Reinforced formwork block for compressed and eccentrically compressed reinforced concrete elements
The reinforcement formwork block with T-shaped stiffeners addresses the lack of constrained deformation in existing blocks, enhancing load-bearing capacity and rigidity by anchoring into the concrete core, thus improving structural performance.
Patent Information
- Authority / Receiving Office
- RU · RU
- Patent Type
- Utility models
- Current Assignee / Owner
- FEDERALNOE GOSUDARSTVENNOE BJUDZHETNOE OBRAZOVATELNOE UCHREZHDENIE VYSSHEGO OBRAZOVANIJA NATSIONALNYJ ISSLEDOVATELSKIJ MOSKOVSKIJ GOSUDARSTVENNYJ STROITELNYJ UNIV NIU MGSU
- Filing Date
- 2025-11-19
- Publication Date
- 2026-07-01
AI Technical Summary
Existing reinforced formwork blocks for concrete structures lack the ability to effectively incorporate external steel sheets for constrained deformation, leading to insufficient load-bearing capacity and rigidity, especially in highly loaded and eccentrically compressed elements.
A reinforcement formwork block design featuring a metal frame with T-shaped stiffeners welded to longitudinal steel sheets, forming a box-section, which anchors into the concrete core, limiting transverse deformations and enhancing structural rigidity and load-bearing capacity.
The design increases the load-bearing capacity and deformability of compressed and eccentrically compressed elements by allowing constrained concrete deformation, reducing weight and construction time, while maintaining structural rigidity and reliability.
Smart Images
Figure 00000001
Abstract
Description
[0001] The utility model relates to the field of construction, namely to steel-reinforced concrete structures with external sheet reinforcement, and can be used as a building element for highly loaded compressed and eccentrically compressed parts of high-rise buildings and structures.
[0002] This utility model relates to a precast-monolithic construction method using reinforced formwork blocks for columns and pylons with external sheet reinforcement. The formwork blocks comprise a steel supporting frame consisting of steel sheets with welded T-shaped stiffeners, which serve as formwork during the placement of monolithic concrete and as external reinforcement within the composite steel-reinforced concrete element when supporting the payload. The T-shaped stiffeners, arranged in this manner, without the use of through ties, ensure the inclusion of external steel sheets in creating conditions for constrained concrete deformation under limited transverse deformations, thereby increasing the design resistance of the concrete and the load-bearing capacity of the composite steel-reinforced concrete element.
[0003] The existing state of the art discloses pylons of a beam-less reinforced concrete building frame (RU patent no. 2808630 cl. E 04 B1 / 21, 2023), made in the form of a flat reinforced concrete element of rectangular cross-section in plan, containing at least one transverse concrete recess under the interfloor floor slab for connecting open fragments of longitudinal working reinforcement with the interfloor floor, on the lower part of the pylon - rod releases of the longitudinal working reinforcement for connection with the pylon installed below, in the upper part of the pylon - longitudinal cylindrical holes, in each of which a spirally twisted corrugated metal pipe is placed with the possibility of placing in it the releases of the longitudinal working reinforcement of another pylon installed on top. The disadvantage of the presented type of structure is the large weight while ensuring an ultra-high load-bearing capacity and a weakening of the section in the area of the floor device.
[0004] From the existing level of technology, there are known reinforced formwork blocks that include concrete or reinforced concrete slabs that differ in the methods of connecting them to each other, for example, using connecting elements in the form of: reinforcing bars (USSR Author's Certificate No. 694609 class E 0.4 C 2 / 26, 1979), anchors or crossbars made of angles (USSR Author's Certificate No. 1425291 class E 0.4 C 2 / 26, E 0.4 B 1 / 40 1979), through rigid steel trusses (USSR Author's Certificate No. 1017041 class E 0.4 C 2 / 26 1989), transverse concrete diaphragms (USSR Author's Certificate No. 1534156 class E 0.4 C 2 / 28, 1990), rods with plates (USSR Author's Certificate No. 1559074 cl. E 04 G 9 / 10, 1990), a lattice frame made of fiberglass tubes (RU patent No. 2029840 cl. E 04 G9 / 10, 1995), plastic ties with L-shaped mounting hooks (RU patent No. 2342502 cl.E 04 B 2 / 86, 2008), as well as structural elements that ensure the alignment of slabs during the manufacturing process of the reinforced formwork block for installation in the design position. The disadvantage of these reinforced formwork blocks is their limited scope of use—only for flexible structural elements, such as the use of fairly thick and heavy concrete or reinforced concrete slabs as permanent formwork.
[0005] From the existing level of technology, there are known reinforced formwork blocks (RU patent for invention No. 2037038 dated 09.06.1995, MPKE04C 2 / 26, E04G 9 / 10), containing external and internal metal formwork sheets installed in pairs in a row and one on top of the other, between which, opposite the edges of the sheets joined together, trusses are installed in tiers one on top of the other, having two vertical belts with horizontal crossbars for the external and internal metal formwork sheets connected to each other by welding with upper and lower struts and diagonals, and the vertical belts of the trusses and horizontal crossbars for the internal formwork sheets are made in the form of trays, the ends of the sides of which are hermetically attached to the vertical and horizontal edges of the internal metal formwork sheets joined together, thereby forming a system of hermetically sealed cavities.The combined use of permanent formwork and reinforcement cages increases the speed of construction, while the use of welded joints increases the speed of construction when using automatic welding machines. The reinforcement cage rods are located at a significant distance from the parallel formwork panels to comply with building code requirements for reinforcement embedment into the concrete structure, which protects it from adverse weather conditions and ensures its inclusion in the structural load-bearing capacity of the structure. A disadvantage of these reinforced formwork units is the lack of structural elements that ensure the inclusion of the outer steel sheets in the work to create conditions for constrained deformation of the concrete structure as a whole.
[0006] A prior art discloses a reinforced formwork block and building structure (Russian Federation Patent for Invention No. 2632592 dated August 4, 2016, IPC 04G 11 / 06, E 04G 11 / 36, E04B 2 / 86) comprising a concrete-filled reinforced formwork block comprising a reinforcing cage (sheets of permanent steel fiber reinforced concrete formwork) fastened to the reinforcing cage. A significant drawback of the proposed technology is the combination of metal and steel fiber reinforced concrete products in a single structural unit, requiring the involvement of disparate technologies and specialists in various fields, which leads to a significant increase in the cost and assembly time of the reinforced formwork blocks. At the same time, steel fiber reinforced concrete has a high manufacturing cost, which, given the lack of the ability to join it during assembly, does not allow its use as a load-bearing element.At the same time, the presence of rod reinforcement in the formwork block increases the block's weight and increases the labor intensity of ensuring high-quality monolithic concrete placement. A disadvantage of these formwork blocks is the low rigidity of the permanent steel fiber concrete formwork, which prevents the creation of conditions for constrained deformation of the concrete within the structure as a whole.
[0007] A reinforcing formwork block with external sheet reinforcement is known from the existing level of technology (patent RU No. 231090, 09 / 25 / 2024), containing a reinforcing formwork block filled with concrete, including reinforcing cages of steel sheets of permanent formwork, ensuring a reduction or complete elimination of rod reinforcement without pre-stressing due to the inclusion of steel sheet elements used as permanent formwork, a reduction in the weight of prefabricated reinforcing formwork blocks, and a reduction in labor costs during installation.A significant disadvantage of the proposed technology is the use of thin steel sheets, which do not provide sufficient rigidity and strength when laying monolithic concrete, as well as the lack of connections between the external steel formwork sheets and the volume of concrete of the structure, which does not allow the inclusion of steel formwork sheets in the resistance to transverse deformations of concrete under compression and does not create conditions for constrained deformation under external load, as well as the low level of rigidity of the permanent steel external sheet formwork.
[0008] The closest analogue to the claimed utility model is a steel panel design (CN206928462 U dated January 26, 2018), comprising a box-section metal frame with T-shaped stiffeners arranged inside, alternately attached to opposite longitudinal sides of the frame. A disadvantage of the claimed technical solution is the insufficient load-bearing capacity of compressed and eccentrically compressed elements.
[0009] The technical problem solved by the utility model is to increase the bearing capacity of compressed and eccentrically compressed elements.
[0010] The technical result is achieved due to the fact that the reinforcement formwork block includes a metal frame in the form of two longitudinal steel sheets, joined by means of a welded joint into a box-shaped section with two transverse steel sheets, while inside the metal frame formed in this way there are stiffening ribs in the form of T-shaped elements, fixed alternately on opposite longitudinal steel sheets by means of a welded joint, the length of each stiffening rib is 2 / 3 of the width of the transverse steel sheet.
[0011] Longitudinal and transverse steel sheets can be made of C355 steel with a thickness of 20 to 40 mm.
[0012] Longitudinal steel sheets include T-shaped stiffeners spaced at a specified pitch. The stiffener spacing parameters are determined by calculations in accordance with current regulatory documents. T-shaped stiffeners can be manufactured from standard rolled I-beams, cut along the web to form perforations. This design allows both resulting T-shaped parts to be used in the stiffener construction by welding them to the longitudinal steel sheet using TZ-type welds in accordance with GOST 14771-76 (Gas-shielded arc welding). The longitudinal and transverse steel sheets are joined using U6-type welds in accordance with GOST 14771-76.
[0013] To fill the reinforced concrete block with monolithic concrete, self-compacting concrete mixtures are used in accordance with GOST R 59714-2021 (Self-compacting concrete mixtures. Technical specifications) with a design concrete compressive strength class of B60 to B150. The use of self-compacting concrete mixtures and the absence of rod reinforcement eliminates the possibility of cavities and voids, reducing labor costs for specialized quality control.
[0014] The ultra-high load-bearing capacity prefabricated structure is shown in Fig.1 and Fig.2, where:
[0015] 1 - longitudinal steel sheets;
[0016] 2 - T-shaped stiffeners;
[0017] 3 - transverse steel sheets.
[0018] The technical result of increasing the load-bearing capacity of compressed and eccentrically compressed elements, achieved by the specified utility model, is achieved through the use of stiffening ribs made of T-shaped sections, which form a longitudinal connection between adjacent steel sheets by anchoring them into the core zone of the concrete, enclosed between the flanges of the T-shaped sections. It is known that limiting transverse deformations of concrete leads to an increase in its strength and deformability, which ensures a significant increase in the load-bearing capacity of the section. This effect occurs as a result of changes in the concrete's behavior, characterized by crack formation at load levels greater than 0.4...0.8 times the failure load (dilation deformations of the concrete occur).Limiting transverse deformations through the reactive action of the steel sheets, which increases proportionally to the longitudinal load, prevents the formation and propagation of these cracks, resulting in increased ultimate strength and deformation of the concrete in the longitudinal direction of the structure. Transverse deformations are limited by anchoring the T-shaped flanges of the opposite steel sheets within the central concrete core without the use of through bracing elements.
[0019] Furthermore, the claimed utility model reduces construction time by reducing the labor intensity of manufacturing and installing building structures from reinforced formwork blocks, reducing the weight of prefabricated elements, and automating the block joining process using welding. At the same time, the spatial rigidity of the reinforced formwork blocks is maintained during installation, ensuring the reliability and load-bearing capacity of the steel-reinforced concrete structure with external sheet reinforcement, obtained after the pouring of monolithic concrete.
[0020] The intended area of implementation of the utility model is the design and construction of high-rise buildings and structures for various purposes using the precast-monolithic construction method with the use of reinforced formwork blocks of structures with ultra-high load-bearing capacity.
Claims
1. A reinforcing formwork block comprising a metal frame in the form of two longitudinal steel sheets joined by means of a welded joint in a box-shaped section with two transverse steel sheets, wherein inside the metal frame formed in this way there are stiffening ribs in the form of T-shaped elements, alternately secured to opposite longitudinal steel sheets by means of a welded joint, characterized in that the length of each stiffening rib is 2 / 3 of the width of the transverse steel sheet.
2. A reinforcement formwork block according to paragraph 1, characterized in that the longitudinal and transverse steel sheets are made of C355 steel with a thickness of 20 to 40 mm.
3. A reinforcement formwork block according to item 1, characterized in that the stiffening ribs made of T-shaped parts have perforations on the wall.