Foam concrete filled shear wall with negative Poisson's ratio structure

Abstract

The invention provides a foam concrete filled shear wall with a negative Poisson's ratio structure. The anti-seismic property, the energy dissipation capacity and the stability of the shear wall are improved. The negative Poisson's ratio structure can effectively bear large shearing force and bending moment under the action of earthquakes and wind loads, earthquake energy is absorbed in a unique deformation mode, and local damage of a traditional shear wall during the large earthquakes is avoided. The structure expands but not contracts when stretched or compressed, and ductility and energy buffering capacity are enhanced. The invention provides three negative Poisson's ratio structure unit combination modes, namely a three-dimensional tubular structure, a chiral structure and a rotating rigid body composite structure, so that different shear wall configuration and anti-seismic requirements are met. The use of the foam concrete improves the shock resistance of the wall body. The construction process of the structure is simple and convenient, the negative Poisson's ratio structure and foam concrete characteristics enable wall components to be prefabricated, the construction period is shortened, the labor intensity is reduced, and the anti-seismic function is improved.

Description

Technical field:

[0001] The invention relates to a foam concrete filled shear wall with a negative Poisson's ratio structure, and belongs to the field of new civil engineering structures and disaster prevention and reduction. Background technology:

[0002] Shear walls are a common earthquake-resistant component and structural component, usually composed of steel bars and concrete materials, used to resist the horizontal force and dynamic effects generated by earthquakes and strong winds. Setting up shear walls in buildings can significantly improve the earthquake resistance of the structure and enhance the stability of the structure. Therefore, shear walls play an important role in high-rise buildings. The high-rise building structural system with shear walls as the main lateral force resisting component mainly includes shear wall structure and frame-shear wall structure. The concept and theory of structural seismic design show that the main function of the shear wall is to serve as the first line of seismic defense of the structural system, to resist lateral loads (such as wind loads, earthquake loads, etc.) through its own stiffness and strength, and to prevent serious damage to substructures such as frames. When the shear wall is subjected to external forces, the entire wall will bend and deform, dissipate energy and reduce structural stress. Traditional shear wall design mainly relies on its stiffness and strength to resist lateral loads or horizontal effects. However, when shear walls are subjected to strong earthquakes or ultra-rare earthquakes, they may experience significant deformations beyond expectations, causing the walls to rupture or fail, which in turn affects the seismic performance of the entire structure. Under strong multi-dimensional earthquakes, the energy dissipation capacity and ductility of traditional shear walls need to be strengthened, otherwise out-of-plane damage, serious structural damage, overturning, or even collapse may occur. In addition, traditional shear walls often produce significant residual deformations after an earthquake, which are difficult to restore to their original state, resulting in low seismic toughness of the structure and the need to invest a lot of money in repairs, affecting the safety and applicability of the building structure after the earthquake. In order to further improve the seismic performance of shear walls, researchers have tried to improve the performance of shear walls by adopting various new materials and structural design ideas in recent years. For example, by adding new materials such as high-strength steel plates, high-strength concrete, high-ductility concrete, or energy dissipation devices such as dampers into shear walls, the dynamic response of the structure and seismic damage losses can be reduced. However, the above ideas and measures are relatively mature, with little room for improvement, high engineering costs, and no fundamental improvements in the shear wall force mechanism. If collaborative innovation is carried out in terms of shear wall material composition, internal structural form, and mechanical mechanism, new ideas and technologies can be provided for improving the seismic performance of shear walls. Poisson's ratio is a physical quantity that describes the relationship between the lateral strain and the longitudinal strain of a material or structure when it is deformed by force. Specifically, when a material or structure is stretched or compressed in one direction, its size in the vertical direction will change, and the ratio of this change is the Poisson's ratio. A key feature of negative Poisson's ratio materials is that they can exhibit a completely different physical response from conventional materials when subjected to external forces. When a negative Poisson's ratio material or structure is stretched, it will "expand" in the direction perpendicular to the stretching direction instead of contracting, that is, the lateral size increases and the longitudinal size also increases, which is completely opposite to the behavior of traditional materials or structures. Compared with positive Poisson's ratio structures, negative Poisson's ratio structures have the advantages of better shear resistance, fracture resistance, energy dissipation performance, and a flatter hysteresis curve. Given the unique mechanical properties and deformation capacity of negative Poisson's ratio materials, they can be used in structural components to effectively absorb and dissipate seismic energy under earthquakes, reduce the dynamic response of buildings, and improve the seismic performance of structures. In addition, the negative Poisson's ratio structure also has good self-reset ability, that is, when the external load is applied and removed, the structure can return to its original state, thereby avoiding permanent residual deformation and improving the long-term stability, recoverability and anti-collapse ability of the building. Components made of negative Poisson's ratio materials usually have a hollow form. In order to improve their stability and bearing capacity, they still need to be supplemented with other energy-consuming materials. The low-density characteristics of foam-filled concrete can effectively reduce the weight of the structure and reduce the stress of the core load-bearing components, thereby saving construction costs and improving building stability. Foam-filled concrete also has excellent thermal insulation, heat preservation, and sound insulation properties, which helps to improve energy efficiency, reduce energy consumption, and can effectively enhance earthquake resistance and delay the spread of fire. In addition, its convenient construction and low raw material cost can further reduce the overall cost of the building. At the same time, it is environmentally friendly and helps to reduce carbon emissions. Therefore, combining the advantages of negative Poisson's ratio structure and foam-filled concrete can propose a foam concrete-filled shear wall with a negative Poisson's ratio structure, which has outstanding seismic energy dissipation performance and innovation. Summary of the invention:

[0003] The foamed concrete filled shear wall with negative Poisson's ratio structure proposed in the present invention combines a variety of new negative Poisson's ratio structures with foamed concrete materials, which can effectively improve the seismic performance and energy dissipation capacity of the shear wall and improve the stability and anti-collapse performance of the structure. The introduction of negative Poisson's ratio structure enables shear walls to not only withstand large shear forces and bending moments under earthquakes and strong wind loads, but also effectively absorb earthquake energy through its special deformation mode during the application of dynamic forces, thus avoiding the problem of local damage or serious deformation of traditional shear walls during large earthquakes. In particular, when the negative Poisson's ratio structure is stretched or compressed, it can expand in the expected direction instead of contracting, achieving energy dispersion and buffering, and enhancing the energy dissipation capacity and ductility of the structure. In order to further improve the efficiency of the negative Poisson's ratio structure, the present invention also proposes a combination of multiple negative Poisson's ratio structural units. Specifically, the structure mainly includes three forms: three-dimensional tubular structure, chiral structure and rotational rigid body composite structure. Each structural form has unique advantages. For different shear wall configurations and structural parts, the appropriate structural form and layout can be selected according to the specific seismic requirements of the building. For example, in a high-rise building, the lower floor can use a rotational rigid body composite structure to increase the rigidity, the middle floor uses a chiral structure, and the high floor uses a lightweight three-dimensional tubular structure to enhance the overall energy consumption capacity. The above-mentioned negative Poisson's ratio structure, by virtue of its special deformation mode, can achieve excellent self-resetting performance when the shear wall is subjected to force, ensuring that the building can return to its original state after the action of the earthquake load, avoiding permanent deformation, and improving the long-term stability of the building. The rotating rigid body composite structure proposed in the present invention includes a square steel tube and steel plate composite negative Poisson's ratio structure and a triangular steel tube and steel plate composite negative Poisson's ratio structure. The structure combines rigidity requirements and deformable elements and has a good negative Poisson's ratio effect. When subjected to external force, the structure can produce local rotational deformation, making its overall deformation behavior more flexible, thereby enhancing the seismic resistance of the structure. The design of the rotating rigid body composite structure has strong adaptability and flexibility, can cope with complex load conditions, and is particularly suitable for the seismic design of high-rise buildings. The chiral structure proposed in the present invention includes a positive tetrachirality negative Poisson's ratio structure and an anti-tetrachirality negative Poisson's ratio structure, which is a negative Poisson's ratio structure with special geometric symmetry and deformation ability. It is composed of a centrally rotated rigid body and a plurality of deformable ribs, and has the characteristic that it cannot be overlapped with its mirror image through translation or rotation. The chiral structure can achieve nonlinear deformation through its asymmetric geometric form, and can effectively disperse and dissipate energy during an earthquake, thereby reducing the dynamic response of the building structure system. The advantage of the chiral structure is that it can quickly restore its original shape after an earthquake, and has good self-reset ability and strong earthquake resistance. The three-dimensional tubular structure proposed by the present invention includes a rhombus-shaped overlapping three-dimensional curved tube negative Poisson's ratio structure and a trapezoidal overlapping three-dimensional curved tube negative Poisson's ratio structure, and its geometric shape can show a significant negative Poisson's ratio effect when subjected to external force. The internal channel of the structure is grid-shaped, which can provide efficient energy absorption and dispersion capabilities under the action of external force, thereby effectively reducing the transmission of seismic loads and reducing the vibration response of the building. At the same time, the three-dimensional tubular structure has moderate stiffness, ensuring that the deformation capacity of the structure in an earthquake is greatly enhanced, and has strong shear and fracture resistance. The foam concrete filled shear wall of the present invention adopts high-performance foam concrete filling materials, which further improves the seismic resistance and stability of the wall. Foam concrete not only has a lower density, effectively reducing the weight of the wall, but also has a good energy absorption capacity, can fully deform and consume energy during an earthquake, and reduce the effective stress of the shear wall and the structural system. In addition, according to different seismic design requirements, the filling rate of foam concrete can be reasonably configured to achieve the best balance between wall stiffness, strength and energy consumption performance. During the implementation process, the construction of foam concrete filled shear walls is also relatively simple. Due to the negative Poisson's ratio structure and the characteristics of foam concrete, the wall components and construction process can be optimized and prefabricated, thereby reducing the construction period and labor intensity. Through precise structural design and efficient construction technology, the comprehensive benefits and earthquake resistance of the building can be significantly improved. In summary, the shear wall of the present invention combines a negative Poisson's ratio structure with a foam concrete material to give full play to the advantages of both. The introduction of a negative Poisson's ratio structure can not only improve the seismic performance of the shear wall, but also improve the deformation behavior of the wall under earthquake action, so that the structure exhibits stronger stability and seismic toughness under extreme environments. In addition, the filling of foam concrete can effectively reduce the weight of the wall, reduce the overall load of the building, and improve the seismic efficiency of the structure. This new type of shear wall has excellent seismic performance, significant energy dissipation capacity and good self-reset ability. It can greatly reduce structural damage in earthquake disasters and improve the seismic reliability of buildings. This patent adopts the following technical solutions: A foamed concrete filled shear wall with a negative Poisson's ratio structure, the shear wall comprising: a shear wall panel (1), a negative Poisson's ratio structure (2), a pre-buried connection piece (3), foamed concrete (4), a square steel pipe (5), a connection steel plate (6), a square steel pipe and steel plate composite negative Poisson's ratio structure (7), a triangular steel pipe (8), a triangular steel pipe and steel plate composite negative Poisson's ratio structure (9), a circular steel pipe (10), a positive four-chirality negative Poisson's ratio structure (11), an anti-four-chirality negative Poisson's ratio structure (12), a circular curved pipe (13), a rhombus-shaped overlapping three-dimensional curved pipe negative Poisson's ratio structure (14), and a trapezoidal overlapping three-dimensional curved pipe negative Poisson's ratio structure (15). The foamed concrete filled shear wall body of the negative Poisson's ratio structure comprises a shear wall panel (1), a negative Poisson's ratio structure (2), a pre-embedded connector (3) and foamed concrete (4). First, the negative Poisson's ratio structure (2) is prefabricated in a factory, and after the specific negative Poisson's ratio structure (2) and the shear wall panel (1) are assembled, the foamed concrete (4) is poured into a steel pipe, and then the pre-embedded connector (3) is configured. The top and bottom of the shear wall are fixed to the building frame beam by bolts through the pre-embedded connector (3), and the installation is carried out from bottom to top, and the bolts and connection parts should be treated with anti-corrosion. The shear wall panel (1) can be a lightweight partition wall such as an autoclaved aerated concrete partition wall, a high-strength ceramsite partition wall or a glass fiber reinforced cement partition wall, with a compressive strength of not less than 10 MPa, a thermal conductivity of not more than 0.2 W / m·K, a fire rating of A1, good water resistance, and a single-layer wall panel thickness of 30 mm to 50 mm. The specific negative Poisson's ratio structures include a rotational rigid body composite structure, a chiral structure and a three-dimensional tubular stacked structure. The rotating rigid body composite structure comprises a square steel tube and steel plate composite negative Poisson's ratio structure (7) and a triangular steel tube and steel plate composite negative Poisson's ratio structure (9). The square steel tube and steel plate composite negative Poisson's ratio structure (7) is a structure obtained by connecting a square steel tube (5) with a connecting steel plate (6) after rotation, and foam concrete grouting is performed in the square steel tube. The triangular steel tube and steel plate composite negative Poisson's ratio structure (9) is a structure obtained by connecting a triangular steel tube (10) with a connecting steel plate (6) after rotation, and foam concrete (4) is grouting in the triangular steel tube. The square steel tube (5) and the triangular steel tube (10) are made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 80mm to 120mm, and a wall thickness of not less than 5mm. The wall thickness of the connecting steel plate (6) is not less than 5mm, the square steel tube (5) rotates at an angle of 45°, and a honeycomb grid is formed by welding the connecting steel plates. The triangular steel pipe (10) is rotated at an angle of 60° to form a regular triangular grid. The inner wall of the steel pipe needs to be sandblasted before grouting to ensure that the bonding strength with the foam concrete (4) is not less than 1.2 MPa. The chiral structure comprises a positive tetrachirality negative Poisson's ratio structure (11) and an anti-tetrachirality negative Poisson's ratio structure (12). The circular steel pipe (10) is connected by a connecting steel plate (6) in the form of a positive tetrachirality structure and an anti-tetrachirality structure, and foam concrete (4) is grouted in the circular steel pipe. The circular steel pipe (10) is made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 60mm to 80mm, and a wall thickness of not less than 3mm. The wall thickness of the connecting steel plate (6) is not less than 3mm, and laser cutting is used to ensure geometric accuracy. The chiral node spacing is 100mm to 150mm, and the positive tetrachirality negative Poisson's ratio structure (11) connecting steel plate (6) is rotated 45° clockwise to form a four-arm spiral symmetrical structure. The anti-tetrachirality negative Poisson's ratio structure (12) connecting steel plate (6) is arranged by rotating 45° counterclockwise. The three-dimensional tubular superposition structure comprises a rhombus-shaped superposition three-dimensional curved tube negative Poisson's ratio structure (14) and a trapezoid-shaped superposition three-dimensional curved tube negative Poisson's ratio structure (15). The rhombus-shaped superposition three-dimensional curved tube negative Poisson's ratio structure (14) is made by combining a circular curved tube (13) and a circular steel tube (10) into a rhombus structure and then superimposing them into a three-dimensional structure. The trapezoid-shaped superposition three-dimensional curved tube negative Poisson's ratio structure (15) is made by superimposing circular steel tubes (10) into a three-dimensional structure after being spliced ​​according to a trapezoidal grid. In the rhombus-shaped superposition three-dimensional curved tube negative Poisson's ratio structure (14), the circular curved tube is made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 20mm to 30mm, a wall thickness of not less than 2mm, and a curvature radius of 100mm to 120mm. The side length of the diamond grid is 160mm to 200mm, the spacing between the overlapping layers is 100mm to 150mm, and the overall structure height matches the shear wall panel (1). The circular steel pipe (10) in the trapezoidal overlapping three-dimensional curved tube negative Poisson's ratio structure (15) is made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 40mm to 60mm, and a wall thickness of not less than 3mm. The upper bottom of the trapezoidal grid is 120mm to 160mm, the lower bottom is 180mm to 220mm, the height is 80mm to 120mm, the spacing between the overlapping layers is 100mm to 120mm, and the overall structure height matches the shear wall panel (1). The foamed concrete (4) has a density in the range of 400 kg / m 3 ~1000kg / m 3 The specific selection needs to be adjusted according to the structural requirements. 400kg / m 3 ~600kg / m 3 Low-density foam concrete, 800kg / m 3 ~1000kg / m 3The high-density foam concrete has a compressive strength of not less than 10MPa and an elastic modulus of not less than 342MPa. It is recommended that the Poisson's ratio be designed to be a negative value, and the negative Poisson's ratio effect be achieved with the help of pore structure optimization. The embedded connector (3) is made of high-strength carbon steel, the bolt specification is M20, the tensile strength is not less than 400MPa, the spacing is not more than 500mm, the embedded depth is not less than 200mm, the installation position deviation of the negative Poisson's ratio structure (2) should not exceed 5mm, and the verticality deviation should not exceed 1 / 500. Compared with the prior art, the advantages of the present invention are as follows: 1. The comprehensive shear resistance and energy dissipation capacity are better. Traditional shear walls rely on stiffness and strength to resist lateral loads, but are prone to shear deformation and rupture during large earthquakes and have weak energy dissipation capacity. The present invention introduces negative Poisson's ratio structures (such as three-dimensional tubular, chiral, and rotational rigid body composite structures) and utilizes their unique deformation characteristics to expand laterally rather than contract when subjected to force, thereby effectively dispersing seismic energy and improving energy dissipation efficiency. For example, the grid-like channels of the three-dimensional tubular structure can reduce vibration transmission, the nonlinear deformation of the chiral structure can quickly dissipate energy, and the rotational rigid body composite structure improves toughness through local rotational deformation. This design makes the wall's shear resistance, fracture resistance, and energy absorption capacity significantly better than traditional structures. 2. Improved self-reset capability and stronger long-term stability. Traditional shear walls often suffer permanent damage after an earthquake because plastic deformation is difficult to recover. The negative Poisson's ratio structure of the present invention can restore its original state through its geometric characteristics after the earthquake load is removed, reducing residual deformation, thereby avoiding damage to the building function and improving long-term stability. For example, the asymmetric geometric design of the chiral structure enables it to have rapid shape recovery capabilities. 3. Easy to achieve lightweight structure and optimize material performance. The low density of foam concrete reduces the deadweight of the wall and the load on the foundation and support system. At the same time, its excellent energy dissipation characteristics can disperse seismic energy. Compared with traditional reinforced concrete shear walls, the filling ratio of foam concrete can be flexibly adjusted to achieve the best balance of stiffness, strength and energy consumption. In addition, the sound insulation and heat insulation properties of foam concrete also improve the energy efficiency of the building. 4. The structure is customizable and flexible. By combining different negative Poisson's ratio structural units (such as three-dimensional tubular units for low-rise building energy dissipation and rotating rigid composite units for high-rise building stiffness reinforcement), the design can be optimized for different building types and seismic requirements. 5. Convenient construction and high economy. Foam concrete is easy to construct and has low raw material costs. Combined with the modular design of the negative Poisson's ratio structure, it can reduce the construction period and labor costs, further reduce the complexity of construction, and reduce the total cost of the building. 6. The overall durability of the structure is high and it is easy to repair. The damage of traditional shear walls is mostly concentrated in the bottom plastic hinge area, which is difficult to repair. However, the negative Poisson's ratio structure of the present invention reduces the risk of local damage by dispersing stress and dissipating energy evenly, improves overall durability and is easy to repair. Description of the drawings: Figure 1 Schematic diagram of a foam concrete filled shear wall with a negative Poisson's ratio structure according to the present invention Figure 2 Schematic diagram of foam concrete filling for a foam concrete-filled shear wall with a negative Poisson's ratio structure Figure 3 Schematic diagram of the cross section of a square steel tube and steel plate composite negative Poisson's ratio structure Figure 4 Schematic diagram of the assembly of a square steel tube and steel plate composite negative Poisson's ratio structure Figure 5 Schematic diagram of the cross section of a triangular steel tube and steel plate composite negative Poisson's ratio structure Figure 6 Schematic diagram of the assembly of the triangular steel tube and steel plate composite negative Poisson's ratio structure Figure 7 Schematic diagram of the cross section of the positive quadrilateral negative Poisson's ratio structure Figure 8 Schematic diagram of the assembly of a positive quadruple chiral negative Poisson's ratio structure Fig. 9 Schematic diagram of the cross section of the anti-quadrichiral negative Poisson's ratio structure Fig.10 Schematic diagram of the assembly of the anti-quadruple-chiral negative Poisson's ratio structure Fig.11 Schematic diagram of the negative Poisson's ratio structure of a rhombus-shaped folded three-dimensional elbow Fig.12 Schematic diagram of combined pipe bending Fig.13 Schematic diagram of the assembly of the rhombus-shaped 3D curved tube with negative Poisson's ratio Fig.14 Schematic diagram of the negative Poisson's ratio structure of a trapezoidal laminated three-dimensional elbow Fig.15 Schematic diagram of the assembly of the trapezoidal stacked three-dimensional curved tube with negative Poisson's ratio Fig.16 Example of the plan layout of the frame-shear wall structure system Fig.17 Schematic diagram of a single-layer frame-shear wall structure system Specific implementation method: The following is combined with Figure 1-17 The present invention is described in detail with reference to the accompanying drawings and embodiments to better understand the structural and functional characteristics of the present invention. The purpose, structure and innovation of the present invention can be better understood based on the following examples, but it should be pointed out that the examples are only used to illustrate the present invention, rather than to limit the implementation mode of the present invention. Ordinary researchers in this field can still make other beneficial changes based on the above description. Example 1 The present embodiment provides a foamed concrete filled shear wall with a negative Poisson's ratio structure, which mainly includes: 1-shear wall panel, 2-negative Poisson's ratio structure, 3-embedded connector, 4-foamed concrete, 5-square steel pipe, 6-connecting steel plate, 7-square steel pipe and steel plate composite negative Poisson's ratio structure, 8-triangular steel pipe, 9-triangular steel pipe and steel plate composite negative Poisson's ratio structure, 10-circular steel pipe, 11-positive four-chirality negative Poisson's ratio structure, 12-anti-four-chirality negative Poisson's ratio structure, 13-circular bent pipe, 14-rhombus-shaped overlapping three-dimensional bent pipe negative Poisson's ratio structure, 15-trapezoidal overlapping three-dimensional bent pipe negative Poisson's ratio structure. This implementation example takes a 20-story high-rise frame-shear wall structure as an example, adopts a rotating rigid body composite structure as the core unit of the negative Poisson's ratio structure, and combines it with low-density foam concrete filling. The specific design is as follows: The implementation steps are as follows: 1) Structural design and selection of negative Poisson's ratio structure First, the selection and design of negative Poisson's ratio structure are determined according to the actual needs of the building structure. According to the seismic and shear requirements of the building, the structural design takes into account the load conditions of each floor and the reasonable layout of the shear walls. Specifically, the shear walls are distributed in the main load-bearing positions of the building to ensure the seismic performance and stability of the building. 2) For a 20-story high-rise building, the frame-shear wall structure with a floor height of 3.6m, the plane size is 60m×24m, and the size of the bottom frame column is 800mm×800mm. The design intensity is 8 degrees, and the site is Class II. The shear wall thickness is designed to be 300mm, and the shear wall is continuous throughout the entire floor height. The outer shear wall is arranged along the long side of the building, with a length of 3.0m, symmetrically distributed to balance the lateral stiffness, and the plane layout is as follows Fig.16 As shown, the single-layer structure is Fig.17 The 20-story shear walls are divided into three groups: 1-7 floors are equipped with square steel tube and steel plate composite negative Poisson's ratio structural shear walls, 8-14 floors are equipped with anti-quadrichiral negative Poisson's ratio structural shear walls, and 15-20 floors are equipped with diamond-shaped superimposed three-dimensional curved tube negative Poisson's ratio structural shear walls. 3) The square steel tube in the shear wall of the square steel tube and steel plate composite negative Poisson's ratio structure is made of Q345 steel with an outer diameter of 100mm and a wall thickness of 5mm. The connecting steel plate is 5mm thick and is welded by TIG (non-melting inert gas shielded arc welding). The weld meets the requirements of the first-level weld in the Code for Welding of Steel Structures GB 50661-2011. The square steel tube is rotated at an angle of 45° and welded by connecting steel plates to form a honeycomb grid. The circular steel tube in the anti-quadrichiral negative Poisson's ratio structure shear wall is made of Q345 steel with an outer diameter of 80mm and a wall thickness of 3mm. The connecting steel plate is 3mm thick and laser cutting is used to ensure geometric accuracy. The chiral node spacing is 150mm, and the connecting steel plates are arranged in a counterclockwise rotation of 45°. The circular bend in the rhombus-shaped superimposed three-dimensional bend negative Poisson's ratio structure shear wall is made of Q345 steel with an outer diameter of 30mm, a wall thickness of 3mm, and a curvature radius of 150mm. The diamond grid has a side length of 200mm and a stacking layer spacing of 150mm. The nodes of the three-dimensional tubular stacked structure are welded by TIG welding, and the welds meet the requirements of the first-level welds in the Code for Welding of Steel Structures GB 50661-2011. 4) The negative Poisson's ratio structure is prefabricated in the factory. The rotating rigid body unit is welded with polygonal steel pipes and steel plates. The steel pipes are quadrilateral steel pipes with an outer diameter of 200mm and a wall thickness of 5mm. The thickness of the connecting steel plate is 5mm. The steel material is Q345 steel with a yield strength of 345MPa. The steel pipes and steel plates of the rotating rigid body unit are welded with TIG technology to ensure the strength and rigidity of the welded parts. 5) Then install the shear wall formwork and fix the structural unit. The steel formwork is used for the installation of the shear wall formwork. The thickness of the formwork is designed to be 30mm, which can provide sufficient strength and rigidity to withstand the pouring and weight of the foam concrete during the construction process. After the formwork is installed, fix the prefabricated rotating rigid unit in the formwork. 4) After the formwork is fixed, start pouring the foam concrete in layers, with each layer thickness controlled within 1m. Use a vibrator to compact the foam concrete to ensure its uniformity and density, and reduce the appearance of bubbles and uneven areas. The density of the concrete is determined according to the design requirements, usually 600kg / m 3 ~800kg / m 3 , to ensure its light weight and thermal insulation properties. After pouring, the shear wall is covered with a moisturizing membrane for 28 days of curing. During the curing process, the temperature is controlled at 20±5℃ and the humidity is maintained at ≥90% to ensure the strength and stability of the foam concrete. 5) After the pouring and curing of the foam concrete, the connection between the shear wall and the main frame structure begins. The top of the shear wall is fixed to the building frame beam with bolts through the preset connector. The bolt specification is M20, and the bolt spacing does not exceed 0.5m to ensure the effective combination of the shear wall and the foundation, so that the load can be stably transferred to the foundation. The above is a typical embodiment of the present invention, but the implementation of the present invention is not limited thereto.

Claims

1. A foamed concrete filled shear wall with a negative Poisson's ratio structure, the shear wall comprising: Shear wall panels, negative Poisson's ratio structures, embedded connectors, foamed concrete, square steel pipes, connecting steel plates, square steel pipe and steel plate composite negative Poisson's ratio structures, triangular steel pipes, triangular steel pipe and steel plate composite negative Poisson's ratio structures, circular steel pipes, positive four-chirality negative Poisson's ratio structures, negative four-chirality negative Poisson's ratio structures, circular bends, rhombus-shaped overlapping three-dimensional bends with negative Poisson's ratio structures, and trapezoidal overlapping three-dimensional bends with negative Poisson's ratio structures.

2. According to claim 1, the foamed concrete filled shear wall of the negative Poisson's ratio structure comprises a shear wall panel, a negative Poisson's ratio structure, embedded connectors and foamed concrete. First, the negative Poisson's ratio structure is prefabricated in a factory, and the specific negative Poisson's ratio structure is assembled with the shear wall panel, and then the foamed concrete is poured into the steel pipe, and then the embedded connectors are configured. The top and bottom of the shear wall are fixed to the building frame beam by bolts through the embedded connectors, and the installation is carried out from bottom to top, and the bolts and connection parts should be treated with anti-corrosion.

3. According to claim 1, the shear wall panel can be a lightweight partition wall such as an autoclaved aerated concrete partition wall, a high-strength ceramsite partition wall or a glass fiber reinforced cement partition wall, with a compressive strength of not less than 10Mpa, a thermal conductivity of not more than 0.2W / m·K, a fire rating of A1, good water resistance, and a single-layer wall panel thickness of 30mm to 50mm.

4. The specific negative Poisson's ratio structure according to claim 1 comprises a rotational rigid body composite structure, a chiral structure and a three-dimensional tubular stacked structure.

5. According to claim 3, the rotating rigid body composite structure comprises a square steel tube and steel plate composite negative Poisson's ratio structure and a triangular steel tube and steel plate composite negative Poisson's ratio structure. The square steel tube and steel plate composite negative Poisson's ratio structure is a structure obtained by connecting the square steel tube by the connecting steel plate after the square steel tube is rotated, and foam concrete grouting is performed in the square steel tube. The triangular steel tube and steel plate composite negative Poisson's ratio structure is a structure obtained by connecting the triangular steel tube by the connecting steel plate after the triangular steel tube is rotated, and foam concrete grouting is performed in the triangular steel tube. The square steel tube and the triangular steel tube are made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 80mm to 120mm, and a wall thickness of not less than 5mm. The wall thickness of the connecting steel plate is not less than 5mm, the square steel tube rotates at an angle of 45°, and a honeycomb grid is formed by welding the connecting steel plate. The triangular steel tube rotates at an angle of 60° to form a regular triangle grid. Before grouting, the inner wall of the steel tube needs to be sandblasted to ensure that the bonding strength with the foam concrete is not less than 1.2MPa.

6. According to claim 3, the chiral structure comprises a positive tetrachirality negative Poisson's ratio structure and an anti-tetrachirality negative Poisson's ratio structure. The circular steel pipe is connected by a connecting steel plate in the form of a positive tetrachirality structure and an anti-tetrachirality structure, and foam concrete grouting is performed in the circular steel pipe. The circular steel pipe is made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 60mm to 80mm, and a wall thickness of not less than 3mm. The wall thickness of the connecting steel plate is not less than 3mm, and laser cutting is used to ensure geometric accuracy. The chiral node spacing is 100mm to 150mm, and the positive tetrachirality negative Poisson's ratio structure connecting steel plate is rotated 45° clockwise to form a four-arm spiral symmetrical structure. The anti-tetrachirality negative Poisson's ratio structure connecting steel plates are arranged by rotating 45° counterclockwise.

7. According to claim 3, the three-dimensional tubular superimposed structure comprises a rhombus-shaped superimposed three-dimensional curved tube negative Poisson's ratio structure and a trapezoidal-shaped superimposed three-dimensional curved tube negative Poisson's ratio structure. The rhombus-shaped superimposed three-dimensional curved tube negative Poisson's ratio structure is made by combining a circular curved tube and a circular steel tube into a rhombus structure and then superimposing them into a three-dimensional structure. The trapezoidal-shaped superimposed three-dimensional curved tube negative Poisson's ratio structure is made by superimposing circular steel tubes into a three-dimensional structure after being spliced ​​according to a trapezoidal grid. In the rhombus-shaped superimposed three-dimensional curved tube negative Poisson's ratio structure, the circular curved tube is made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 20mm to 30mm, a wall thickness of not less than 2mm, and a curvature radius of 100mm to 120mm. The side length of the rhombus grid is 160mm to 200mm, the spacing between the superimposed layers is 100mm to 150mm, and the overall structure height matches the shear wall panel. The circular steel pipe in the trapezoidal laminated three-dimensional curved tube negative Poisson's ratio structure is made of high-strength carbon steel, with a yield strength of not less than 345MPa, a tensile strength of not less than 490MPa, an outer diameter of 40mm to 60mm, and a wall thickness of not less than 3mm. The upper base of the trapezoidal grid is 120mm to 160mm, the lower base is 180mm to 220mm, the height is 80mm to 120mm, the spacing between the laminated layers is 100mm to 120mm, and the overall structure height matches the shear wall panel.

8. The foamed concrete according to claim 1 has a density in the range of 400 kg / m 3 ~1000kg / m 3 The specific selection needs to be adjusted according to the structural requirements. 400kg / m 3 ~600kg / m 3 Low-density foam concrete, 800kg / m 3 ~1000kg / m 3 The high-density foam concrete has a compressive strength of not less than 10MPa and an elastic modulus of not less than 342MPa. It is recommended that the Poisson's ratio be designed to be a negative value, and the negative Poisson's ratio effect be achieved with the help of pore structure optimization.

9. According to claim 1, the embedded connector is made of high-strength carbon steel, the bolt specification is M20, the tensile strength is not less than 400MPa, and the spacing is not more than 500mm. The embedded depth is not less than 200mm, the installation position deviation of the negative Poisson's ratio structure should not exceed 5mm, and the verticality deviation should not exceed 1 / 500.

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