Simplified modeling and optimal design method for transverse connection nodes of modular building

Abstract

The invention belongs to the technical field of modular buildings, and particularly relates to a simplified modeling and optimal design method for a transverse connection node of a modular building. Comprising the steps that 1, parameters of a test piece are obtained, modeling is conducted through a layered shell unit, key calculation data are obtained, and a constitutive relation of a double-node unit is constructed; step 2, establishing an elastic-plastic finite element model of the high-rise modular shear wall structure; 3, carrying out elastic-plastic analysis on the model, recording structural response, and calculating damage parameters; and 4, judging whether to adjust the component design parameters or not according to the damage parameter limit value. According to the method, a double-node unit constitutive structure of bending / shearing behaviors is constructed through layered shell simulation data, a damage evaluation model under multistage earthquakes is established, the reinforcement ratio and the post-cast section width are optimized based on the damage overrun degree, and a closed loop of the construction model, structural analysis, damage evaluation and parameter optimization is formed. And a design platform with adjustable and controllable anti-disaster performance is provided for the high-rise modular building.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of modular construction, and particularly relates to a simplified modeling and optimized design method of a transverse connecting node of a modular building. BACKGROUND

[0002] At present, the construction industry is facing several challenges, such as labor shortage caused by population aging, and serious environmental pollution caused by traditional construction sites. Modular construction is the integration of a large number of prefabricated modules, which can be pre-assembled off-site, thereby alleviating the problems of labor and pollution. At the same time, due to the development of urban densification, modular construction is increasingly applied to high-rise buildings.

[0003] In recent years, the seismic performance of high-rise modular buildings has attracted more and more attention, and the research on the seismic performance mainly relies on numerical simulation. The simulation of the connection between modules is the focus when performing numerical simulation of modular buildings. The simplest way is to regard the modular structure as a cast-in-place building, but the joint between the modules of the modular building is prone to semi-rigidity, and the simulation result has a large error. The generalized modulus reduction method is a relatively convenient method for considering the connection between modules, but it cannot obtain the stress-strain state of the connection. Using spring elements to simulate the stress-strain state of the connection between modules is more direct, and the parameters of the connection spring can be defined by simply calculating the joint data obtained through the experiment in the early stage. SUMMARY

[0004] The application discloses a simplified modeling and optimized design method of a transverse connecting node of a modular building, a double-node element constitutive relation of bending / shear behavior is constructed through layered shell simulation data, a damage evaluation model under multi-level earthquakes is established, and the reinforcement ratio and post-pouring section width are optimized based on the damage overrun degree, thereby forming a closed loop of "constitutive modeling, structure analysis, damage evaluation, and parameter optimization", and providing a design platform with adjustable and controllable disaster resistance performance for high-rise modular buildings.

[0005] To achieve the above-mentioned purpose, the technical scheme of the application is as follows: A simplified modeling and optimized design method of a transverse connecting node of a modular building, comprising the following steps: Step 1. Obtain the parameters of the test specimen, model using the layered shell element of the finite element software OpenSees, obtain key calculation data, and construct the constitutive relation of the double-node element; Step 2. Establish an elastoplastic finite element model of a high-rise modular shear wall structure; Step 3. Perform elastoplastic analysis on the model, record the structure response, and calculate the damage parameter; Step 4. Determine whether to adjust the component design parameters according to the damage parameter limit value.

[0006] Preferably, in step 1: the load-mid-span deflection curve and load-slippage curve and component deformation data are obtained by simulating the transverse connection node anti-bending anti-shear test, and the axial spring and shear spring constitutive relationship of the post-cast section are established, and the specific steps are as follows: Step 1.1: Component information acquisition: including (1) bending test piece information: post-cast section width, reinforcement ratio, plate total length, plate thickness, post-cast section connection height; (2) shear test piece information: reinforcement ratio of test piece, test piece thickness, test piece width; Step 1.2: Shell element modeling to obtain post-cast section deformation data: using OpenSees software for modeling, using layered shell element to model standard bending and shear components, simulating floor connection node bending test to obtain bending component load-deflection curve and compression deformation of upper part and tensile deformation of lower part of post-cast section, simulating floor connection node shear test shear component load-slippage curve, extracting feature points of two curves, i.e. yield point, strengthening point and failure point; Step 1.3: Component bending mechanical balance analysis: simplify the original shell element bending model, divide the shell element bending floor model into two rigid rectangles from the middle, and simplify the stress analysis of a part. The left part of the rigid rectangle is subjected to the support reaction force at the left lower corner, the test loading force at a distance of 2 / 3 of the length of the rigid body from the left upper corner of the rigid body, the horizontal pressure F1 at the right upper corner of the rectangular rigid body, and the horizontal tension F2 at the right lower corner of the rectangular rigid body. The simplified mechanical balance equation in the bending test state of the component is established, and the stress conditions of the post-cast section compression zone and tension zone are analyzed: ; ; ; ; ; ; In the above formula, y 挠度 is the deflection in the stress direction of the middle part of the shell element bending model, L is the length of the rectangular rigid body, L2 is the width of the rectangular rigid body, and L1=2 / 3L; The yield point, strengthening point and failure point parameters of the simulated load-deflection curve are substituted into the formulas for calculating F1 and F2 in the simplified mechanical balance equation in the bending test state of the component: and ; The compression force F1 and the tensile force F2 of the corresponding double-node element are calculated, the three-linear hysteretic constitutive relationship of the double-node axial is fitted combined with the post-cast section deformation data, and is used to simulate the bending behavior under seismic action; Step 1.4: Component shear mechanics balance analysis: The mechanical model of the shell element shear component is simplified to three rigid rectangular, the middle rigid rectangular is connected to the left and right rigid rectangular, the middle rigid rectangular is subjected to four shear forces, which come from the shear forces of the bottom of the middle rigid rectangular and the two side rigid rectangular and the shear forces of the top of the two side rigid rectangular and the middle rigid rectangular; the simplified mechanical formula F = P / 4 is established under the shear test state of the component, P is the load of the shear test, F is the load of the shear constitutive relationship at the characteristic point of the load-slip curve to be calculated, the yield point, the strengthening point and the failure point parameters of the simulated load-slip curve are substituted into the simplified mechanical formula F = P / 4 under the shear test state of the component, and the shear force F at the characteristic point is calculated; the slip of the constitutive relationship characteristic point is equal to the slip amount of the characteristic of the simulated load-slip curve, and the size of the load is the same as F, so that the constitutive curve in the double-node shear direction is obtained; Step 1.5: Constitutive construction: The modular building transverse connection node is simulated by using a double-node unit, and a hysteretic material is used to define the mechanical properties of the local x-axis and the local y-axis of the double-node unit, that is, the bending and shear capacity of the floor connection node.

[0007] Preferably, the step 2 comprises the following specific steps: Step 2.1: Shear wall unit: The shear wall is simulated by using a displacement-based beam-column unit, the cross section of which is defined by concrete fibers concrete 02 and steel fibers steel 02, and an elastic beam-column unit with an elastic modulus amplified by 1000 times is used to construct a rigid arm to simulate the length of the shear wall cross section and connect with the coupling beam; Step 2.2: Coupling beam unit: The coupling beam is simulated by using the same displacement-based beam-column unit as the shear wall; Step 2.3: Double-node unit: The twoNodeLink unit is used to simulate the mechanical properties of the floor joint, and the corner parts of adjacent modules are connected by using this unit; Step 2.4: According to the following formula: The bending capacity is converted according to the connection length of the module, and the conversion formula is: ; The shear capacity is converted according to the shear area of the module, and the conversion formula is: ; The data of the standard specimen of the double-node unit constitutive established in step 1.5 is converted.

[0008] Preferably, the step 3 comprises the following specific steps: Step 3.1, selecting an earthquake wave: selecting a 4-level earthquake intensity: frequently occurring earthquake, fortification earthquake, rare earthquake, and extremely rare earthquake; performing an elastoplastic time history analysis on the model; Step 3.2, record the displacement of each point of the structure to calculate the interlayer displacement angle; record the relative displacement of the x-axis and y-axis of the double-node element in the local coordinate system to obtain the compression deformation, tensile deformation and shear slip of the double-node element to calculate the bending damage parameter and shear damage parameter; Step 3.3, calculate the bending damage parameter and shear damage parameter according to the formula respectively; Shear damage parameter calculation formula: , wherein δ s is the maximum relative slip in the time history analysis, δ u is the ultimate slip of the specimen at failure obtained by experiment or simulation; Bending damage parameter calculation formula: , wherein θ s is the maximum bending deflection in the time history analysis, θ u is the ultimate bending deflection of the specimen at failure obtained by experiment or simulation; according to the formula in step 1.3: , according to , calculate .

[0009] Preferably, the step 4 comprises the following specific steps: Step 4.1: check whether the component meets the seismic resistance requirements of the component under 4 seismic intensities, specifically: Under frequent earthquakes, D s and D b should not exceed 0.08; under fortification earthquakes, D s and D b should not exceed 0.3; under rare earthquakes, D s and D b should not exceed 0.6; under extremely rare earthquakes, D s and D b should not exceed 0.8; Step 4.2: if the shear or bending damage parameter exceeds the limit value, the basic parameters of the component, i.e. the reinforcement ratio and the width of the post-cast section, should be adjusted, and the adjustment formula is as follows: ; ; are the shear damage parameter adjustment coefficient and the bending damage parameter adjustment coefficient respectively; Through the above formula, the modified values of the new reinforcement ratio and the post-cast section connection width are obtained, and the basic information of the component is changed at this time; Step 4.3: restart from step 1.2, based on the layered shell modeling of the test piece, obtain the key point data, derive the axial / shear spring force through the mechanical equilibrium equation, construct the hysteretic constitutive for the double-node element, establish the overall structure model (including the double-node connection), perform the elastic-plastic analysis, calculate the damage parameter, and judge whether the seismic demand is met; Step 4.4: when the demand is met, output the recommended component parameters.

[0010] The beneficial effects of the method for simplified modeling and optimal design of a modular building transverse connection node are as follows: 1. Compared with the generalized modulus reduction method, the double-node element used in the present application can better output the deformation and stress of the connection node.

[0011] 2. The deformation of the connection node is ingeniously decoupled into bending and shear, and the bending of the connection node is decoupled into tension at one end and compression at the other end, and the mechanical constitutive of the connection node is calculated through mechanical analysis.

[0012] 3. The present application derives a fitting formula for the damage parameter and the reinforcement ratio and post-pouring section width of the connection node, so that after the elastic-plastic analysis, the structure optimization design can be realized according to the damage result through iterative design. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 : Flow chart of the method of the present application.

[0014] Figure 2 : Shell element load-deflection curve and shell element load-slippage curve diagram.

[0015] Figure 3 : Simplified stress analysis diagram of a bending member.

[0016] Figure 4 : Simplified stress analysis diagram of a shear member.

[0017] Figure 5 : Flow chart of the establishment of the elastic-plastic analysis model.

[0018] Figure 6 : Axial spring constitutive relationship and shear spring constitutive relationship diagram in Example 6. DETAILED DESCRIPTION

[0019] The following description is only a preferred embodiment of the present application and is not intended to limit the protection scope of the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0020] The following embodiments can be understood as part of the separate expression of the partial structure or method of the application, and can also be understood as the mutual combination of the embodiments to explain the connotation of the larger range of structure or method of the application.

[0021] Embodiment 1: A simplified modeling and optimal design method of a modular building transverse connection node, as shown in Figure 1 , comprising the following steps: Step 1. Obtain the parameters of the test specimen, use the layered shell element of the finite element software OpenSees for modeling, obtain the key calculation data, and build the constitutive relationship of the double-node element; Step 2. Establish an elastoplastic finite element model of a high-rise modular shear wall structure; Step 3. Perform elastoplastic analysis on the model, record the structure response, and calculate the damage parameter; Step 4. Determine whether to adjust the component design parameters according to the damage parameter limit value.

[0022] Embodiment 2: Based on embodiment 1, the embodiment discloses: As Figure 2 shown, in step 1: the load-mid-span deflection curve and the load-slip curve and the component deformation data are obtained by simulating the bending and shear resistance test of the transverse connection node, and the constitutive relationship of the post-cast section axial spring and the shear spring is established, and the specific steps are: Step 1.1: Component information acquisition: including (1) bending test piece information: post-cast section width, reinforcement ratio, plate total length, plate thickness, post-cast section connection height; (2) shear test piece information: reinforcement ratio of the test piece, thickness of the test piece, width of the test piece; Among them, the plate total length of the bending test piece information is 2000mm, the thickness is 120mm, and the post-cast section connection height is generally 400mm. The information needed to know for the shear test piece is mainly the reinforcement ratio of the test piece, the thickness is the same as the plate in the actual, which is 400mm, and the total width is 640mm. In order to facilitate the measurement of the shear slip of the concrete connection interface in the shear slip direction, the two side parts and the middle part are staggered by 100mm along the height direction, and the section size is 120mm*400mm.

[0023] Step 1.2: Shell element modeling to obtain post-cast section deformation data: modeling is performed using OpenSees software, layered shell elements are used to model standard bending and shear components, bending component load-deflection curves and post-cast section compression deformation and tensile deformation are obtained by simulating floor slab connection node bending test, shear component load-slip curve is obtained by simulating floor slab connection node shear test, and feature points of the two curves, namely yield point, strengthening point and failure point, are extracted; Step 1.3: Component bending mechanics balance analysis: as shown in Figure 3 , the original shell element bending model is simplified, the shell element bending floor model is divided into two rigid rectangles from the middle, and a part is simplified for stress analysis. The left part of the rigid rectangle is subjected to the support reaction force at the lower left corner, the test loading force at a distance of 2 / 3 of the length of the rigid body from the left upper corner of the rigid body, the horizontal pressure F1 at the right upper corner of the rectangular rigid body, and the horizontal tension F2 at the right lower corner of the rectangular rigid body. According to Figure 2 , the simplified mechanics of the component bending test state is established, and the stress conditions of the post-cast section compression zone and the tension zone are analyzed: ; ; ; ; ; ; In the above formula, y 挠度 is the deflection in the stress direction of the middle part of the shell element bending model, L is the length of the rectangular rigid body, L2 is the width of the rectangular rigid body, and L1=2 / 3L; The yield point, strengthening point and failure point parameters of the simulated load-deflection curve are substituted into the formula for calculating F1 and F2 in the simplified mechanics balance equation of the bending test state to calculate F1 and F2: and ; The corresponding compression force F1 and tensile force F2 of the double-node element are calculated, the deformation data of the post-cast section are combined, the three-linear hysteretic constitutive relationship in the axial direction is fitted, and the bending behavior under seismic action is simulated; Step 1.4: Component shear mechanics balance analysis: as shown in Figure 4 , the mechanical model of the shell element shear component is simplified, which is simplified into three rigid rectangles, the middle rigid rectangle is connected to the left and right rigid rectangles, the middle rigid rectangle is subjected to four shear forces, which are derived from the shear forces at the bottom of the middle rigid rectangle and the two side rigid rectangles and the shear forces at the top of the two side rigid rectangles and the middle rigid rectangle. The simplified mechanics formula F=P / 4 is established under the test state of the component shear, P is the loading load of the shear test, F is the load of the shear constitutive relationship at the characteristic points of the load-slip curve to be calculated, the yield point, strengthening point and failure point parameters of the simulated load-slip curve are substituted into the simplified mechanics formula F=P / 4 under the test state of the component shear to calculate the shear force F of the characteristic points. The slip of the constitutive relationship characteristic point is equal to the slip of the load-slip curve characteristic point, and the size of the load is the same as F, so as to obtain the constitutive curve in the shear direction of the double-node; Step 1.5: Constitutive model: The modular building transverse connection node is simulated using an element twoNodeLink, and the mechanical properties of the local x-axis and local y-axis of the twoNodeLink are defined using a uniaxialMaterial Hysteretic, that is, the bending and shear capacity of the floor connection node.

[0024] Example 3: Based on Example 1, this example discloses: As Figure 5 shown, the step 2 includes the following specific steps: Step 2.1: Shear wall element: The shear wall is simulated by a displacement-based beam-column element, the cross section of which is defined by the concrete concrete02 and steel steel02 fibers, and the rigid arm is constructed using an elastic beam-column element with an elastic modulus amplified by 1000 times, simulating the length of the shear wall cross section and connecting with the coupling beam; Step 2.2: Coupling beam element: The coupling beam is simulated by the same displacement-based beam-column element as the shear wall; Step 2.3: Two-node element: The twoNodeLink element is used to simulate the mechanical properties of the floor joint, and the corner parts of adjacent modules are connected using this element; Step 2.4: According to the following formula: The bending capacity is converted according to the connection length of the module, and the conversion formula is: ; The shear capacity is converted according to the shear area of the module, and the conversion formula is: ; The data of the standard specimen of the two-node element constitutive model established in step 1.5 is converted.

[0025] Example 4: Based on Example 1, this example discloses: The step 3 includes the following specific steps: Step 3.1, select the seismic wave: select 4 earthquake intensity: frequently occurring earthquake, fortification earthquake, rare earthquake, and extremely rare earthquake; perform elastic-plastic time history analysis on the model; Step 3.2, record the structure response data: record the displacement of each point of the structure to calculate the inter-story drift angle; record the relative displacement of the x-axis and y-axis of the two-node element in the local coordinate system, so as to obtain the compression deformation, tensile deformation and shear slip of the two-node element, and calculate the bending damage parameter and shear damage parameter; Step 3.3, calculate the bending damage parameter and shear damage parameter according to the formula respectively; Shear damage parameter calculation formula: Where δ s is the maximum relative slip in the time history analysis, δ u is the ultimate slip of the specimen at failure obtained from the test or simulation; Bending damage parameter calculation formula: Where θ s is the maximum bending deflection in the time history analysis, θ u is the ultimate bending deflection of the specimen at failure obtained from the test or simulation; According to the formula in step 1.3: According to , the is calculated.

[0026] Example 5: Based on example 1, this example discloses: The step 4 includes the following specific steps: Step 4.1: Check whether the component meets the seismic demand of the component under the four seismic intensities, specifically: Under the frequent earthquake, D s and D b should not exceed 0.08; under the fortification earthquake, D s and D b should not exceed 0.3; under the rare earthquake, D s and D b should not exceed 0.6; under the extremely rare earthquake, D s and D b should not exceed 0.8; Step 4.2: If the shear or bending damage parameter exceeds the limit value, the basic parameters of the component, i.e. the reinforcement ratio and the width of the post-cast section, should be adjusted. The adjustment formula is as follows: under different seismic intensities, the adjusted parameters will also change. This is because under the frequent earthquake, we hope that the structure remains in the elastic working state, at this time the adjustment coefficient is larger because the stiffness and strength of the structure can be greatly improved to maintain the elastic working state. Under the fortification earthquake, the rare earthquake and the extremely rare earthquake, it is difficult for the structure to remain elastic, and more is to dissipate the huge seismic energy through plastic deformation, and greatly increasing the reinforcement ratio and the width of the post-cast section connection may reduce the ductility of the structure, so the adjustment coefficient should be conservative. Therefore, different adjustment parameters should be used for different seismic intensities.

[0027] ; ; are the shear damage parameter adjustment coefficient and the bending damage parameter adjustment coefficient, respectively; As shown in the following table:

[0028] The new reinforcement ratio and the modified value of the post-cast segment connection width are obtained by the above formula, and the basic information of the component changes at this time; Step 4.3: Start again from step 1.2, based on the layered shell modeling of the specimen → obtain key point data → derive axial / shear spring force through the mechanical equilibrium equation → construct the hysteretic constitutive relationship for the dual-node element → establish the overall structure model (including the dual-node connection) → perform elastoplastic analysis → calculate damage parameters → determine whether the seismic demand is met; Step 4.4: When the demand is met, output the recommended component parameters.

[0029] Example 6: Based on the above examples, this embodiment gives a specific application example: S1: Building basic information: The building, seismic fortification intensity 8 degrees, design basic earthquake acceleration 0.2g, seismic group third group, structural damping ratio 0.05, site category II, site characteristic period 0.45s, seismic fortification class C.

[0030] S2: The information needed for the bending-resistant specimen is the post-cast segment width, reinforcement ratio, the total length of the plate is 2000mm, the thickness is 120mm, and the post-cast segment connection height is generally taken as 400mm. The information needed for the shear-resistant specimen is mainly the reinforcement ratio of the specimen, the thickness is the same as the plate in the actual, which is 400mm, and the total width is 640mm. In order to facilitate the measurement of the shear slip of the concrete connection interface in the shear slip direction, the two side components and the middle component are staggered by 100mm in the height direction, and the cross-sectional size is 120mm×400mm.

[0031] S3: Establish a shell element model to obtain the load-deflection curve and load-slip curve as shown in Figure 2 At the same time, the compression and tension of the post-cast segment of the flexural member are obtained.

[0032] S4: Define the constitutive relationship of the local x direction and the local y direction of the dual-node element, and the constitutive relationship is as shown in Figure 6 .

[0033] S5: Establishing elastic-plastic analysis model: Shear wall element: Shear wall is simulated by displacement-based beam-column element, whose cross section is defined by concrete02 and steel02 fiber, and elastic beam-column element with 1000 times enlarged elastic modulus is used to construct rigid arm to simulate the length of shear wall cross section and connect with coupling beam. Coupling beam element: Coupling beam is simulated by the same displacement-based beam-column element as shear wall. Two-node element: TwoNodeLink element is used to simulate the mechanical properties of floor joint, and this element is used to connect the corner of adjacent modules. Since the two-node element constitutive relation established in S4 is the data of standard specimen, it should be converted in the model.

[0034] S6: Performing elastic-plastic analysis: Selecting seismic wave: Selecting 4-level earthquake intensity: frequently occurring earthquake (PGA=0.07g), fortification earthquake (0.2g), rare earthquake (0.4g), and extremely rare earthquake (0.6g); performing elastic-plastic time history analysis on the model.

[0035] S7: Outputting results: Recording the displacement of each point of the structure to calculate the inter-story drift angle. Recording the relative displacement of the x-axis and y-axis of the two-node element in the local coordinate system to obtain the compression deformation, tensile deformation and shear slip of the two-node element, and to calculate the bending damage parameter and shear damage parameter. As shown in the following table:

[0036] S8: Analyzing the results: and are greater than the limit value . The design results cannot meet the design requirements, and the reinforcement ratio and post-pouring segment connection width of the component need to be adjusted.

[0037] S9: Performing over-limit adjustment: As shown in the following table:

[0038] The adjusted reinforcement ratio and post-pouring segment width should be taken as the maximum value in the table. According to the calculation results and actual engineering conditions, the reinforcement ratio is taken as 1.23%, and the post-pouring segment width is taken as 1200mm.

[0039] S10: Repeating steps S1-S8.

[0040] S11: Outputting the adjusted results, as shown in the following table:

[0041] As can be seen, and are less than the limit value , the design result is reasonable. The output adjusted component parameter is a reinforcement ratio of 1.23%, and the post-cast section width is 1200mm.

[0042] Note: When the calculated reinforcement ratio exceeds 2.5% or the post-cast section width exceeds 1800mm and still does not meet the limit value of the damage parameter, the vertical lateral force resisting member design of the structure should be checked for reasonableness.

[0043] The working principle of the application is as follows: 1. The design method provided by the application adjusts the reinforcement ratio and post-cast section connection width of the connection joint between the modular building modules, so that the limit value of the customized damage parameter is met under various seismic intensities. The limit value of the damage parameter of the connection joint can be set considering various factors, and is more in line with the aseismic design idea of performance-based seismic engineering than the current aseismic design specification.

[0044] 2. The application decouples the deformation of the connection joint under earthquakes into bending deformation and shear deformation, constructs the constitutive relationship of the shear capacity and bending capacity of the connection joint, and uses a double-node element that can define the mechanical properties in multiple directions to simulate the aseismic performance of the connection joint.

[0045] 3. Most of the current design methods modify the constitutive of concrete and steel by using the generalized modulus reduction method to simulate the influence of connection joint damage on the structure. However, this method cannot accurately obtain the stress and deformation of the connection joint, and the use of solid element modeling has too much calculation amount. In view of the distortion of the existing modulus reduction method and the low efficiency of the solid element, the double-node element is used to directly output the deformation data of the connection joint, the test data is converted by the mechanical equilibrium equation to construct the constitutive, and precise and efficient simulation is realized.

[0046] 4. The application provides an iterative design based on the dynamic elastoplastic analysis method, and the calculation method is simple, and the structure optimization design is realized through iterative design.

Claims

1. A simplified modeling and optimization design method for modular building transverse connection nodes, characterized by: The steps include: Step 1. Obtain the parameters of the test specimen, use the layered shell element of the finite element software OpenSees to model it, obtain key calculation data, and construct the constitutive relationship of the two-node element; Step 2. Establish an elastic-plastic finite element model of the high-rise modular shear wall structure; Step 3. Perform elastic-plastic analysis on the model, record the structural response, and calculate the damage parameters; Step 4. Determine whether to adjust the component design parameters based on the damage parameter limit.

2. A simplified modeling and optimization design method for modular building transverse connection nodes as claimed in claim 1, characterized in that: In step 1, the load-mid-span deflection curve and load-slip curve as well as component deformation data are obtained by simulating the bending and shear test of the transverse connection node, and the constitutive relationship of the axial spring and shear spring of the post-casting section is established. The specific steps are as follows: Step 1.1: Obtaining component information: including (1) flexural specimen information: width of post-casting section, reinforcement ratio, total length of slab, slab thickness, and post-casting section connection height; (2) shear specimen information: reinforcement ratio, specimen thickness, and specimen width; Step 1.2: Shell element modeling to obtain deformation data of the post-cast section: Modeling was performed using OpenSees software. Layered shell elements were used to model standard flexural and shear members. Simulating the flexural test of the floor slab connection nodes yielded the load-deflection curves of the flexural members and the compression deformation of the upper portion and the tensile deformation of the lower portion of the post-cast section. Simulating the shear test of the floor slab connection nodes yielded the load-slip curves of the shear members. Characteristic points of the two curves were extracted, namely the yield point, strengthening point, and failure point. Step 1.3: Mechanical equilibrium analysis of component bending: Simplify the original shell element bending model and divide the shell element bending floor model into two rigid rectangles from the middle. Perform a simplified force analysis on one part. The lower left corner of the left rigid rectangle is subjected to the support reaction force, and the test load is applied at a distance of 2 / 3 of the rigid body length from the upper left corner of the rigid body. The upper right corner of the rectangular rigid body is subjected to a horizontal pressure F1, and the lower right corner of the rectangular rigid body is subjected to a horizontal tension F2. Establish a simplified mechanical equilibrium equation for the component under the bending test state and analyze the force conditions in the compression and tension zones of the post-cast section: ； ； ； ； ； ； In the above formula, y 挠度 It is the deflection in the force direction of the middle part of the bending model using shell elements, L is the length of the rectangular rigid body, L2 is the width of the rectangular rigid body, L1=2 / 3L; Substitute the yield point, strengthening point, and failure point parameters of the simulated load-deflection curve into the simplified mechanical equilibrium equation under the bending test state to calculate the formula for F1 and F2: and ; The corresponding compression force F1 and tension force F2 of the double-node element are calculated. Combined with the deformation data of the post-casting section, the trilinear hysteresis constitutive relationship of the double-node axial direction is fitted to simulate the bending behavior under earthquake action. Step 1.4: Mechanical equilibrium analysis of components under shear: Simplify the mechanical model of the shell element shear component into three rigid rectangles. The middle rigid rectangle is connected to the left and right rigid rectangles respectively. The middle rigid rectangle is subjected to four shear forces, which come from the shear force between the bottom of the middle rigid body and the two side rigid rectangles and the shear force between the top of the two side rigid rectangles and the middle rigid rectangle; establish a simplified mechanical formula F=P / 4 for the component under shear test, where P is the applied load of the shear test and F is the load of the shear constitutive relationship at the characteristic point of the load-slip curve to be calculated; substitute the yield point, strengthening point and failure point parameters of the simulated load-slip curve into the simplified mechanical formula F=P / 4 for the component under shear test, and calculate the shear force F at the characteristic point; the slip of the characteristic point of the constitutive relationship is equal to the slip amount of the simulated load-slip curve characteristic, and the magnitude of the load is the same as F, so the constitutive curve in the double-node shear direction is obtained; Step 1.5: Constitutive construction: The modular building transverse connection nodes are simulated using double-node elements. Hysteretic materials are used to define the mechanical properties of the double-node elements in the local x-axis and local y-axis, that is, the bending and shear capacity of the floor connection nodes.

3. The simplified modeling and optimization design method for modular building transverse connection nodes according to claim 1, characterized in that: The step 2 includes the following specific steps: Step 2.1: Shear wall element: The shear wall is simulated by displacement-based beam-column elements. Its cross section is defined by concrete02 and steel02 fibers. Elastic beam-column elements with an elastic modulus magnified 1000 times are used to construct rigid arms that simulate the length of the shear wall section and connect to the coupling beam. Step 2.2: Coupling beam elements: The coupling beams are modeled using the same displacement-based beam-column elements as the shear walls. Step 2.3: Two-node element: Use twoNodeLink elements to simulate the mechanical properties of the floor joints. Use this element to connect the corners of adjacent modules. Step 2.4: According to the following formula: The bending capacity is converted according to the connection length of the module. The conversion formula is: ； The shear capacity is calculated based on the shear area of ​​the module. The conversion formula is: ； Convert the data of the standard specimen of the two-node element constitutive model established in step 1.

5.

4. The simplified modeling and optimization design method for modular building transverse connection nodes according to claim 1, characterized in that: The step 3 includes the following specific steps: Step 3.

1. Select earthquake waves: Select four earthquake intensities: frequent earthquakes, fortified earthquakes, rare earthquakes, and extremely rare earthquakes; perform elastic-plastic time history analysis on the model; Step 3.2, record structural response data: record the displacement of each point in the structure to calculate the inter-story drift angle; record the relative displacement of the two-node element in the local coordinate system along the x-axis and y-axis to obtain the compression deformation, tensile deformation, and shear slip of the two-node element to calculate the bending damage parameter and shear damage parameter; Step 3.3, calculate the bending damage parameter and shear damage parameter according to the formula; Shear damage parameter calculation formula: , where δ s is the maximum relative slip in the time history analysis, δ u It is the limit slip of the specimen at failure obtained by test or simulation; Bending damage parameter calculation formula: , where θ s is the maximum bending deflection in the time history analysis, θ u is the ultimate bending deflection of the specimen at failure obtained through testing or simulation; according to the formula in step 1.3: ,according to Calculate .

5. The simplified modeling and optimization design method for modular building transverse connection nodes according to claim 1, characterized in that: The step 4 includes the following specific steps: Step 4.1: Check whether the components meet the seismic requirements under the four earthquake intensities, specifically: Under frequent earthquakes, D s and D b Should not exceed 0.08; under earthquake protection, D s and D b It should not exceed 0.3; In rare earthquakes, D s and D b Should not exceed 0.6; in extremely rare earthquakes, D s and D b Should not exceed 0.8; Step 4.2: If the shear or bending damage parameters exceed the limit, the basic parameters of the component, namely the reinforcement ratio and the width of the post-cast section, should be adjusted. The adjustment formula is as follows: ； ； They are shear damage parameter adjustment coefficient and bending damage parameter adjustment coefficient respectively; The new reinforcement ratio and modified value of the post-casting section connection width are obtained through the above formula. At this time, the basic information of the component changes; Step 4.3: Start again from step 1.2, model the specimen based on the layered shell → obtain key point data → derive the axial / shear spring forces using the mechanical equilibrium equations → construct a hysteretic constitutive model for the two-node element → establish the overall structural model (including the two-node connection) → perform elastoplastic analysis → calculate damage parameters → determine whether the seismic requirements are met; Step 4.4: When the requirements are met, output the recommended component parameters.

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