lot of time is spent assembling the column formwork structure, as well as its subsequent dismantling.

A technical solution is known according to patent RU 2211901 C2 E04G 11/20 (2000.01), published: 10.09.2003, according to which a UNIVERSAL FORMWORK KIT contains prefabricated panel elements in the form of modular panels, formwork stabilization elements in the form of adjustable-length diagonals and formwork movement elements made in the form of wheels, one of which is fixed at the end of the diagonal. It is equipped with a connecting element, corner and end corner inserts, wherein the connecting element, corner and end corner inserts are made in the form of rigid profiled beams with elements of their detachable connection with the panel elements, and the wheel fixed at the end of the diagonal is made with the possibility of its vertical movement, and the other is fixed on the panel element. Disadvantage: low productivity, since when using this formwork it is necessary to wait a certain period of time before the concrete mixture in the formwork hardens, in addition, a lot of time is spent assembling the column formwork structure, as well as its subsequent dismantling.

A technical solution is known under patent RU 2326216 C2 E04G 9/02 (2006.01) E04G 11/08 (2006.01), published: 10.06.2008, according to which a HINGED FORMWORK SHIELD contains two profile elements, the cross-section of each of which is formed by two parallel bases, which are connected to each other by two parallel walls lying in planes perpendicular to the bases. Notches are made on the wall to form three support platforms on the outer side of the profile element. A tail is made on the wall as its continuation, and a recess is made on the wall, which serves to accommodate the clamping cams of the lock when connecting the formwork shields. A console with an endpiece extends from the base adjacent to the tailpiece and from the wall with the recess, in which an opening for the shield axis is located. Disadvantage: low productivity, since when using this formwork it is necessary to wait a certain period of time before the concrete mixture in the formwork hardens, in addition, a lot of time is spent assembling the column formwork structure, as well as its subsequent dismantling.

Thus, many different variants of removable, collapsible formwork are known from the state of the art, which differ from each other in the design and dimensions of the panels, materials of manufacture, assembly options, design of fixing mechanisms and devices, etc. However, they all have a significant drawback: when using formwork of a known design, it is necessary to wait a certain period of time before the concrete mixture in the formwork hardens. Only after this can the formwork be dismantled and the following construction work be carried out, beams or interfloor slabs be installed. In addition, most formwork variants take a lot of time to assemble the column formwork structure, as well as its subsequent dismantling. Another drawback is the need to use scaffolding from which the concrete mixture is poured and vibrated. These can be scaffolding, scaffolding, towers, etc., hung on the formwork. Therefore, the construction of a building, especially a multi-story one, where each floor is poured with concrete no earlier than the pouring of the lower floor has reached the required hardness, is delayed for a long period of time.

The disadvantages of known technical solutions are eliminated by the claimed invention.

The objective of the invention is to design a high-strength formwork for load-bearing columns, which would be temporarily load-bearing for a period of time until the concrete mixture gains the required strength. That is, the installation of beams and interfloor slabs is carried out directly on the formwork, without waiting for the concrete mixture to harden inside the formwork. Thus, the formwork, during the curing and strength gain of the concrete mixture, acts as a load-bearing column.

The essence of the invention

The formwork is distinguished by the fact that it is temporarily load-bearing for a period of time until the concrete mixture gains the required strength. That is, the installation of beams and interfloor slabs is carried out directly on the formwork, without waiting for the concrete mixture to harden inside the formwork. Thus, the formwork, during the curing and strength gain of the concrete mixture, acts as a load-bearing column or wall.

Let us consider the example of formwork for a column with a square cross-section. To increase the load-bearing capacity, the formwork is made entirely of metal (iron). The lateral stiffeners, unlike standard formwork, are located predominantly vertically and are made of a square or rectangular section profile pipe with a thicker wall than standard formwork (standard formwork has a wall thickness of 1.5-5 mm, in the claimed design it is 5-10 mm). Alternatively, the formwork can be made in the form of two L-shaped parts connected to each other in a square using a rigid detachable connection, such as bolts. Also, for ease of installation, it is possible to hinge the two parts of the formwork on one side and use bolts on the other. Connections of formwork parts using other options used in standard formwork (specialized locks, clamps, clamps, ties, etc.) are less effective, since in this case higher rigidity and strength of the formwork is required.

The formwork for supporting columns of the claimed design contains parts made entirely of metal, the lateral stiffening ribs are located mainly vertically, made of a square or rectangular section profile pipe with a wall thickness of 5-10 mm. Alternatively, the formwork can be made in the form of two L-shaped parts connected to each other in a rectangle using bolts. Also, for ease of installation, a hinged connection of two parts of the formwork on one side and with bolts on the other is possible.

The main differences between this formwork and the standard one

Firstly, higher mechanical rigidity and strength, since it is necessary to withstand not only the pressure of the concrete mixture inside the formwork, but also the weight of the beams and floor slabs of the next floor (floors) placed on top of the formwork. This is ensured by making the formwork parts from metal.

Secondly, the possibility of dismantling the formwork under pressure. After the concrete inside the formwork has hardened to the required value, it must be dismantled. But since the next floor slabs are laid on the formwork, it is in a "clamped" position and it is not possible to dismantle the typical formwork. Therefore, the declared formwork in assembled form is not a single element along the entire height (like the typical one), but is divided into three sections: lower, middle and upper. The lower section contains two L-shaped parts connected with bolts into a rectangle (as a special case - a square). The lower shelf of the lower section is horizontal, with which the formwork is installed on the mounting surface. The upper shelf of the lower section is made with a slope towards the center of the formwork. The upper section has the same design as the lower one, only it is turned 180 degrees: that is, the upper shelf of the upper section is horizontal, the beams or floor slabs are supported on it, while the lower shelf is made with a slope towards the center of the formwork. The middle section acts as a kind of lock and contains four separate parts of the same vertical section, which are assembled using a rigid detachable connection, for example, bolts into a rectangle in the plan (a special case is a square). The upper and lower shelves of each part of the middle section are oppositely inclined and form a pyramid, in the vertical section - a trapezoid, the narrow part of which is directed towards the center of the column. The assembled middle section is installed between the upper and lower sections. For example: if the height of the future column should be 3 m, then the upper and lower sections have a height of 1.4 m, and the middle section (insert) is 0.2 m.

Alternatively, the middle section parts (each) can be made in the form of a solid all-metal wedge in the form of a pyramid with a base of 20 - 50 mm, a vertical section in the form of a trapezoid, the narrow part of which is directed to the center of the formwork. Each part of the middle section is made with through holes for fasteners, all three sections are fastened with bolts with conical washers.

The order of formwork assembly. The lower section of the formwork is assembled (screwed with bolts) and installed around the reinforcement cage of the future column. The middle section is assembled into a rectangle in plan (a special case, a square) and placed on the lower one. The lower and middle sections are screwed together with bolts. On the floor, the upper section is assembled into a rectangle in plan (a special case, a square) and installed on top of the middle section using a crane. The upper section is also bolted to the middle part. All three sections are fixed with bolts by side elements (beams), providing additional rigidity and strength to the entire structure, as well as the desired position of all formwork sections relative to each other. Adjustable braces (of any suitable design) are installed and with their help the assembled formwork is installed and fixed in a vertical position.

Further work. Reinforced concrete beams are placed on the upper shelves of the formwork. The beams have reinforcement extensions at the ends. Floor slabs are mounted on the beams. This forms a practically finished floor of the next floor. From this floor, concrete mix is poured into the formwork and then vibrated. At the same time, the beam-column joint is monolithically filled. It is also possible to leave gaps between the floor slabs where they rest on the beams and fill these gaps with concrete. This achieves a higher degree of monolithicity of the building frame. To reduce the "tightness" of the formwork for easier dismantling, as well as to prevent cracks, shrinkage-free concrete is used. After this, without waiting for the concrete mix to harden inside the formwork, it is possible to install reinforcement cages and formwork for the columns of the next floor almost immediately, since the supporting formwork of the column holds the floor of the floor.

The formwork for load-bearing walls can be made similar to the design of the formwork for load-bearing columns. It differs from the formwork for square or rectangular columns in that additional blocks are added. Their number is selected depending on the required length of the wall. The blocks are connected to each other and to the corner pieces using bolts. Each formwork block consists of three sections, like the column formwork blocks. When assembling the formwork, to prevent the concrete mixture from spreading between the wall formwork blocks, metal spacer tubes are additionally installed, inside which tightening studs with nuts are placed. When disassembling the formwork after the concrete mixture has hardened, first unscrew the nuts on the tightening studs. The studs are removed. Then the formwork is disassembled in the same order as the column formwork. The spacer tubes remain in the wall body or, after dismantling the formwork, are knocked out and reused. For easier dismantling, the tube can be made in the form of a cone with a slight slope, that is, the outer diameter of the tube on one side is larger than on the other by several millimeters.

Dismantling the formwork. After the concrete has reached the required strength, in a few days, the formwork is dismantled. The adjustable braces are dismantled (removed), then the side elements (beams) are dismantled (unscrewed), then the bolts holding the middle section in the assembled position are unscrewed, as well as the bolts connecting the middle section to the upper and lower sections. Since the middle section has a vertical cross-section in the form of a trapezoid, horizontally oriented, located with the narrow part to the center of the formwork, then when disassembled, each individual part of the middle section is easily removed to the outside. By removing the middle section, we eliminate the "clamping" of the entire formwork structure and the remaining sections are freely dismantled. First, the lower section is unscrewed and removed. Then the connections of the upper section are loosened. Holding it, it is lowered down (to the floor) and then on the floor, at a height convenient for work, it is finally disassembled and dismantled.

In this case, the working joints of the columns are arranged at the level of the floor slabs, which facilitates the installation of the formwork, which increases the degree of technology in the manufacture of building frames using the formwork of the claimed design. There is no need to use scaffolding, no time is wasted on their installation and dismantling. The time for assembling and disassembling the formwork is reduced due to its well-thought-out design compared to formwork from individual panels. And the most important advantage is that there are no long downtimes in work due to waiting for the concrete to gain strength in the formwork of the columns of each floor. All together, it significantly increases productivity and reduces construction time when erecting monolithic buildings and structures. In addition, due to its high strength, the formwork can withstand a large number of working cycles, i.e. it is more durable.

The technical result is an increase in productivity due to the increased strength and rigidity of the formwork, which allows it to act as a load-bearing column during the curing and strength gain of the concrete mixture.

The technical result is achieved by the design of formwork for load-bearing columns, containing three sections: lower, middle and upper; each section consists of parts connected by means of fasteners into a rectangle in plan, the lower shelf of the lower section in assembled form is horizontal with the possibility of installation on the mounting surface, the upper shelf of the lower section is made with a slope towards the central vertical axis of the formwork of the future column; the middle section in assembled form is installed between the upper and lower sections, each part of the middle section is made in the form of a horizontally oriented truncated pyramid with a trapezoid in vertical section, installed with the narrow side closer to the central vertical axis of the column formwork; the upper section in assembled form is made similar to the design of the lower section, installed turned 180 degrees symmetrically to the lower section relative to the horizontal plane between them, while the upper shelf of the upper section is made horizontal with the possibility of supporting beams or floor slabs on it, and the lower shelf of the upper section is made with a slope towards the central vertical axis of the column formwork; while the formwork contains stiffeners, side elements, adjustable struts and all formwork parts are made of metal.

In this case, the middle section consists of parts assembled by a rigid detachable connection using bolts into a rectangle in plan; in this case, the upper and lower shelves of each part of the middle section are made with a counter slope towards the central vertical axis of the column formwork and the surfaces of the part form a trapezoid in vertical section, the narrow side of which is installed closer to the central vertical axis of the column formwork.

As a special case, each detail of the middle section is made of a hollow frame made of metal plates in the form of a truncated pyramid, which in vertical section has the appearance of a trapezoid, the narrow side of which is installed closer to the central vertical axis of the column formwork, with holes for fastening elements.

Another special case, when each detail of the middle section is made of solid metal in the form of a truncated pyramid, having in the vertical section the form of a trapezoid, the narrow side of which is installed closer to the central vertical axis of the column formwork, with through holes with the possibility of fastening all three sections with bolts with conical washers. The lateral stiffening ribs are located vertically.

The stiffening ribs are made from a rectangular section profile pipe with a wall thickness of at least 5 mm.

As a special case, the parts of the upper and lower sections of the formwork are made with a hinged connection of two parts of each section on one side and holes for fasteners on the other.

Another special case is when the parts of the upper and lower sections of the formwork are made in the form of two L-shaped parts of each section, connected with bolts into a rectangle in plan.

The essence of the claimed invention is explained by the images in Figs. 1 - 20.

Fig. 1. Variants of typical formwork of known technical solutions.

Fig. 2. Side view of the assembled formwork.

Fig. 3. Upper section, top view.

Fig. 4. Middle section, top view.

Fig. 5. Upper section, section A - A.

Fig. 6. Middle section, section B - B. (a) - hollow welded (frame), (b) - solid all-metal.

Fig. 7. Assembled formwork, section B-B

Fig. 8. Assembled formwork, section G-G

Fig. 9. The middle section made of solid metal parts, in vertical section

Fig. 10. Assembled formwork with beams and floor slabs

Fig. 11. Installation of beams on formwork

Fig. 12. Installation of floor slabs

Fig. 13. Monolithic part of the ceiling

Fig. 14. Installation of formwork for the next floor

Fig. 15. Load-bearing interfloor insert

Fig. 16. Beam variants: (a) - typical beam and slab, (b) - beam and slab with reinforcement extensions, (c) - U-shaped beam with reinforcement cage.

Fig. 17. Column formwork with monolithic floor slab formwork

Fig. 18. Reinforcing insert for monolithic floor slab

Fig.19. Upper section of the formwork for a rectangular column

Fig. 20. Upper section of the formwork of the load-bearing wall.

Where 1 is the vertical stiffener;

2 - horizontal stiffener;

3 - adjustable brace;

4 - upper section of formwork;

5 - middle section of formwork;

6 - lower section of formwork;

7 - side element (beam);

8 - connecting bolt;

9 - hollow welded middle section part (frame);

10 - solid metal middle section part;

11 - conical washer;

12 - reinforced concrete beam;

13 - hollow-core floor slab;

14 - reinforcement;

15 - connecting sleeve for fittings;

16 - concrete mix;

17 - load-bearing interfloor insert;

18 - lightweight formwork;

19 - column reinforcement frame;

20 - reinforcing insert for monolithic floor slab;

21 - formwork shield of the floor slab;

22 - supporting beam;

23 - telescopic mounting stand;

24 - formwork block for walls;

25 - spacer tube;

26 - tightening pin.

Example of implementation.

The formwork for load-bearing columns contains three sections: lower 6, middle 5 and upper 4; each section consists of parts connected with fasteners into a rectangle in plan (a special case is a square). The lower shelf of the lower section 6 in assembled form is horizontal with the possibility of installation on the mounting surface, the upper shelf of the lower section 6 is made with a slope to the central vertical axis of the future column; the middle section 5 in assembled form is installed between the upper 4 and lower 6 sections, each part of the middle section 5 is made in the form of a horizontally oriented truncated pyramid with a trapezoid in vertical section, located with a narrow part closer to the central vertical axis of the column. The upper section 4 in assembled form is made similar to the design of the lower section 6, installed turned 180 degrees symmetrically to the lower section 6 relative to the horizontal plane between them, wherein the upper shelf of the upper section 4 is horizontal with the possibility of supporting beams or floor slabs on it, and the lower shelf of the upper section 4 is made with a slope towards the central vertical axis of the column. The middle section 5 consists of four parts assembled by a rigid detachable connection (for example, using bolts) into a rectangle in plan (the cross-section of the future column); wherein the upper and lower shelves of each part of the middle section 5 are made with a counter slope towards the central vertical axis of the column and the surfaces of each part form a trapezoid in the vertical section, the narrow part of which is located closer to the central vertical axis of the column.

Each part of the middle section 5 is made of a hollow frame 9, for example, welded, from metal plates in the form of a horizontally oriented truncated pyramid, with a trapezoid in the vertical section, the narrow side of which is located closer to the central vertical axis of the column, with holes for fastening elements 8. Alternatively, each part of the middle section 5 can be made of a solid all-metal 10 in the form of a truncated pyramid, having a trapezoid in the vertical section, the narrow side of which is located closer to the central vertical axis of the column, with through holes with the possibility of fastening all three sections with bolts 8 with conical washers 11. The lateral stiffening ribs 1 are located predominantly vertically and are made of a rectangular section profile pipe with a wall thickness of at least 5 mm.

As an option, the parts of the upper 4 and lower 6 sections of the formwork are made with a hinged connection of two parts of each section on one side and holes for fasteners on the other. Another option is when the parts of the upper 4 and lower 6 sections of the formwork are made in the form of two L-shaped parts of each section, connected with bolts into a rectangle in the plan.

For wall formwork, additional formwork blocks 24 are used depending on the required wall length, wherein each wall formwork block 24 consists of three sections 4,5,6, like the column formwork, the blocks are connected to each other and to the corner pieces by a rigid detachable connection. Between the wall formwork blocks 24, metal spacer tubes 25 are installed, inside which there are tightening pins 26 with nuts.

Higher mechanical rigidity and strength of the formwork is achieved by manufacturing parts from metal, for example, the side stiffeners 1 are made from a square or rectangular section profile pipe with a wall thickness of at least 5 mm, since it is necessary to withstand not only the pressure of the concrete mixture 16 inside the formwork, but also the weight of the beams 12 and floor slabs 13 of the next floor (floors) placed on top of the formwork.

The advantage of the claimed design is the possibility of dismantling the formwork under pressure. After the concrete inside the formwork has hardened to the required value, it must be dismantled, but since the floors of the next floor are laid on the formwork, it is in a "clamped" position and, as a rule, it is not possible to dismantle the typical formwork. Therefore, the claimed supporting formwork in assembled form is not a single element along the entire height (as in the typical one), but is divided into three sections (Fig. 2-9) lower 6, middle 5 and upper 4. The lower section 6 consists of four parts or, as an option, of two L-shaped parts connected with bolts 8 into a rectangle (a special case - into a square). The lower shelf is horizontal, with which the formwork is installed on the mounting surface. The upper shelf of the lower section 6 is made with a slope towards the center of the future column. The upper section 4 has the same design as the lower one, only it is turned by 180 degrees, i.e. the upper shelf is horizontal, the beams 12 or floor slabs 13 are supported on it, while the lower shelf of the upper section 4 is made with a slope towards the center of the column. The middle section 5 acts as a kind of "lock" and consists of four separate parts 9 (10) of the same transverse (vertical) section, which are assembled using bolts 8 into a rectangle (a special case, a square). The upper and lower shelves of part 9 of the middle section are inclined in opposite directions and form a horizontally oriented truncated pyramid with a trapezoid in the vertical section, the narrow part of which is directed towards the center of the column. The middle section 5 in assembled form is installed between the upper 4 and lower 6 sections. For example: if the height of the future column should be 3 m, then the upper 4 and lower 6 sections each have a height of 1.4 m, and the middle section 5 (insert) is 0.2 m. Alternatively, the part of the middle section 5 can be made in the form of a solid all-metal wedge (a truncated pyramid with a vertical section in the form of a trapezoid) 10 with a base height of 20 - 50 mm. All three sections are fastened with a rigid detachable connection with fasteners, for example, a bolt 8 with conical washers 11.

The order of formwork assembly. The lower section 6 is assembled (bolted) and installed in the required place, for example, around the reinforcement cage 19 of the future column. The middle section 5 is assembled into a rectangle (a special case, a square) and placed on the lower section 6. The lower 6 and middle 5 sections are bolted together with 8. The upper section 4 is assembled into a rectangle (a special case, a square) on the floor and installed on top of the middle section 5 using a crane. The upper section 4 is also bolted to the middle section 5. All three sections are fixed with bolts by the side elements (beams) 7, providing additional rigidity and strength to the entire structure, as well as the correct position of all parts of the formwork relative to each other. Adjustable braces 3 are installed and used to fix the assembled formwork in a vertical position.

Further work. Reinforced concrete beams 12 with reinforcement extensions 14 at the ends are placed on the upper shelves of the formwork. Floor slabs 13, lightweight formwork 18, load-bearing interfloor inserts 17, a reinforcing insert for a monolithic floor slab 20, a floor slab formwork panel 21 are mounted on the beams 12. The load-bearing beam 22 and the telescopic mounting rack 23 support the floor slab formwork panel 21. This forms the floor of the next floor. From this floor, concrete mix 16 is poured into the formwork and then vibrated. At the same time, the beam-column joint is monolithically cast. If necessary for the height of the column, connecting couplings 15 for reinforcement 19 are used. It is also possible to leave gaps between the floor slabs 13 in the places of their support on the beams 12 and fill these gaps with concrete. This achieves a higher degree of monolithicity of the building frame. After this, without waiting for the concrete mixture to harden inside the formwork, it is possible to install reinforcement cages and formwork for the columns of the next floor almost immediately, since the supporting formwork of the column holds the floor of the floor.

Dismantling the formwork. After the concrete has reached the required strength in a few days, dismantle the formwork. Dismantle (remove) the adjustable braces 3; dismantle the side elements (beams) 7; unscrew the bolts 8 holding the middle section in the assembled position, as well as the bolts 8 connecting the middle section 5 with the upper 4 and lower 6 sections. Since the middle section 5 has a vertical cross-section in the form of a trapezoid, the narrow part of which is directed toward the center of the formwork, then when disassembled, each individual part of the middle section 5 is easily removed. By removing the middle section 5, we eliminate the “clamping” of the entire formwork structure and the remaining sections are freely dismantled. First, the lower section 6 is unscrewed and removed. Then the connections of the upper section 4 are loosened. Holding it, it is lowered down onto a horizontal surface (on the floor) and then on the floor, at a height convenient for work, it is finally disassembled and dismantled.

The formwork for load-bearing walls differs from the formwork for square or rectangular columns in that additional wall formwork blocks 24 are added. Their number is selected depending on the required wall length. The blocks are connected to each other and to the corner pieces using bolts. Each formwork block consists of three sections, just like the column formwork blocks. When assembling the formwork, to prevent the concrete mix from spreading between the wall formwork blocks 24, metal spacer tubes 25 are additionally installed, inside which tightening pins 26 with nuts are placed. When disassembling the formwork after the concrete mix has hardened, first unscrew the nuts on the tightening pins 26, and remove the pins. Then disassemble the formwork in the same order as the column formwork. Spacer tubes 25 are left in the wall body or, after dismantling the formwork, are knocked out and reused.

The increase in the degree of manufacturability in the manufacture of building frames using the claimed formwork consists in the fact that the working joints of the columns are arranged at the level of the floor slabs, which facilitates the installation of the formwork, there is no need to use scaffolding, no time is wasted on assembly and dismantling. Less time is spent on assembly and disassembly of the formwork compared to formwork from separate panels, there are no downtimes in work due to waiting for the concrete to gain strength in the formwork of columns and load-bearing walls of each floor, the advantage is the possibility of quick, easy and inexpensive assembly and disassembly of the formwork, which does not require high qualification of workers. The claimed design ensures an increase in the rigidity and strength of the profile elements that make up the formwork, which leads to the preservation of the geometric immutability of the structure when exposed to loads, and in increasing its operational manufacturability, and this allows the formwork structure to be load-bearing and to achieve the declared technical result - increased construction productivity.

Claims (8)

1. Formwork for load-bearing columns, comprising three sections: lower, middle and upper; each section consists of parts connected by means of fasteners into a rectangle in plan, the lower shelf of the lower section in assembled form is horizontal with the possibility of installation on the mounting surface, the upper shelf of the lower section is made with a slope towards the central vertical axis of the formwork of the future column; the middle section in assembled form is installed between the upper and lower sections, each part of the middle section is made in the form of a horizontally oriented truncated pyramid with a trapezoid in vertical section, installed with the narrow side closer to the central vertical axis of the column formwork; the upper section in assembled form is made similar to the design of the lower section, installed turned 180 degrees symmetrically to the lower section relative to the horizontal plane between them, while the upper shelf of the upper section is made horizontal with the possibility of supporting beams or floor slabs on it, and the lower shelf of the upper section is made with a slope towards the central vertical axis of the column formwork; while the formwork contains stiffeners, side elements, adjustable struts and all formwork parts are made of metal. 2. Formwork for load-bearing columns according to paragraph 1, characterized in that the middle section consists of parts assembled by a rigid detachable connection using bolts into a rectangle in plan; wherein the upper and lower shelves of each part of the middle section are made with a counter slope in the direction of the central vertical axis of the column formwork and the surfaces of the part form a trapezoid in vertical section, the narrow side of which is installed closer to the central vertical axis of the column formwork. 3. Formwork for load-bearing columns according to paragraph 1, characterized in that each part of the middle section is made of a hollow frame made of metal plates in the form of a truncated pyramid, having the appearance of a trapezoid in vertical section, the narrow side of which is installed closer to the central vertical axis of the column formwork, with openings for fastening elements. 4. Formwork for load-bearing columns according to paragraph 1, characterized in that each part of the middle section is made of solid metal in the form of a truncated pyramid, having the appearance of a trapezoid in vertical section, the narrow side of which is installed closer to the central vertical axis of the column formwork, with through holes with the possibility of fastening all three sections with bolts with conical washers. 5. Formwork for load-bearing columns according to item 1, characterized in that the lateral stiffening ribs are located vertically. 6. Formwork for load-bearing columns according to paragraph 1, characterized in that the stiffening ribs are made from a rectangular section profile pipe with a wall thickness of at least 5 mm. 7. Formwork for load-bearing columns according to paragraph 1, characterized in that the parts of the upper and lower sections of the formwork are made with a hinged connection of two parts of each section on one side and openings for fasteners on the other. 8. Formwork for load-bearing columns according to paragraph 1, characterized in that the parts of the upper and lower sections of the formwork are made in the form of two L-shaped parts of each section, connected with bolts into a rectangle in plan.