Framework building collapse analysis method based on parametric modeling

Abstract

The invention discloses a frame building collapse analysis method based on parametric modeling. The method comprises the steps that 1, the macroscopic size, the component size, the component section reinforcement parameters and the material parameters of a frame building are preset; step 2, presetting grid division parameters; 3, the column dismantling position and dismantling time are preset; 4, generating node, unit, section and component data of the beam, the column and the plate; 5, defining an equivalent material model of the beam; 6, defining an equivalent material model of the board; 7, defining an equivalent material model of the column which is not dismantled; 8, defining an equivalent material model of the dismantled column; step 9, applying gravity and surface load; step 10, defining calculation duration, output step length and other solving control parameters, and generating a K file; and step 11, carrying out collapse calculation. According to the method, the pretreatment efficiency and the collapse calculation efficiency of frame building collapse analysis are greatly improved, the single-working-condition K file generation time is a second level, and the single-working-condition collapse calculation time is a minute level.

Description

[0001] The invention belongs to the field of building damage, and specifically relates to a building collapse analysis method, in particular to a frame building collapse analysis method based on parametric modeling. Background Art

[0002] In recent years, with the development of building damage assessment technology, building damage calculation has begun to focus on the collapse behavior of the entire building after the building components are damaged. Considering the ever-changing size and structural form of battlefield buildings, in order to support the rapid decision-making of battlefield strikes on building targets, it is urgent to establish a rapid analysis method for building collapse to support building damage assessment.

[0003] At present, building collapse analysis is often carried out using refined models, and three-dimensional solid grids are used in the refined models, which results in a long time for single collapse simulation calculation, which is difficult to meet the needs of fast pre-processing and fast calculation of collapse analysis. Considering the low efficiency of refined collapse calculation, domestic scholars have carried out a lot of research on efficient numerical simulation models for collapse in recent years. For example, Dr. Zhong Bo from Tianjin University (Research on efficient numerical simulation of damage, failure and progressive collapse analysis of reinforced concrete structures under explosion, 2017) proposed a simplified collapse analysis model for reinforced concrete frame buildings based on efficient unit models, which reduced the 297 hours of refined collapse simulation to 6 hours under typical working conditions, greatly improving the simulation efficiency; similarly, foreign scholars have also made some simplified improvements to improve the efficiency of steel structure collapse simulation (Approximations in progressive modeling, 2011, Journal of Structural Engineering).

[0004] Despite this, there are still some shortcomings in the current research on building collapse analysis: first, the collapse analysis is still time-consuming and it is difficult to calculate the collapse process in minutes; second, the collapse model pre-processing has not been parameterized, and it is difficult to quickly generate collapse calculation models for buildings of different sizes. Summary of the invention

[0005] In order to overcome the problems in the prior art that the pre-processing and calculation process of collapse analysis is time-consuming and difficult to support the rapid calculation of the collapse of buildings of different scales, the present invention provides a frame building collapse analysis method based on parametric modeling, which quickly forms a frame building model for collapse analysis through parametric input, and realizes rapid calculation of the collapse process based on the model.

[0006] In order to achieve the above tasks, the present invention adopts the following technical solutions:

[0007] A frame building collapse analysis method based on parametric modeling includes the following steps:

[0008] Step 1: Preset the macroscopic dimensions of the frame building, component dimensions, component cross-section reinforcement parameters and material parameters;

[0009] Step 2: Preset the grid division parameters of the framework building;

[0010] Step 3: Preset the column removal position and removal time;

[0011] Step 4: Use the definition format of the K file keywords in LS-DYNA to generate the node, element, section and component data of beams, columns and plates;

[0012] Step 5: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model for all beams;

[0013] Step 6: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model for all plates;

[0014] Step 7: Use the *MAT_PLASTICITY_COMPRESSION_TENSION keyword to define the equivalent material model for all columns that will not be demolished;

[0015] Step 8: Combine the *MAT_PLASTICITY_COMPRESSION_TENSION and *MAT_ADD_EROSION keywords to define the equivalent material model of the removed columns one by one. The parameters in the *MAT_PLASTICITY_COMPRESSION_TENSION keyword are the same as those in step 7. The erosion time of the column needs to be added to the *MAT_ADD_EROSION keyword. The erosion time is the removal time of each preset removed column in step 3.

[0016] Step 9: Apply loads by applying gravity and surface loads;

[0017] Step 10: Define the calculation time, output step size and other solution control parameters, and write the keyword data and solution control parameters generated in steps 4 to 9 into the keyword K file;

[0018] Step 11: Submit the keyword K file to LS-DYNA software to carry out collapse calculation, and check the calculation results through LS-PREPOST post-processing software.

[0019] Compared with the prior art, the rapid analysis method for collapse of frame buildings based on parametric modeling of the present invention has the following technical effects:

[0020] 1. The present invention proposes building parameters related to the collapse analysis of frame buildings, including building macroscopic size parameters, component size parameters, component cross-section reinforcement parameters, material parameters, column removal parameters, etc., and establishes a method and process for generating a K file for the collapse analysis of frame buildings through the above parameters, which greatly improves the pre-processing efficiency of the collapse analysis of frame buildings, and the generation time of a single working condition K file is in seconds;

[0021] 2. The present invention proposes an equivalent method for material models of beams, columns and plates. By using the above-mentioned equivalent method, the three-dimensional solid beam, column and plate component units can be simplified into one-dimensional beam units (beams, columns) and two-dimensional shell units (plates). This simplification method can greatly reduce the number of building model grids and improve the efficiency of collapse analysis. The collapse calculation time for a single working condition is only minutes. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a flow chart of the rapid analysis method of frame building collapse based on parametric modeling of the present invention;

[0023] Figure 2 It is a schematic diagram of the macroscopic size parameters of the frame building;

[0024] Figure 3 It is a schematic diagram of the index of the removed column;

[0025] Figure 4 Schematic diagram of the plate unit in the embodiment;

[0026] Figure 5 is a schematic diagram of all beams, columns, and plate elements in the embodiment;

[0027] Figure 6 is the relationship between the effective tensile (compressive) stress and the effective plastic tensile (compressive) strain of the column material in the embodiment;

[0028] Figure 7 Schematic diagram of the building collapse state at different times in the embodiment. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0030] In order to achieve the above tasks, the present invention adopts the following technical solutions: Figure 1 A flow chart of the rapid analysis method for frame building collapse based on parametric modeling is given. Specifically, it includes the following steps:

[0031] Step 1: Preset the macroscopic dimensions of the frame building, component dimensions, component section reinforcement parameters, and material parameters;

[0032] The macroscopic dimensions include the dimensions of a single room (length L, width W, height H), the dimensions of the corridor (width W′), the number of floors f, and the number of spans d, such as Figure 2As shown;

[0033] Component dimensions include beam dimensions (width W b , high H b ), column (width W c , Deep H c ), plate (thickness H p );

[0034] The reinforcement parameters of the component section include the longitudinal reinforcement ratio ρ under the beam sb 、Reinforcement ratio of all longitudinal reinforcement area of ​​column ρ sc and the longitudinal reinforcement ratio ρ below the slab sp , volume reinforcement ratio of all steel bars in the beam ρ vb , Volume reinforcement ratio of all steel bars in the column ρ vc 、Volume reinforcement ratio of all steel bars in the plate ρ vp ;

[0035] Material parameters include the density of concrete ρ c , uniaxial compressive strength of concrete σ c , the density of steel bar ρ s , the yield strength of the steel bar σ s The tensile and compressive stress-strain relationship of concrete can be determined based on the uniaxial compressive strength of concrete, and the tensile and compressive stress-strain relationship of steel bars can be determined based on the yield strength of steel bars.

[0036] Step 2: Preset the grid division parameters of the framework building;

[0037] The grid division parameters include the number of grids n1, n2, n3 in the length, width, and height directions of a single room and the number of grids n4 in the width direction of the corridor;

[0038] Step 3: Preset the column removal position and removal time. The column removal position is described by i, j, and k, such as Figure 3 As shown, i, j, k are the numbers of the positions of the columns in the length, width, and height directions, respectively, 1≤i≤d+1, 1≤j≤4, 1≤k≤f; one or more columns can be preset to be demolished, not exceeding the total number of columns in the building, and the demolition time of each column can be different.

[0039] Step 4: Generate the node, element, section and component data of beams, columns and plates using the definition format of K file keywords in LS-DYNA, including the following sub-steps:

[0040] Step 4.1: Generate mesh node data *NODE of all beams, slabs and columns according to the size of a single room (length L, width W, height H), the size of the corridor (width W′), the number of floors f, the number of spans d and the number of grids n1, n2, n3 and n4;

[0041] Step 4.2: Generate the unit data *ELEMENT_BEAM of beams and columns and the unit data *ELEMENT_SHELL of plates according to the grid node data *NODE;

[0042] Step 4.3: According to the plate thickness H p Generate the section data of the plate *SECTION_SHELL, according to the width W of the beam b , high H b and the column width W c , Deep H c Generate beam and column section data *SECTION_BEAM;

[0043] Step 4.4: Generate beam, column, and plate component data *PART. All beam units use the same *PART number, all plate units use the same *PART number, and each column that is preset to be removed in step 3 uses a unique *PART number. In addition, all other columns use the same *PART number;

[0044] Step 5: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model of all beams. The equivalent principle of the beam material model is to ensure that the bending stiffness and yield moment of the equivalent section before and after are equal, including the following steps:

[0045] Step 5.1: Calculate the cross-sectional yield curvature k of the beam by cross-sectional layer analysis method yb and yield moment M yb ,The section layered analysis method is a commonly used method in the construction field to analyze the bending capacity of a section, and will not be described in detail here;

[0046] Step 5.2: Calculate the section moment of inertia of the beam

[0047] Step 5.3: Calculate the equivalent elastic modulus of the beam

[0048] Step 5.4: Calculate the equivalent yield stress of the beam

[0049] Step 5.5: Calculate the equivalent density ρ of the beam eb =ρ c (1-ρ vb )+ρ s ρ vb ;

[0050] Step 5.6: According to E ev , σ eb , eb *MAT_PLASTIC_KINEMATIC keyword for generated beams;

[0051] Step 6: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model of all plates. The equivalent principle of the plate material model is to ensure that the bending stiffness and yield moment of the equivalent front and rear sections are equal, including the following steps:

[0052] Step 6.1: Calculate the cross-sectional yield curvature k of the plate under unit width by cross-sectional layer analysis method yp and yield moment M yp ;

[0053] Step 6.2: Calculate the section moment of inertia of the plate per unit width

[0054] Step 6.3: Calculate the equivalent elastic modulus of the plate per unit width

[0055] Step 6.4: Calculate the equivalent yield stress of the plate

[0056] Step 6.5: Calculate the equivalent density ρ of the plate ep =ρ c (1-ρ vp )+ρ s ρ vp ;

[0057] Step 6.6: According to E eb , σ eb , eb *MAT_PLASTIC_KINEMATIC keyword for generated beams;

[0058] Step 7: Use the *MAT_PLASTICITY_COMPRESSION_TENSION keyword to define the equivalent material model of all columns that are not demolished. The equivalent principle of the column material model is to ensure that the tension and compression capacities of the sections before and after the equivalent are equal, including the following steps:

[0059] Step 7.1: Calculate the tensile axial force deformation relationship F of the column based on the tensile and compressive stress-strain relationship of concrete and steel bars ct (y ct ) and compression axial force deformation relationship F cs (y cs ), where y ct ,y cs are the tensile and compressive deformations of the column, respectively, and F ct 、F cs are the tensile axial force and the compressive axial force corresponding to the deformation respectively;

[0060] Step 7.2: Calculate the effective tensile stress-effective plastic tensile strain relationship σ of the column ct (εct ) and the effective compressive stress-effective plastic compressive strain relationship σ cs (ε cs ), where ε ct , ε cs are the effective plastic tensile strain and effective plastic compressive strain of the column, σ ct , σ cs are the effective compressive stress and effective tensile stress corresponding to the effective plastic strain, respectively, which can be calculated by the following formula:

[0061]

[0062] Step 7.3: Calculate the equivalent density ρ of the column ec =ρ c (1-ρ vc )+ρ s ρ vc ;

[0063] Step 7.4: According to σ ct (ε ct ),σ cs (ε cs ),ρ ec Generates the *MAT_PLASTICITY_COMPRESSION_TENSION keyword for the column;

[0064] Step 8: Combine the *MAT_PLASTICITY_COMPRESSION_TENSION and *MAT_ADD_EROSION keywords to define the equivalent material model of the removed columns one by one. The parameters in the *MAT_PLASTICITY_COMPRESSION_TENSION keyword are the same as those in step 7. The erosion time of the column needs to be added to the *MAT_ADD_EROSION keyword. The erosion time is the removal time of each preset removed column in step 3.

[0065] Step 9: Apply loads by applying gravity and surface loads, including the following steps:

[0066] Step 9.1: Apply gravity loads to all *PARTs using the *LOAD_GRAVITY_PART keyword;

[0067] Step 9.2: Apply the surface load through the *LOAD_SEGMENT_SET keyword. The location of the applied surface load can be defined by the keyword *SET_SEGMENT.

[0068] Step 10: Define the calculation time, output step size and other solution control parameters, and write the keyword data and solution control parameters generated in steps 4 to 9 into the K file;

[0069] Step 11: Submit the keyword K file to LS-DYNA software to carry out collapse calculation, and check the calculation results through LS-PREPOST post-processing software.

[0070] The present invention is further described in detail below through specific examples.

[0071] Embodiment 1:

[0072] This embodiment takes a typical 6-story, 6-span inner corridor frame building as the object, and carries out parametric modeling and rapid collapse analysis, including the following steps:

[0073] Step 1: Preset the macroscopic dimensions of the frame building, component dimensions, component section reinforcement parameters, and material parameters;

[0074] The macro dimensions include the size of a single room (3m long, 3m wide, and 1.75m high), the size of the corridor (1m wide), the number of floors is 6, and the number of spans is 6;

[0075] Component dimensions include beam dimensions (width 0.175m, height 0.35m), columns (width 0.2m, depth 0.2m), and plates (thickness 0.09m);

[0076] The reinforcement parameters of the component section include the longitudinal reinforcement ratio of 1% under the beam, the area reinforcement ratio of all longitudinal reinforcements in the column of 2%, the longitudinal reinforcement ratio of 0.3% under the slab, the volume reinforcement ratio of all steel bars in the beam of 2%, the volume reinforcement ratio of all steel bars in the column of 2.5%, and the volume reinforcement ratio of all steel bars in the slab of 0.5%;

[0077] Material parameters include the density of concrete 2300kg / m 3 , uniaxial compressive strength of concrete 40MPa, density of steel bar 7800kg / m 3 , the yield strength of the steel bar is 400MPa. The tensile and compressive stress-strain relationship of the concrete can be determined based on the uniaxial compressive strength of the concrete, and the tensile and compressive stress-strain relationship of the steel bar can be determined based on the yield strength of the steel bar;

[0078] The compressive stress-strain relationship of concrete in this embodiment is as follows:

[0079]

[0080] Among them, ε c and σ c are the compressive strain and corresponding compressive stress of concrete, E0 is the initial elastic modulus, ε0 and σ0 are the strain and stress corresponding to the ultimate stress position, E s =σ0 / ε0; due to the low tensile strength of concrete, it is ignored in this embodiment.

[0081] The stress-strain relationship of the steel bars in this embodiment is as follows

[0082]

[0083] Among them, ε s and σ s are the longitudinal reinforcement strain and stress, E s is Young's modulus, f y is the yield stress, ε y is the yield strain, ε u is the fracture strain.

[0084] Step 2: Preset the grid division parameters of the framework building;

[0085] The grid division parameters include the number of grids in the length, width, and height directions of a single room being 10, 10, and 10 respectively, and the number of grids in the width direction of the corridor being 3;

[0086] Step 3: Preset the column removal position and removal time. The column removal position is described by i, j, k. i, j, k are the numbers of the column positions in the length, width, and height directions, respectively. 1≤i≤d+1, 1≤j≤4, 1≤k≤f. One or more columns can be preset to be removed, and the maximum number of columns in the building cannot exceed that. The removal time of each column can be different.

[0087] In this embodiment, the removal position and removal time index are shown in Table 1.

[0088] Table 1 Index of removed columns and removal time

[0089]

[0090]

[0091] Step 4: Use the definition format of the K file keywords in LS-DYNA to generate the node, unit, section and component data of beams, columns and plates, including the following steps:

[0092] Step 4.1: Generate mesh node data *NODE of all beams, slabs and columns according to the size of a single room (length L, width W, height H), the size of the corridor (width W′), the number of floors, the number of spans and the number of grids;

[0093] Step 4.2: Generate the unit data *ELEMENT_BEAM of beams and columns and the unit data *ELEMENT_SHELL of plates according to the grid node data *NODE; Figure 4 A top view of the plate grid is given;

[0094] Step 4.3: According to the plate thickness H p Generate the section data of the plate *SECTION_SHELL, according to the width W of the beam b, high H b and the column width W c , Deep H c Generate beam and column section data *SECTION_BEAM; Figure 5 All beam, column and slab mesh diagrams are given;

[0095] Step 4.4: Generate beam, column, and plate component data *PART. All beam units use the same *PART number, all plate units use the same *PART number, and each column that is preset to be removed in step 3 uses a unique *PART number. In addition, all other columns use the same *PART number;

[0096] Step 5: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model of all beams. The equivalent principle of the beam material model is to ensure that the bending stiffness and yield moment of the equivalent section before and after are equal, including the following steps:

[0097] Step 5.1: Calculate the cross-sectional yield curvature k of the beam by cross-sectional layer analysis method yb =0.009 / m and yield moment M yb =48940N, the cross-section layered analysis method is a common method for analyzing the bending capacity of cross-sections in the construction field, and will not be described here;

[0098] Step 5.2: Calculate the section moment of inertia of the beam

[0099] Step 5.3: Calculate the equivalent elastic modulus of the beam

[0100] Step 5.4: Calculate the equivalent yield stress of the beam

[0101] Step 5.5: Calculate the equivalent density ρ of the beam eb =ρ c (1-ρ vb )+ρ s ρ vb =2.41g / cm 3 ;

[0102] Step 5.6: According to E eb , σ eb , eb *MAT_PLASTIC_KINEMATIC keyword for generated beams;

[0103] Step 6: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model of all plates. The equivalent principle of the plate material model is to ensure that the bending stiffness and yield moment of the equivalent front and rear sections are equal, including the following steps:

[0104] Step 6.1: Calculate the cross-sectional yield curvature k of the plate under unit width by cross-sectional layer analysis method yp =0.038 / m and yield moment M yρ =25700N;

[0105] Step 6.2: Calculate the section moment of inertia of the plate per unit width

[0106] Step 6.3: Calculate the equivalent elastic modulus of the plate per unit width

[0107] Step 6.4: Calculate the equivalent yield stress of the plate

[0108] Step 6.5: Calculate the equivalent density ρ of the plate ep =ρ c (1-ρ vp )+ρ s ρ vp =2.33g / cm 3 ;

[0109] Step 6.6: According to E eb , σ eb , eb *MAT_PLASTIC_KINEMATIC keyword for generated beams;

[0110] Step 7: Use the *MAT_PLASTICITY_COMPRESSION_TENSION keyword to define the equivalent material model of all columns that are not demolished. The equivalent principle of the column material model is to ensure that the tension and compression capacities of the sections before and after the equivalent are equal, including the following steps:

[0111] Step 7.1: Calculate the tensile axial force deformation relationship F of the column based on the tensile and compressive stress-strain relationship of concrete and steel bars ct (y ct ) and compression axial force deformation relationship F cs (y cs );

[0112] Step 7.2: Calculate the equivalent tensile effective plastic stress-strain relationship σ of the column ct (ε ct ) and the equivalent compressive effective plastic stress-strain relationship σ cs (ε cs ),like Figure 6 As shown;

[0113] Step 7.3: Calculate the equivalent density ρ of the column ec =ρ c (1-ρvc )+ρ s ρ vc =2.44g / cm 3 ;

[0114] Step 7.4: According to σ ct (ε ct ),σ cs (v cs ),ρ ec Generates the *MAT_PLASTICITY_COMPRESSION_TENSION keyword for the column;

[0115] Step 8: Combine the *MAT_PLASTICITY_COMPRESSION_TENSION and *MAT_ADD_EROSION keywords to define the equivalent material model of the removed columns one by one. The parameters in the *MAT_PLASTICITY_COMPRESSION_TENSION keyword are the same as those in step 7. The erosion time of the column needs to be added to the *MAT_ADD_EROSION keyword. The erosion time is the removal time of each preset removed column in step 3.

[0116] Step 9: Apply loads by applying gravity and surface loads, including the following steps:

[0117] Step 9.1: Apply gravity load to all *PARTs through the *LOAD_GRAVITY_PART keyword. In this example, the gravity acceleration of all parts is 9.8m / s. 2 ;

[0118] Step 9.2: Apply surface loads through the *LOAD_SEGMENT_SET keyword as required by the analysis. In this example, the uniformly distributed load on all panels is 4 kN / m 2 ;

[0119] Step 10: Define the calculation time as 2s and the output step as 0.1s, and write the keyword data and solution control parameters generated in steps 4 to 9 into the keyword K file;

[0120] Step 11: Submit the keyword K file to LS-DYNA software to carry out collapse calculation, and check the calculation results through LS-PREPOST post-processing software. Figure 7The collapse process of the building after the removal of 8 columns is shown. The pre-processing and collapse calculation time is about 5 minutes in total. In comparison, if the traditional refined collapse simulation method is used, the pre-processing and collapse calculation time is not less than 24 hours. Compared with the efficient collapse analysis method in recent years, the pre-processing and collapse calculation time is still not less than 6 hours (refer to the estimation results of the following literature: Research on efficient numerical simulation of damage and progressive collapse analysis of reinforced concrete structures under explosion [D], 2017, doctoral dissertation of Tianjin University). It can be seen that compared with the existing collapse analysis method, the present invention has a significant improvement in calculation efficiency.

Claims

1. A frame building collapse analysis method based on parametric modeling, characterized in that: The steps include: Step 1: Preset the macroscopic dimensions of the frame building, component dimensions, component cross-section reinforcement parameters and material parameters; Step 2: Preset the grid division parameters of the framework building; Step 3: Preset the column removal position and removal time; Step 4: Use the definition format of the K file keywords in LS-DYNA to generate the node, element, section and component data of beams, columns and plates; Step 5: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model for all beams; Step 6: Use the *MAT_PLASTIC_KINEMATIC keyword to define the equivalent material model for all plates; Step 7: Use the *MAT_PLASTICITY_COMPRESSION_TENSION keyword to define the equivalent material model for all columns that are not to be demolished; Step 8: Combine the *MAT_PLASTICITY_COMPRESSION_TENSION and *MAT_ADD_EROSION keywords to define the equivalent material model of the removed columns one by one. The parameters in the *MAT_PLASTICITY_COMPRESSION_TENSION keyword are the same as those in step 7. The erosion time of the column needs to be added to the *MAT_ADD_EROSION keyword. The erosion time is the removal time of each preset removed column in step 3. Step 9: Apply loads by applying gravity and surface loads; Step 10: Define the calculation time, output step size and other solution control parameters, and write the keyword data and solution control parameters generated in steps 4 to 9 into the keyword K file; Step 11: Submit the keyword K file to LS-DYNA software to carry out collapse calculation, and check the calculation results through LS-PREPOST post-processing software.

2. The rapid analysis method for collapse of frame buildings based on parametric modeling as claimed in claim 1, characterized in that: In step 1, the macro dimensions include the size of a single room, the size of the corridor, the number of floors f, and the number of spans d; the room dimensions include length L, width W, and height H; the corridor dimensions include width W ′ ; Component sizes include beam size, column size, and plate size; Beam dimensions include width W b , high H b ; Column dimensions include width W c , Deep H c ; Plate size includes thickness H p ; The reinforcement parameters of the component section include the longitudinal reinforcement ratio ρ under the beam sb 、Reinforcement ratio of all longitudinal reinforcement area of ​​column ρ sc and the longitudinal reinforcement ratio ρ below the slab sp , volume reinforcement ratio of all steel bars in the beam ρ vb , Volume reinforcement ratio of all steel bars in the column ρ vc 、Volume reinforcement ratio of all steel bars in the plate ρ vp ; Material parameters include the density of concrete ρ c , uniaxial compressive strength of concrete σ c , the density of steel bar ρ s , the yield strength of the steel bar σ s ; In step 2, the grid division parameters include the number of grids n1, n2, n3 in the length, width, and height directions of a single room and the number of grids n4 in the width direction of the corridor.

3. The frame building collapse analysis method based on parametric modeling as claimed in claim 2, characterized in that: In step 3, the column removal position is described by i, j, and k, where i, j, and k are the numbers of the column positions in the length, width, and height directions, respectively, 1≤i≤d+1, 1≤j≤4, 1≤k≤f 4. The frame building collapse analysis method based on parametric modeling as claimed in claim 3, characterized in that: Step 4 includes the following sub-steps: Step 4.1: Based on the size of a single room, the size of the corridor, the number of floors f, the number of spans d, and the number of grids n c , n2, n3, n4, generate the mesh node data *NODE of all beams, plates and columns; Step 4.2: Generate the unit data *ELEMENT_BEAM of beams and columns and the unit data *ELEMENT_SHELL of plates according to the grid node data *NODE; Step 4.3: According to the plate thickness H p Generate the section data of the plate *SECTION_SHELL, according to the width W of the beam b , high H b and the column width W c , Deep H c Generate beam and column section data *SECTION_BEAM; Step 4.4: Generate beam, column, and plate component data *PART. All beam units use the same *PART number, all plate units use the same *PART number, and each column that is preset to be demolished in step 3 uses a unique *PART number. In addition, all other columns use the same *PART number.

5. The frame building collapse analysis method based on parametric modeling as claimed in claim 4, characterized in that: Step 5 includes the following steps: Step 5.1: Calculate the cross-sectional yield curvature k of the beam by cross-sectional layer analysis method yb and yield moment M yb ; Step 5.2: Calculate the section moment of inertia of the beam Step 5.3: Calculate the equivalent elastic modulus of the beam Step 5.4: Calculate the equivalent yield stress of the beam Step 5.5: Calculate the equivalent density ρ of the beam eb =ρ c (1-ρ vb )+ρ s ρ vb ; Step 5.6: According to E eb , σ eb , eb Generates the *MAT_PLASTIC_KINEMATIC keyword for beams.

6. The frame building collapse analysis method based on parametric modeling as claimed in claim 5, characterized in that: Step 6 includes the following steps: Step 6.1: Calculate the cross-sectional yield curvature k of the plate under unit width by cross-sectional layer analysis method yp and yield moment M yp ; Step 6.2: Calculate the section moment of inertia of the plate per unit width Step 6.3: Calculate the equivalent elastic modulus of the plate per unit width Step 6.4: Calculate the equivalent yield stress of the plate Step 6.5: Calculate the equivalent density ρ of the plate ep =ρ c (1-ρ vp )+ρ s ρ vp ; Step 6.6: According to E eb , σ eb , eb Generates the *MAT_PLASTIC_KINEMATIC keyword for the plate.

7. The frame building collapse analysis method based on parametric modeling as claimed in claim 6, characterized in that: Step 7 includes the following steps: Step 7.1: Calculate the tensile axial force deformation relationship F of the column based on the tensile and compressive stress-strain relationship of concrete and steel bars ct (y ct ) and compression axial force deformation relationship F cs (y cs ), where y ct ,y cs are the tensile and compressive deformations of the column, respectively, and F ct 、F cs are the tensile axial force and the compressive axial force corresponding to the deformation respectively; Step 7.2: Calculate the equivalent tensile effective plastic stress-strain relationship σ of the column ct (ε ct ) and the equivalent compressive effective plastic stress-strain relationship σ cs (ε cs ), where ε ct , ε cs are the effective plastic tensile strain and effective plastic compressive strain of the column, σ ct , σ cs are the effective compressive stress and effective tensile stress corresponding to the effective plastic strain, respectively, which can be calculated by the following formula: Step 7.3: Calculate the equivalent density ρ of the column ec =ρ c (1-ρ vc )+ρ s ρ vc ; Step 7.4: According to σ ct (ε ct ),σ cs (ε cs ),ρ ec Generates the *MAT_PLASTICITY_COMPRESSION_TENSION keyword for the column; 8. The frame building collapse analysis method based on parametric modeling as claimed in claim 7, characterized in that: Step 9 includes the following steps: Step 9.1: Apply gravity loads to all *PARTs using the *LOAD_GRAVITY_PART keyword; Step 9.2: Apply the surface load using the *LOAD_SEGMENT_SET keyword.

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