Corrugated steel plate reinforced composite structure and method for evaluating post-seismic collapse resistance thereof

Abstract

The application discloses a corrugated steel plate reinforced combined structure and a post-earthquake anti-collapse performance evaluation method thereof, and relates to the technical field of fabricated steel structures. The corrugated steel plate reinforced combined structure comprises an H-shaped steel beam assembly, a square steel tube and a plurality of corrugated steel plates. The H-shaped steel beam assembly comprises a plurality of sequentially connected H-shaped steel beams. One end of the H-shaped steel beam assembly is fixedly connected to one side of the square steel tube. The H-shaped steel beams are fixed through a set beam-column joint connection mode. Two corrugated steel plates are arranged at the beam-column joint connection positions of every two H-shaped steel beams. The application tests the anti-seismic performance, the anti-collapse performance and the post-earthquake anti-collapse stress performance of the corrugated steel plate reinforced combined structure, so as to accurately evaluate the post-earthquake anti-collapse performance of the corrugated steel plate reinforced combined structure.

Description

Technical Field

[0001] This invention relates to the field of prefabricated steel structure technology, and in particular to a corrugated steel plate reinforced composite structure and its method for evaluating its anti-collapse performance after seismic damage. Background Technology

[0002] Prefabricated steel structures, as a type of green building structure with a complete life cycle, are characterized by standardized design, factory production, assembly construction, integrated decoration, and information management. During normal use, these structures may experience various accidental loads, leading to structural collapse. The causes of structural collapse can be divided into two categories: first, under seismic loading, the structure undergoes inelastic large deformation and component instability, resulting in the failure of load transmission paths; second, impacts, explosions, or human-caused damage cause the failure of some load-bearing components, blocking load transmission paths.

[0003] Based on the aforementioned causes of collapse, the analysis of damage evolution in frame structures typically relies on the failure phenomena observed in frame tests, damage indices, and stress development from finite element analysis to study the damage evolution patterns of frame structures. However, most current seismic damage models are specifically designed for the entire structure or individual components, while research on comprehensive evaluation models of damage to key components in composite structures is limited. Similarly, there is a lack of studies on the evolution of damage accumulation during the collapse resistance process after seismic damage in composite structures. Traditional prefabricated building structures are prone to damage accumulation at joints under seismic loading. Such buildings may suffer secondary damage from human activities or unexpected disasters within their service life, causing the initial localized damage to spread to other components, leading to widespread collapse or even the continuous collapse of the entire structure. Summary of the Invention

[0004] The purpose of this invention is to provide a corrugated steel plate reinforced composite structure and a method for evaluating its post-earthquake collapse resistance, which can accurately evaluate the post-earthquake collapse resistance of the corrugated steel plate reinforced composite structure.

[0005] To achieve the above objectives, the present invention provides the following solution: A corrugated steel plate reinforced composite structure includes: an H-beam assembly, square steel tubes, and multiple corrugated steel plates; the H-beam assembly includes multiple H-beams connected in sequence. One end of the H-beam assembly is fixedly connected to one side of the square steel tube; each H-beam is fixed to the others by a set beam-column joint connection method; two corrugated steel plates are provided at the beam-column joint connection position of every two H-beams.

[0006] Optionally, the beam-column joint connection method adopts bolted connection or bolt-welded hybrid connection.

[0007] Optionally, the bolted connection is: the top, middle and bottom of each H-beam are fixed together by bolts.

[0008] Optionally, the bolted-welded hybrid connection is as follows: the top and bottom of each H-beam are fixed by welding; the middle parts of each H-beam are fixed by bolts.

[0009] This invention also provides a method for evaluating the post-earthquake collapse resistance of a corrugated steel plate reinforced composite structure, applicable to the aforementioned corrugated steel plate reinforced composite structure, comprising: The corrugated steel plate reinforced composite structure was fixed on the experimental device, and low-cycle repeated loading was applied according to the procedures specified in the AISC seismic code to determine the collaborative seismic data of the corrugated steel plate reinforced composite structure. The collaborative seismic data included: failure mode, damage evolution, bearing capacity, ductility, stiffness degradation, and energy dissipation capacity. A seismic resilience model is constructed based on the aforementioned collaborative seismic resistance data; By using the quasi-static unidirectional loading method until the specimen of the corrugated steel plate reinforced composite structure fails, the load-displacement relationship is determined through the development law of bending effect and catenary effect at different nodes; Establish a node failure criterion based on the load-displacement relationship; Using a force-displacement loading regime and a unidirectional loading method, the specimens of the corrugated steel plate reinforced composite structure were loaded, and the nodal energy dissipation and bearing capacity parameters under different loading states were recorded. Based on the seismic test results, seismic damage evaluation indicators and seismic damage degree were formulated. Based on the seismic resilience model, the node failure criterion, the seismic damage evaluation index, and the degree of seismic damage, a comprehensive risk assessment system oriented towards earthquake-collapse is constructed, and the post-earthquake collapse resistance performance is evaluated using the comprehensive risk assessment system oriented towards earthquake-collapse.

[0010] Optionally, the method for determining the collaborative seismic data is as follows: The corrugated steel plate reinforced composite structure was fixed on the experimental device, and low-cycle cyclic loading was applied according to the procedures specified in the AISC seismic code. Finite element models of specimens with different beam-column joint connection methods were established using the finite element software ABAQUS, and the numerical model was verified by actual test results. Then, the influence of the key parameters of the corrugated steel plate on the seismic performance of the specimens was tested to obtain the stress distribution and internal force changes of the corrugated steel plate reinforced composite structure, as well as the synergistic seismic data under low-cycle cyclic loading.

[0011] Optionally, establishing the nodal failure criterion based on the load-displacement relationship specifically includes: Using the finite element software ABAQUS and the load-displacement relationship, finite element models of specimens with different beam-column joint connection methods were established. The stress distribution and internal force changes of the corrugated steel plate reinforced composite structure were analyzed by numerical model. The stress characteristics of the joint area in the elastic deformation and plastic deformation stages were studied, and the mechanism of bending effect and catenary effect was determined. The damage and fracture evolution process is reproduced by numerical simulation. The stress distribution of the flange and web sections at different stress stages is extracted, the fracture occurrence law is analyzed, and the fracture failure law caused by different parameters is obtained. Based on the damage evolution process and failure mode of the corrugated steel plate reinforced composite structure under different parameters, the damage accumulation law of beam-column joints is obtained, thereby determining the qualitative description and quantitative index of different damage states. According to the ultimate deformation and cumulative deformation energy consumption of the beam-column substructure, a new failure criterion for ductile joints considering the catenary effect is established.

[0012] Optionally, the method for constructing the comprehensive risk assessment system for earthquake-collapse is as follows: Based on the finite element software ABAQUS, the seismic restoring force model, the node failure criterion, the seismic damage evaluation index and the degree of seismic damage, the bearing capacity and deformation capacity, node failure mode and force transmission characteristics of the reinforced composite structure under different parameters in the face of earthquake-collapse, as well as the evolution process of bending mechanism and suspension mechanism. The influence of various parameters on the substructure bearing capacity, failure mechanism, shear deformation and energy dissipation of the core area of ​​the corrugated steel plate reinforced composite structure was analyzed. The development law of the anti-collapse performance of the reinforced composite structure after earthquake damage under multi-parameter variation conditions was obtained. Based on the law analysis results and the calculation method of anti-collapse bearing capacity after earthquake damage, a comprehensive risk assessment system for earthquake-collapse was established.

[0013] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects: This invention discloses a corrugated steel plate reinforced composite structure and its post-earthquake collapse resistance assessment method. The corrugated steel plate reinforced composite structure includes: an H-beam assembly, a square steel tube, and multiple corrugated steel plates. The H-beam assembly comprises multiple sequentially connected H-beams. One end of the H-beam assembly is fixedly connected to one side of the square steel tube. The H-beams are fixed together by a predetermined beam-column joint connection method. Two corrugated steel plates are placed at the beam-column joint connection position of every two H-beams. Based on the corrugated steel plate reinforced composite structure, this invention performs seismic performance tests, collapse resistance tests, and post-earthquake collapse resistance stress tests on it, achieving an accurate assessment of the post-earthquake collapse resistance of the corrugated steel plate reinforced composite structure. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a flowchart illustrating the post-earthquake collapse resistance assessment method of the present invention. Figure 2 A schematic diagram is constructed for the evaluation method in this embodiment; Figure 3 This is a schematic diagram of the combined substructure specimen in this embodiment; wherein, (a) is a structural diagram of the quasi-static test specimen of the fully bolted joint; (b) is a structural diagram of the quasi-static test specimen of the bolted-welded hybrid joint; (c) is a structural diagram of the collapse test specimen of the fully bolted joint; (d) is a structural diagram of the collapse test specimen of the bolted-welded hybrid joint; (e) is a structural diagram of the collapse test specimen of the corrugated steel plate welded-fully bolted reinforced joint; and (f) is a structural diagram of the collapse test specimen of the corrugated steel plate welded-bolted-welded hybrid reinforced joint. Figure 4 This is a technical roadmap for the research in this embodiment. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] The purpose of this invention is to provide a corrugated steel plate reinforced composite structure and a method for evaluating its post-earthquake collapse resistance, which can accurately evaluate the post-earthquake collapse resistance of the corrugated steel plate reinforced composite structure.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] The present invention provides a corrugated steel plate reinforced composite structure, comprising: an H-beam assembly, a square steel tube and a plurality of corrugated steel plates; the H-beam assembly comprises a plurality of H-beams connected in sequence.

[0020] One end of the H-beam assembly is fixedly connected to one side of the square steel tube; each H-beam is fixed to the others by a set beam-column joint connection method; two corrugated steel plates are provided at the beam-column joint connection position of every two H-beams.

[0021] In one specific implementation, the beam-column joint connection method adopts either bolted connection or a hybrid bolted-welded connection. The bolted connection involves fixing the top, middle, and bottom of each H-beam with bolts. The hybrid bolted-welded connection involves fixing the top and bottom of each H-beam with welding, and fixing the middle sections of each H-beam with bolts.

[0022] Based on the above structure, when the flange of the frame beam undergoes large deformation and cracking, the corrugated steel plate crosses the cracked flange, thus forming a new force transmission path in the joint area. This prevents the crack originating from the beam flange from continuing to develop in the beam web, thereby preventing progressive collapse of the structure. Through systematic quasi-static tests and collapse tests of the corrugated steel plate reinforced composite joint, the seismic and collapse resistance mechanism of this joint is revealed. A comprehensive stress performance and design method for this joint under seismic and progressive collapse conditions are proposed, and a complete set of theoretical design methods is summarized, providing a complete theoretical design foundation and paving the way for the accelerated upgrading of the construction industry as a whole.

[0023] like Figure 1 As shown, the present invention also provides a method for evaluating the post-earthquake collapse resistance performance of a corrugated steel plate reinforced composite structure, applied to the aforementioned corrugated steel plate reinforced composite structure, comprising: Step 100: Fix the corrugated steel plate reinforced composite structure onto the experimental device, and apply low-cycle repeated loading according to the procedures specified in the AISC seismic code to determine the collaborative seismic data of the corrugated steel plate reinforced composite structure; the collaborative seismic data includes: failure mode, damage evolution, bearing capacity, ductility, stiffness degradation, and energy dissipation capacity; Step 200: Construct a seismic resilience model based on the collaborative seismic resistance data; Step 300: Using the quasi-static unidirectional loading method until the specimen of the corrugated steel plate reinforced composite structure fails, determine the load-displacement relationship by observing the development law of bending effect and catenary effect at different nodes; Step 400: Establish a nodal failure criterion based on the load-displacement relationship; Step 500: Using the force-displacement loading regime and unidirectional loading method, load the specimen of the corrugated steel plate reinforced composite structure, record the nodal energy dissipation and bearing capacity parameters under different loading states, and formulate seismic damage evaluation index and seismic damage degree based on the seismic test results; Step 600: Based on the seismic recovery force model, the node failure criterion, the seismic damage evaluation index and the degree of seismic damage, construct a comprehensive risk assessment system for earthquake-collapse, and use the comprehensive risk assessment system for earthquake-collapse to evaluate the post-earthquake collapse resistance performance.

[0024] Based on the above evaluation methods, support will be provided for the application of steel structures in industrialization and prefabricated buildings. Research will be conducted on novel reinforced composite structures and multi-hazard resilience defense of frames, employing a combination of experimental research, finite element simulation, and theoretical analysis to investigate their seismic performance of beam-column joints, resistance to progressive collapse, and safety performance under multi-hazard coupling conditions. The inherent logical relationships between the research topics and sub-topics derived from each research content will be discussed, such as... Figure 2 As shown.

[0025] The specific research content is as follows: (1) Research on the seismic performance of a new type of reinforced composite structure 1) This study focuses on the similarities and differences in the stress mechanisms and working mechanisms between novel reinforced composite structures and traditional composite structures. Different node connection methods, reinforcement forms, and experimental parameters are designed. Quasi-static tests are used to reveal the collaborative working mechanism, energy dissipation mechanism, hysteresis characteristics, damage distribution, and failure modes of corrugated steel plates and steel beams. The influence of key design parameters on the initial stiffness, bearing capacity, energy dissipation capacity, ductility, and failure mode of the novel reinforced composite nodes is clarified. Furthermore, calculation formulas for the initial stiffness, sliding load, yield load, and ultimate load of the novel reinforced composite nodes are proposed, as shown below. Based on the principle of equivalent bending bearing capacity of traditional composite nodes, a design theory for novel reinforced beam-column composite nodes is established; and the optimal values ​​for the construction and arrangement parameters of the corrugated plate at the reinforced nodes are determined.

[0026] ; in, For initial stiffness, For the initial stiffness of the plate, The initial stiffness of the corrugated steel plate, To contribute stiffness to the connection, Slip load, For bolt slip load, For the tensile load of the corrugated steel plate, For yield load, The yield load at the connection point. To contribute yield load to corrugated steel plate For ultimate bearing capacity, This is the ultimate load at the connection point. Ultimate load of corrugated steel plate.

[0027] 2) Establish a finite element model that considers material nonlinearity, geometric nonlinearity, contact nonlinearity, and damage accumulation; study other factors besides those considered in the experiment (including structural plate construction parameters at the connection points, etc.); optimize the design parameters and process of the new reinforced composite frame; evaluate the seismic performance and post-earthquake repair performance of the new reinforced composite structure; improve the design theory of the new composite node; establish a node restoring force model; and create conditions for the elastoplastic time history analysis of reinforced composite frame structures under rare earthquakes.

[0028] (2) Research on the collapse resistance of novel reinforced composite structures 1) This study investigates the collaborative working mechanism of the steel beam and corrugated plate, as well as the stress-strain development law in the corrugated steel plate connection area, when the joint is in the small deformation stage after the central column is removed. It analyzes the load-displacement relationship and the contribution distribution of bending effect in the normal service stage of the novel composite structure. Furthermore, it clarifies the contribution of the corrugated steel plate in resisting progressive collapse during the large deformation stage, revealing the relationship between the rotational capacity of the novel reinforced composite structure and the degree of catenary effect development, and proposes a simplified assessment method for progressive collapse. Based on the principle of functional equilibrium, it studies the structural dynamic response during the collapse process, clarifying the development trend after the initial fracture occurs in the local area of ​​the structure.

[0029] 2) The system analyzes the damage and fracture evolution process and failure mechanism of the novel reinforced composite structure, extracts the vulnerable areas in the substructures, and studies their complex stress and strain distribution and development. It determines the failure sequence and final failure mode of each component and connection in the three-dimensional overall structural system. The system qualitatively describes the different damage states of these components during collapse and quantifies the specific damage degree of the corrugated steel plate, upper and lower flanges, and web, establishing failure criteria for the novel reinforced composite joint. Using the ultimate bearing capacity calculation method for specimens under different damage degrees, it obtains a structural anti-progressive collapse analysis model considering the influence of various key design parameters. Furthermore, it studies the influence of different corrugated plate structural design parameters on the damage and crack initiation point location of the beam splice area, proposing a reasonable parameter range for the reasonable shape and structural dimensions of the corrugated steel plate.

[0030] (3) Study on the anti-collapse stress performance of a new type of reinforced composite structure after earthquake damage 1) This study investigates the damage modes of novel reinforced composite structures under earthquakes of varying magnitudes, clarifying the collaborative working mechanism of each component under different seismic damage conditions, including the overall buckling mechanism, failure phenomena, energy dissipation capacity, and bearing capacity. It proposes a novel damage assessment index for reinforced composite joints to quantify the damage state of joints under seismic damage conditions. Seismic damage evolution time-history analysis is conducted, and a corresponding seismic damage model is established. The rationality of the proposed structural damage model is clarified through multi-dimensional verification using quasi-static test results, simplified calculations, and numerical simulations.

[0031] 2) Conduct progressive collapse tests on novel reinforced composite structures under seismic damage conditions. This transitions from seismic analysis of the novel reinforced composite structure to structural collapse analysis, investigating the internal force distribution, deformation, and crack development patterns of the reinforced composite structure under seismic damage conditions when the central column is removed. The interaction mechanism of its progressive collapse force transmission is also studied. A finite element model considering cumulative damage and post-earthquake residual deformation is established to study the distribution of vulnerable areas in the structural members during progressive collapse, determining whether the novel reinforced composite structure can form an effective alternative force transmission path during collapse under seismic damage conditions. Based on the collapse performance under different seismic damage conditions, corresponding formulas for calculating the collapse bearing capacity are established, as shown below.

[0032] ; in, For ultimate bearing capacity, For the shear resistance of the bolt, This represents the bolt damage coefficient. The damage coefficient of the corrugated steel plate. The load-bearing capacity of corrugated steel plates Weld damage coefficient, Load-bearing capacity at weld joints.

[0033] As a further implementation process, the purpose of this embodiment is to solve the following problems: (1) the quantitative assessment model and damage law of the corrugated steel plate reinforced composite node; (2) the seismic and collapse resistance performance of the corrugated steel plate reinforced composite node and the synergistic mechanism of each component; (3) the transformation law of the three force transmission mechanisms of the arching effect, the bending effect and the catenary effect during the collapse process; (4) the change law of the collapse resistance performance under different seismic damage states and the structural collapse risk assessment.

[0034] (1) Specific experimental procedures for the seismic performance of the new reinforced composite structure: We plan to conduct low-cycle cyclic loading tests on two novel reinforced composite joints. To ensure the comparability of the test results, the steel beams used in the specimens will have the same overall features and geometric dimensions, as shown in the attached figure. Figure 3As shown in (a)-(b), the main change is in the node connection method, which is a combination of bolted and welded connections. A stationary hinge constraint device is used at the bottom of the structural column, and the hinge support is fixed to the rigid support with multiple high-strength bolts. The support is connected to the reaction floor to achieve an effective hinge boundary. Lateral constraint devices are installed to limit the out-of-plane movement of the specimen during loading; therefore, lateral supports are added at both ends. In addition, a constant axial pressure of approximately 30% of the column yield pressure is applied at the top of the column using vertical jacks. Low-cycle repetitive loads are applied at the free ends of the left and right beams using vertically placed hydraulic servo systems, and the loading is carried out according to the procedures specified in the AISC seismic design code. The force transmission path, plastic damage distribution, and energy dissipation mechanism of the novel reinforced composite node are clarified, providing experimental data for verifying the design theory of the novel reinforced composite node and establishing a node restoring force model.

[0035] Based on the finite element software ABAQUS, refined finite element models of two specimens were established, and the numerical models were verified by actual experimental results. Then, the influence of key parameters such as the dimensions, type, and welding position of the corrugated steel plate on the seismic performance of the specimens was considered, revealing the stress distribution and internal force changes of the novel composite joint. The failure mode, damage evolution, bearing capacity, ductility, stiffness degradation, and energy dissipation capacity of the novel reinforced composite structure under low-cycle cyclic loading were clarified. Based on the finite element analysis results, a simplified analytical model of the specimens was established, and a seismic restoring force model was proposed.

[0036] (2) Specific experimental procedures for the collapse resistance performance of the new reinforced composite structure: Design and fabricate four composite substructure specimens, as shown in the attached document. Figure 3 As shown in (c)-(f), the test included traditional nodes with two different node connection methods and a novel reinforced composite node. The test employed a quasi-static unidirectional loading method until specimen failure. The deformation patterns and failure modes of different types of specimens from loading to failure were compared. The strain variation trends in the node region and the support constraint region were analyzed. The development patterns of bending and catenary effects of different nodes were obtained through comparison, particularly the relationship between the rotational capacity of the novel node and the degree of catenary effect development.

[0037] Based on the finite element software ABAQUS, refined finite element models of each specimen were established. Numerical models were used to analyze the stress distribution and internal force variations of the novel composite joint, investigating the stress characteristics of the joint region during elastic and plastic deformation stages, focusing on the mechanisms of bending and catenary effects. The damage and fracture evolution process was reproduced using numerical simulation, extracting the stress distribution of the flange and web sections at different stress stages, with a focus on analyzing the fracture occurrence patterns and revealing the fracture failure patterns induced by different parameters. Furthermore, based on the damage evolution and failure modes of the novel ductile joint under different parameters, the damage accumulation law of the beam-column joint was revealed, and qualitative descriptions and quantitative indicators of different damage states were determined. Based on the ultimate deformation and cumulative deformation energy dissipation of the beam-column substructure, a failure criterion for the novel ductile joint considering the catenary effect was established.

[0038] Combining experimental results and a refined finite element model, the occurrence and propagation of cracks, the degree of damage and corresponding deformation, and the relationship between the height of the plastic hinge zone and the section rotation angle at each stage under vertical load were recorded in detail. The bearing capacity and deformation capacity of the beam-column substructure under different parameters, the joint failure mode and force transmission characteristics, and the evolution process of bending mechanism and suspension mechanism were obtained. Based on the ultimate deformation and ultimate bearing capacity of the member under the vertical load of the central column, the influence of each parameter on the bearing capacity, failure mechanism, shear deformation of the joint core area, and energy consumption of the joint substructure were systematically analyzed, and a reasonable range of bending parameters for corrugated steel plates was suggested.

[0039] (3) Specific experimental procedures for the anti-collapse stress performance of the new reinforced composite structure after earthquake damage: Design and fabricate 6 composite substructure specimens, as shown in the attached document. Figure 3 As shown in (a)-(f), three specimens of each type were used. To determine different degrees of seismic damage, a force-displacement loading regime was adopted, with loading degrees set at 1.2, 1.5, and 1.8 times the yield displacement, respectively. The energy dissipation and bearing capacity parameters of the nodes under different loading states were recorded. Based on the seismic test results, reasonable seismic damage evaluation indicators and degrees of damage were formulated. Then, the six damaged specimens underwent progressive collapse resistance tests using a unidirectional loading method until specimen failure, recording parameters such as ultimate displacement and bearing capacity. The deformation patterns and failure modes of each specimen from loading to failure were compared, and the strain change trends in the node region and support constraint region were analyzed. The development laws of node bending effect and catenary effect under different seismic damage states were obtained through comparison. Combining quantitative indicators such as yield load, yield displacement, ultimate bearing capacity, stiffness degradation, ductility, and energy dissipation capacity under seismic loading, a new reinforced composite node seismic damage assessment model was established.

[0040] Based on the finite element software ABAQUS, this study uses numerical simulation to reproduce the damage and fracture evolution process after earthquake damage, revealing the damage accumulation law caused by uneven loads on beam-column joints under earthquake and collapse actions, and establishing a new failure criterion for reinforced composite structures oriented towards earthquake-collapse. Combining experimental results and a refined finite element model, the study obtains the bearing capacity and deformation capacity, joint failure modes and force transmission characteristics of reinforced composite structures under different parameters, as well as the evolution process of bending and suspension mechanisms. The study systematically analyzes the influence of various parameters on the bearing capacity, failure mechanism, shear deformation of the joint core area, and energy dissipation of joint substructures, elucidating the development law of the anti-collapse performance of reinforced composite structures after earthquake damage under multi-parameter variation conditions. Based on the above analysis results, a method for calculating the anti-collapse bearing capacity after earthquake damage is proposed, and a comprehensive risk assessment system oriented towards earthquake-collapse is established.

[0041] The experimental methods used in this embodiment include: (1) The tensile test of the structural steel was carried out using a microcomputer-controlled electro-hydraulic servo universal testing machine. The maximum load of the universal testing machine was 1000kN and the accuracy was ±5kN.

[0042] (2) The seismic resistance study of the new reinforced composite structure adopts the microcomputer-controlled electro-hydraulic servo MTS loading system for quasi-static loading.

[0043] (3) Research on the anti-collapse performance of the new reinforced composite structure: a microcomputer-controlled electro-hydraulic servo MTS loading system was used for unidirectional axial loading.

[0044] Ultimately, this embodiment, through a combination of theoretical analysis, numerical simulation, and experimental research, constitutes a complete research system and technical route. The seismic performance and collapse resistance studies of the specimens respectively represent the structural development, design theory establishment, and seismic and collapse resistance performance research of the novel reinforced beam-column composite structural system, laying the foundation for subsequent research on the post-earthquake collapse resistance of the novel reinforced composite structure. The research methods, technical routes, and logical relationships between the sub-topics are as follows: Figure 4 As shown.

[0045] Based on the above research, a specific implementation method is provided: In this embodiment, the Pushdown static loading method is used to apply a concentrated load to the top of the column of the specimen. The loading process is divided into two stages: (1) When the specimen is in the elastic stage, the specimen is loaded with a force control method of 5kN / min until the specimen yields; (2) After the specimen yields, the substructure specimen is loaded with a constant displacement loading method of 5mm / min until the loading stops when the following situations occur: (1) the node substructure is severely damaged; (2) the load value or displacement value of the specimen is about to exceed the range; (3) the situation that causes harm to the test instrument may lead to potential safety hazards.

[0046] The main measurement objectives of this experiment are as follows: (1) to measure the overall deflection deformation of the specimen along the beam span direction; (2) to measure the load and displacement at the top of the column of the specimen; and (3) to determine the strain distribution and internal force of the key section of the specimen.

[0047] In this experiment, the displacement gauges of all structural specimens were arranged in the same way. Taking the corrugated steel plate reinforced bolted and welded hybrid joint specimen (CSR-BW type specimen) as an example, in order to monitor the deformation of the substructure specimen during loading, eight vertical displacement sensors were symmetrically placed along the beam length at the flange position of each specimen, which were denoted as D1-D8. At the same time, two horizontal sensors were placed on both sides of the beam end support to monitor the lateral displacement.

[0048] In this experiment, to calculate the internal forces of the substructure specimens during the test and to analyze the resistance mechanism of the specimens during the progressive collapse process, five strain gauges were arranged at each of the L1-L1 (R1-R1) sections near the end beam supports, which were expected to be in an elastic state during the failure of the central column, to calculate the internal forces of the sections. Simultaneously, to monitor the formation of plastic hinges in the sections, a total of 26 strain gauges were arranged at the L2-L2 (R2-R2), L3-L3 (R3-R3), and L4-L4 (R4-R4) sections to monitor strain development and stress changes in these areas. In addition to the above sections, to investigate the effect of the corrugated steel plate as a second force transmission path and its secondary defense during the large deformation stage, a total of 20 transverse strain gauges were arranged on the corrugated plate.

[0049] Test results of the collapse resistance of corrugated steel plate reinforced composite joints under different seismic damage conditions: First, determine the failure characteristics of the specimen.

[0050] (1) Specimen CSR-B-0 Specimen CSR-B-0 is a corrugated steel plate reinforced with bolted connections and was not subjected to seismic damage treatment (quasi-static test). In the initial stage of the test, the loading device gradually came into close contact with the specimen, emitting a "clunking" sound during loading, but without significant flexural deformation; the load-displacement curve showed some fluctuations. When the displacement reached 44.24 mm (corresponding to a load of 30.92 kN), the force transmission path of the specimen stabilized, entering the elastic stress stage. As the displacement of the central column increased, slight flexural deformation occurred in the beam segments on both sides of the central column. The upper and lower flanges of the two side sections remained intact; the upper flange connection was tightly fitted without gaps, while the lower flange connection was gradually pulled apart, but the connecting plate did not buckle. The specimen was in a typical bending deformation stress stage. When the displacement reached 94.19 mm (corresponding to a load of 107.74 kN), a crack appeared in the lower flange connecting plate on the N side. As the displacement of the central column continued to increase, the specimen produced a loud "bang," and all four bolts on the left side of the lower flange on the N side sheared off. The crack in the lower flange connecting plate gradually extended until it completely tore open. Due to the fracture of the lower flange of the beam on the N side, the entire model gradually tilted towards the N side, causing the crack to accelerate from the shear plate towards the top area of ​​the bolt holes. The load-displacement curve of the specimen continued to rise, and the vertical bearing capacity gradually increased from 43.64 kN to 56.11 kN. At the same time, the corrugated steel plate began to extend from a displacement of 123.12 mm (corresponding to a load of 43.64 kN), and the bolt holes in the web began to deform, with obvious tearing of the steel plate. Subsequently, with continued loading, the web cracks propagated towards the upper flange, and the crack width continued to increase, gradually straightening the corrugated steel plate. When the displacement reached 161.9 mm (corresponding to a load of 54.64 kN), the corrugated steel plate straightened and its deformation decreased, becoming the main load-bearing component. The specimen's load-bearing capacity rapidly increased from 55.65 kN to 161.69 kN (corresponding to a displacement of 253.23 mm), and the load-displacement curve reached its second peak. Then, with another loud bang, the four bolts on the left side of the upper flange on the N side sheared simultaneously, and the load-bearing capacity plummeted to 102.12 kN. At this point, only the corrugated steel plate connecting the lower flange continued to bear the load. When the displacement reached 257.06 mm (corresponding to a load of 126.22 kN), the corrugated steel plate also fractured, and the N-side beam segment lost its load-bearing capacity.

[0051] (2) Specimen CSR-B-60 Specimen CSR-B-60 is a corrugated steel plate reinforced with bolted joints and has undergone seismic damage treatment (quasi-static test loading to 60mm). In the initial stage of the test, the loading device gradually came into close contact with the specimen, emitting a "clunking" sound during loading, but without significant flexural deformation; the load-displacement curve showed some fluctuations. When the load reached 54.5mm (corresponding to a load of 12kN), the specimen's force transmission path stabilized, entering the elastic stress stage. As the displacement of the central column increased, slight flexural deformation occurred in the beam segments on both sides of the central column. The upper and lower flanges of the two side sections remained intact; the upper flange connection was tightly fitted without gaps, while the lower flange connection gradually opened, but the connecting plate did not buckle. The specimen was in a typical bending deformation stress stage. When the displacement reached 86.6 mm (corresponding to a load of 90 kN), the specimen exhibited a loud "bang," and two bolts on the right side of the lower flange on the S side sheared off, reducing the load-bearing capacity to 50.6 kN. When the displacement continued to 99.8 mm, the remaining two bolts on the right side of the lower flange on the S side also sheared off, reducing the load-bearing capacity from 62.9 kN to 47.7 kN. Without bolt restraint, the connecting steel plates of the lower flange warped. Due to the fracture of the lower flange of the beam on the S side, the entire model gradually tilted towards the S side, and the bolt holes in the web and the corrugated steel plate simultaneously began to deform. Deformation began to appear in the bolt holes at the web, and the steel plate showed obvious tearing. The cracks accelerated from the shear plate towards the top of the bolt holes, and the load-displacement curve began to rise to 59.5 kN (corresponding to a displacement of 113.4 mm). Subsequently, as the central column continued to displace downwards, cracks began to appear in the connecting plate of the lower flange on the S side until it completely separated, and the load-bearing capacity dropped again to 31.7 kN. The corrugated steel plate extended towards both ends, from a displacement of 125.17 mm to 179.7 mm. The load-displacement curve of the specimen began to rise, and the vertical bearing capacity gradually increased from 31.7 kN to 45.6 kN. With continued loading, the web cracks propagated towards the upper flange, and the crack width increased continuously. The corrugated steel plate gradually straightened and its deformation decreased, becoming the main load-bearing component. The specimen's bearing capacity rapidly increased from 45.6 kN to 153.5 kN (corresponding to a displacement of 267.9 mm), and the load-displacement curve reached its second peak. Then, with another loud bang, the specimen's bearing capacity plummeted from 153.5 kN to 18.8 kN. Four bolts on the left side of the upper flange on the S side sheared simultaneously, and the corrugated steel plate connection also broke, causing the S-side beam segment to lose its load-bearing capacity.

[0052] (3) Specimen CSR-B-70 Specimen CSR-B-70 is a corrugated steel plate reinforced with bolted joints and has undergone seismic damage treatment (quasi-static test loading to 70mm). In the initial stage of the test, the loading device gradually came into close contact with the specimen, emitting a "clunking" sound during loading, but without significant flexural deformation; the load-displacement curve showed some fluctuations. When the displacement reached 38.41mm (corresponding to a load of 16.4kN), the specimen's force transmission path stabilized, entering the elastic stress stage. As the displacement of the central column increased, slight flexural deformation occurred in the beam segments on both sides of the central column. The upper and lower flanges of both sides remained intact; the upper flange connection was tightly fitted without gaps, while the lower flange connection gradually opened, but the connecting plate did not buckle. The specimen was in a typical bending deformation stress stage. When the displacement reached 74.1mm (corresponding to a load of 93.4kN), the specimen emitted a loud "bang," and two bolts on the right side of the lower flange on side S sheared off, reducing the bearing capacity to 36.9kN. Due to the fracture of the lower flange of the beam on side S, the entire model gradually tilted towards side S, and the bolt holes in the web and the corrugated steel plate simultaneously began to deform. Deformation began to appear in the bolt holes in the web, and the steel plate showed obvious tearing, with cracks extending rapidly from the shear plate towards the top of the bolt holes. When the displacement continued to 100.54 mm (corresponding to a load of 49.5 kN), cracks began to appear in the connecting plate of the lower flange on side S until it completely separated, and the bearing capacity subsequently decreased again to 23.29 kN. The corrugated steel plate extended towards both ends, from a displacement of 104.89 mm to 163.94 mm. The load-displacement curve of the specimen began to recover, and the vertical bearing capacity gradually increased from 23.29 kN to 43.22 kN. As loading continued, the web cracks propagated towards the upper flange, and the crack width increased continuously. The corrugated steel plate was gradually straightened and its deformation decreased, becoming the main load-bearing component. The specimen's load-bearing capacity rapidly increased from 43.22 kN to 147.14 kN (corresponding to a displacement of 239.27 mm), and the load-displacement curve reached its second peak. Then, with another loud bang, the four bolts on the right side of the upper flange on the S side sheared simultaneously, and the load-bearing capacity plummeted to 94.39 kN. At this point, only the corrugated steel plate connecting the lower flange continued to bear the load. When the displacement reached 243.66 mm (corresponding to a load value of 114.82 kN), the corrugated steel plate also fractured, and the S-side beam segment lost its load-bearing capacity.

[0053] (4) Specimen CSR-B-80 Specimen CSR-B-80 is a corrugated steel plate reinforced with bolted joints and has undergone seismic damage treatment (quasi-static test loading to 80mm). In the initial stage of the test, the loading device gradually came into close contact with the specimen, emitting a "clunking" sound during loading, but without significant flexural deformation; the load-displacement curve showed some fluctuations. When the load reached 38.23mm (corresponding to a load of 10.53kN), the force transmission path of the specimen stabilized, entering the elastic stress stage. As the displacement of the central column increased, slight flexural deformation occurred in the beam segments on both sides of the central column. The upper and lower flanges of the two side sections remained intact; the upper flange connection was tightly fitted without gaps, while the lower flange connection was gradually pulled apart, but the connecting plate did not buckle. The specimen was in a typical bending deformation stress stage. When the displacement reached 93.73 mm (corresponding to a load of 89.34 kN), the specimen exhibited a loud "bang," and four bolts on the left side of the lower flange on the N side sheared off, reducing the bearing capacity to 47.78 kN. Without bolt restraint, the connecting steel plates of the lower flange warped and came into contact with the corrugated steel plate. Due to the fracture of the lower flange of the beam on the N side, the entire model gradually tilted towards the N side, and the bolt holes in the web and the corrugated steel plate simultaneously began to deform. At this point, the bolt holes in the web began to deform, and the corrugated steel plate extended to both ends, from a displacement of 134.95 mm to 174.87 mm. The load-displacement curve of the specimen began to recover, and the vertical bearing capacity gradually increased from 33.14 kN to 48.58 kN. As loading continued, the corrugated steel plate gradually straightened and its deformation decreased, initially acting as the primary load-bearing component. However, when the displacement increased to 181.8 mm (corresponding to a load of 62.74 kN), one side of the corrugated steel plate on the lower flange of the N-side suddenly fractured, and the specimen's load-bearing capacity dropped to 55.11 kN. Subsequently, when the displacement was increased to 189.44 mm, the corrugated steel plate on the other side also fractured, and the load-bearing capacity decreased from 74.44 kN to 63.84 kN. With continued loading, cracks appeared near the bolt holes in the web and propagated upwards towards the flange, increasing the load-bearing capacity from 63.84 kN to 104.84 kN (corresponding to a displacement of 240.73 mm), and the load-displacement curve reached its second peak. Then, with another loud bang, the specimen's load-bearing capacity plummeted from 104.84 kN to 45.96 kN. Four bolts on the left side of the upper flange on the N side were sheared simultaneously, and the corrugated steel plate connection also broke, causing the S side beam segment to lose its load-bearing capacity.

[0054] (5) Specimen CSR-BF The CSR-BF specimen features a corrugated steel plate reinforced with bolted connections. After earthquake damage treatment, the flanges fractured, and the flange connection plates exhibited warping. In the initial stage of the test, the loading device gradually came into close contact with the specimen, producing a "clunking" sound during loading, and the load-displacement curve showed some fluctuations. Initially, the applied load produced a large displacement, reaching 49.3 mm (corresponding to a load value of 16.27 kN), at which point the force transmission path of the specimen stabilized, entering the elastic stress stage. As the displacement of the central column increased, the upper flange connections moved closer together, but a certain gap remained, while the lower flange connections gradually separated, and the specimen entered a typical bending deformation stress stage. Furthermore, deformation began to appear in the bolt holes at the web, with cracks extending rapidly from the shear plate towards the top of the bolt holes, and the corrugated steel plate also extending towards both ends. When the displacement reached 109.85 mm (corresponding to a load of 61.97 kN), the specimen exhibited a loud "bang," and the lower flange connecting plate on the S-side back fractured, reducing the load-bearing capacity to 33.76 kN. As loading continued, the steel plate showed obvious tearing, with cracks extending horizontally towards the central column after reaching the upper flange. When the displacement reached 152.33 mm, the corrugated steel plate straightened and its deformation decreased, becoming the primary load-bearing component, and its load-bearing capacity rapidly increased from 37.52 kN to 101.41 kN (corresponding to a displacement of 218.74 mm). The load-displacement curve reached its second peak. Then, with another sharp crack, the corrugated steel plate connection fractured, and the S-side beam segment lost its load-bearing capacity.

[0055] (6) Specimen CSR-BW-0 Specimen CSR-BW-0 is a corrugated steel plate reinforced with a bolted and welded hybrid joint, and has not undergone seismic damage treatment (quasi-static loading test). In the initial stage of the test, the loading device gradually brought the specimen into close contact. The specimen was in the elastic stage with no obvious flexural deformation, and the load-displacement curve was smooth. When the displacement reached 31.67 mm (corresponding to a load of 83.42 kN), the specimen entered the elastoplastic stage. As the displacement of the central column increased, slight flexural deformation occurred in the beam segments on both sides of the central column. The upper and lower flanges of the two side sections remained intact, and the specimen was in a typical bending deformation stress stage. When the displacement reached 88.74 mm (corresponding to a load of 110.88 kN), the specimen exhibited a loud "bang," and the lower flange on the N side fractured, reducing the bearing capacity to 24.78 kN. Due to the fracture of the lower flange of the N-side beam, the entire model gradually tilted towards the N side, and the web bolt holes and corrugated steel plate simultaneously began to deform. When the loaded displacement increased from 92.72 mm to 131.69 mm, the load-displacement curve of the specimen began to rise, and the vertical bearing capacity gradually increased from 24.78 kN to 61.4 kN. With continued loading, the web crack reached the upper flange and extended horizontally towards the central column, with the crack width continuously increasing. The resistance provided by the bolted connection area between the shear plate and the web decreased, and the specimen's bearing capacity showed a downward trend, decreasing from 61.4 kN to 46.65 kN (corresponding to a loaded displacement of 142.07 mm). Subsequently, the corrugated steel plate gradually straightened and its deformation decreased, becoming the main load-bearing component. The specimen's bearing capacity rapidly increased from 46.65 kN to 180.22 kN (corresponding to a displacement of 269.03 mm), and the load-displacement curve reached its second peak. Then, with another loud "bang," the corrugated steel plate on the front of the lower flange of the N side fractured, and the load-bearing capacity dropped to 150.18 kN. When the load was increased to 292.8 mm, the corrugated steel plate on the back of the lower flange of the N side fractured, and the load dropped sharply from 163.04 kN. The N side beam segment lost its load-bearing capacity.

[0056] (7) Specimen CSR-BW-30 Specimen CSR-BW-30 is a corrugated steel plate reinforced with a bolted-welded hybrid joint and has undergone seismic damage treatment (quasi-static loading to 30 mm). In the initial stage of the test, the loading device gradually brought the specimen into close contact with the specimen. The specimen was in the elastic stage with no obvious flexural deformation, and the load-displacement curve was smooth. When the displacement reached 15.82 mm (corresponding to a load of 66.4 kN), the specimen entered the elastoplastic stage. As the displacement of the central column increased, slight flexural deformation occurred in the beam segments on both sides of the central column. The upper and lower flanges of the two side sections remained intact, and the specimen was in a typical bending deformation stress stage. When the displacement reached 37.1 mm (corresponding to a load of 88.69 kN), the specimen exhibited a loud "bang," and the lower flange on the N side fractured, reducing the bearing capacity to 15.07 kN. Due to the fracture of the lower flange of the N-side beam, the entire model gradually tilted towards the N side, and the web bolt holes and corrugated steel plate simultaneously began to deform. When the loaded displacement increased from 37.7 mm to 71.28 mm, the load-displacement curve of the specimen began to rise, and the vertical bearing capacity gradually increased from 15.07 kN to 35.79 kN. With continued loading, the web crack reached the upper flange and extended horizontally towards the central column, with the crack width continuously increasing. The resistance provided by the bolted connection area between the shear plate and the web decreased, and the specimen's bearing capacity showed a fluctuating downward trend, decreasing from 35.79 kN to 19.48 kN (corresponding to a loaded displacement of 157.69 mm). Subsequently, the corrugated steel plate gradually straightened and its deformation decreased, becoming the main load-bearing component. The specimen's bearing capacity rapidly increased from 19.48 kN to 174.79 kN (corresponding to a loaded displacement of 276.93 mm), and the load-displacement curve reached its second peak. Then, with another loud "bang," the corrugated steel plate on the front of the lower flange of the N side fractured, and the load-bearing capacity dropped to 151.41 kN. When the load was increased to 285.54 mm, the corrugated steel plate on the back of the lower flange of the N side fractured, and the load dropped sharply from 165.3 kN, and the N side beam segment lost its load-bearing capacity.

[0057] (8) Specimen CSR-BW-36 Specimen CSR-BW-36 is a corrugated steel plate reinforced with a bolted-welded hybrid joint and has undergone seismic damage treatment (quasi-static loading to 36 mm). In the initial stage of the test, the loading device gradually brought the specimen into close contact with the specimen. The specimen was in the elastic stage with no obvious flexural deformation, and the load-displacement curve was smooth. When the displacement reached 15.33 mm (corresponding to a load of 67.55 kN), the specimen entered the elastoplastic stage. As the displacement of the central column increased, slight flexural deformation occurred in the beam segments on both sides of the central column. The upper and lower flanges of the two side sections remained intact, and the specimen was in a typical bending deformation stress stage. When the displacement reached 30.1 mm (corresponding to a load of 90.61 kN), the specimen exhibited a loud "bang," and the lower flange on the N side fractured, reducing the bearing capacity to 17.58 kN. Due to the fracture of the lower flange of the N-side beam, the entire model gradually tilted towards the N side, and the web bolt holes and corrugated steel plate simultaneously began to deform. When the loaded displacement increased from 32.65 mm to 89.01 mm, the load-displacement curve of the specimen began to rise, and the vertical bearing capacity gradually increased from 17.58 kN to 33.78 kN. With continued loading, the web crack reached the upper flange and extended horizontally towards the central column, with the crack width continuously increasing. The resistance provided by the bolted connection area between the shear plate and the web decreased, and the specimen's bearing capacity showed a fluctuating downward trend, decreasing from 33.78 kN to 16.34 kN (corresponding to a loaded displacement of 104.88 mm). Subsequently, the corrugated steel plate gradually straightened and its deformation decreased, becoming the main load-bearing component. The specimen's bearing capacity rapidly increased from 16.34 kN to 122.46 kN (corresponding to a loaded displacement of 263.22 mm), and the load-displacement curve reached its second peak. Then, with another loud "bang," the corrugated steel plate on the lower flange of the N side fractured, and the load-bearing capacity dropped to 105.9 kN. When the load was increased to 263.22 mm, the upper flange on the N side fractured, and the load dropped sharply from 122.46 kN (corresponding to a displacement of 263.22 mm), and the beam segment on the N side lost its load-bearing capacity.

[0058] (9) Specimen CSR-BW-42 Specimen CSR-BW-42 is a corrugated steel plate reinforced with a bolted-welded hybrid joint, and has undergone seismic damage treatment (quasi-static loading to 42 mm). In the initial stage of the test, the loading device gradually brought the specimen into close contact. The specimen remained in the elastic stage without significant flexural deformation, and the load-displacement curve was smooth. When the displacement reached 9.54 mm (corresponding to a load of 26.14 kN), the specimen entered the elastoplastic stage. As the loaded displacement increased from 19.75 mm to 151.92 mm, the corrugated steel plate gradually straightened and deformed, becoming the primary load-bearing component, although the load had not yet shown a significant increase. When the displacement reached 250.35 mm (corresponding to a load of 100.26 kN), the deformation of the corrugated steel plate decreased, and it began to bear the load. Minor cracks appeared at the connection between the S-shaped side beam and the central column. Then, as loading continued, with another loud "bang," the corrugated steel plate on the lower flange of the S side fractured, and the load-bearing capacity dropped from 131.16kN (corresponding to a loading displacement of 255.86mm) to 108.7kN, and the S side beam segment lost its load-bearing capacity.

[0059] (10) Specimen CSR-BW-F The specimen CSR-BW-F is a corrugated steel plate reinforced with a bolted and welded hybrid joint, and its flange fracture occurred after a quasi-static loading test. In the initial stage of the test, the loading device gradually came into close contact with the specimen, which was in an elastic phase, with the upper flange under compression and the lower flange under tension separation, resulting in a smooth load-displacement curve. Due to the fracture of the lower flange of the beam on side S, the entire model gradually tilted towards side S, and the web bolt holes and corrugated steel plate simultaneously began to deform. When the loaded displacement reached 29.54 mm, the specimen's load-displacement curve rose, and the vertical bearing capacity gradually increased to 23.39 kN. Subsequent loading caused the web crack to extend horizontally towards the central column from the upper flange, and the crack width continuously increased. The resistance provided by the shear plate and the bolted connection area of ​​the web decreased, and the specimen's bearing capacity showed a fluctuating downward trend, decreasing to 9.74 kN (corresponding to a loaded displacement of 167.1 mm). The corrugated steel plate was then gradually straightened and its deformation decreased, becoming the main load-bearing component. The specimen's load-bearing capacity rapidly increased to 103.59 kN (corresponding to a loading displacement of 229 mm). With continued loading, another loud bang was heard as the corrugated steel plate on the front of the lower flange on side S fractured, and the load-bearing capacity dropped from 103.59 kN to 45.84 kN. When the loading reached 247.1 mm, the corrugated steel plate on the back of the lower flange on side S fractured, with a sudden drop in load from 72.29 kN (corresponding to a displacement of 247.1 mm), and the beam segment on side N lost its load-bearing capacity.

[0060] Then, determine the load-displacement curve.

[0061] To better summarize the load-displacement curve patterns of the above test specimens, specimens CSR-B-70 and CSR-BW-30 were selected as typical load-displacement curves. Based on the test results of the corrugated steel plate reinforced bolt connection joint, the overall test process can be divided into 7 stages. The specific descriptions of each stage are as follows: Phase I: This phase is the specimen slippage phase. Due to the quasi-static test and the bolt connection, there will be a certain bolt hole clearance. In this phase, a large displacement will often occur under a small load.

[0062] Phase II: The specimen is in the elastic stage and no obvious flexural deformation has occurred.

[0063] Stage III: The specimen enters the elastoplastic stage, and localized yielding occurs in the flange connection plate of the specimen.

[0064] Stage IV: The connecting bolts on the lower flange of the specimen shear off, causing a rapid drop in load-bearing capacity. During this stage, tearing of the connecting plate may also occur. Therefore, the load-bearing capacity decrease is not necessarily vertical; a stepped decrease may occur, but the loaded displacements are usually not significantly different. At this point, the specimen begins to deform considerably. The bolts on the web begin to compress the borehole wall and deform. Tearing of the borehole wall is clearly visible at the web, with cracks protruding towards the upper flange. The corrugated plate also begins to elongate.

[0065] Phase V: Cracks in the web reach the bottom of the upper flange and extend horizontally towards the central column. Simultaneously, the corrugated plate continues to stretch until it reaches its load-bearing length.

[0066] Stage VI: The deformation of the corrugated steel plate decreases as it enters the stress stage, and the bearing capacity of the specimen begins to rise and exceeds the first peak bearing capacity.

[0067] Stage VII: The corrugated steel plate on the lower flange of the specimen fractures, and then, as the loading continues, the bolts on the upper flange will also shear off.

[0068] Based on the test results of the corrugated steel plate reinforced bolted-welded hybrid joint, the overall test process can be divided into 6 stages, each described in detail below: Phase I: The specimen is in the elastic stage and no obvious flexural deformation has occurred.

[0069] Stage II: The specimen enters the elastoplastic stage, and yielding occurs at the upper and lower flanges.

[0070] Stage III: The lower flange of the specimen fractures, and the load-bearing capacity drops rapidly. At this point, the specimen begins to deform significantly. The bolts on the web begin to compress the borehole wall and deform. Tearing of the borehole wall can be clearly observed at the web, and the cracks propagate towards the upper flange. The corrugated plate also begins to elongate.

[0071] Stage IV: Cracks in the web reach the bottom of the upper flange and extend horizontally towards the central column. Simultaneously, the corrugated plate continues to stretch until it reaches its load-bearing length.

[0072] Phase V: The deformation of the corrugated steel plate decreases as it enters the stress stage, and the bearing capacity of the specimen begins to rise and exceeds the first peak bearing capacity.

[0073] Stage VI: The corrugated steel plate on the lower flange of the specimen fractures, and then the upper flange may also fracture as the loading continues.

[0074] Comparing the mechanical properties of corrugated steel plate reinforced bolted connections and corrugated steel plate reinforced bolt-welded hybrid connections under different vibration damage conditions, it is easy to see that the mechanical properties of the specimens decrease significantly with the increase of quasi-static loading. It is worth noting that the lower flanges of specimens CSR-BF and CSR-BW-F were already in a state of failure before the collapse test; therefore, the lower flange failure column is not reflected in the data table.

[0075] Table 1 shows that: (1) Under the condition of vibration damage, the first peak value of the corrugated steel plate reinforced bolt connection node decreased by a maximum of 44.26%, and the second peak value decreased by a maximum of 37.28%. The bearing capacity of the corrugated steel plate reinforced bolt connection node decreased with the increase of vibration damage, with a reduction range of 5.07% to 37.28%. (2) The first peak displacement of the specimen decreased by a maximum of 21.33%, and the second peak displacement decreased by a maximum of 13.62%. The ductility of the corrugated steel plate reinforced bolt connection node decreased with the increase of vibration damage, with a reduction range of -5.79% to 13.62%. (3) With the increase of vibration damage, the effective load of the corrugated steel plate decreased, with a reduction range of 11.09% to 31.33%.

[0076] Table 1

[0077] Table 2

[0078] Table 2 shows that (1) the first peak value of the corrugated steel plate reinforced bolted-welded connection joint decreased by a maximum of 78.91% and the second peak value decreased by a maximum of 42.52% under the seismic damage condition. The bearing capacity of the corrugated steel plate reinforced bolted-welded connection joint decreased with the increase of the seismic damage degree, with a reduction range of 3.01%~42.52%. (2) The first peak displacement of the specimen decreased by a maximum of 75.81% and the second peak displacement decreased by a maximum of 14.88%. The ductility of the corrugated steel plate reinforced bolted-welded connection joint decreased significantly due to seismic damage, with a reduction range of 4.08%~21.79%. (3) With the increase of the seismic damage degree, the effective load of the corrugated steel plate decreased, with a reduction range of 64.35%~82.17%.

[0079] This embodiment has the following beneficial effects: (1) The stress mechanism and working mechanism of the new reinforced composite structure during the earthquake resistance process, the working mechanism of corrugated plate and steel beam, and the establishment of the earthquake resistance design theory of the new reinforced composite node.

[0080] (2) The load-displacement relationship of the new reinforced composite structure from the bending stage to the catenary stage during the process of resisting progressive collapse reflects the development law of catenary effect and the corresponding node deformation law, and establishes the new reinforced composite node anti-collapse design theory.

[0081] (3) Whether the new reinforced structure can form an effective alternative force transmission path under the secondary disaster of the removal of the central column after the earthquake. By comparing the collapse resistance performance of the substructure under no earthquake damage and different earthquake damage, the seismic damage coefficient of the reinforced composite node related to the connection method is proposed, and it is fitted with the key dimensionless parameters of the structure to extract the calculation formula of the collapse resistance capacity of the new reinforced composite structure under different earthquake damage.

[0082] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0083] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for evaluating the post-earthquake collapse resistance of a corrugated steel plate reinforced composite structure, applied to corrugated steel plate reinforced composite structures, characterized in that: The corrugated steel plate reinforced composite structure includes: an H-beam assembly, a square steel tube, and multiple corrugated steel plates; the H-beam assembly includes multiple H-beams connected in sequence; one end of the H-beam assembly is fixedly connected to one side of the square steel tube; the H-beams are fixed together by a predetermined beam-column joint connection method; two corrugated steel plates are provided at the beam-column joint connection position of every two H-beams; the beam-column joint connection method adopts bolted connection or bolted-welded hybrid connection; the bolted connection is: the top, middle, and bottom of each H-beam are fixed together by bolts; the bolted-welded hybrid connection is: the top and bottom of each H-beam are fixed together by welding; the middle of each H-beam is fixed together by bolts. The method for assessing post-earthquake collapse resistance includes: The corrugated steel plate reinforced composite structure was fixed on the experimental device, and low-cycle repeated loading was applied according to the procedures specified in the AISC seismic code to determine the collaborative seismic data of the corrugated steel plate reinforced composite structure. The collaborative seismic data included: failure mode, damage evolution, bearing capacity, ductility, stiffness degradation, and energy dissipation capacity. A seismic resilience model is constructed based on the aforementioned collaborative seismic resistance data; By using the quasi-static unidirectional loading method until the specimen of the corrugated steel plate reinforced composite structure fails, the load-displacement relationship is determined through the development law of bending effect and catenary effect at different nodes; Establish a node failure criterion based on the load-displacement relationship; Using a force-displacement loading regime and a progressive collapse-resistant loading method, the specimens of the corrugated steel plate reinforced composite structure were loaded, and the nodal energy dissipation and bearing capacity parameters under different loading states were recorded. Based on the seismic test results, seismic damage evaluation indicators and seismic damage degree were formulated. The progressive collapse-resistant loading method includes the column removal method and the instantaneous failure method of the middle column. Based on the seismic resilience model, the node failure criterion, the seismic damage evaluation index, and the degree of seismic damage, a comprehensive risk assessment system oriented towards earthquake-collapse is constructed, and the post-earthquake collapse resistance performance is evaluated using the comprehensive risk assessment system oriented towards earthquake-collapse.

2. The method for evaluating post-earthquake collapse resistance according to claim 1, characterized in that, The method for determining the collaborative seismic resistance data is as follows: The corrugated steel plate reinforced composite structure was fixed on the experimental device, and low-cycle cyclic loading was applied according to the procedures specified in the AISC seismic code. Finite element models of specimens with different beam-column joint connection methods were established using the finite element software ABAQUS, and the numerical model was verified by actual test results. Then, the influence of the key parameters of the corrugated steel plate on the seismic performance of the specimens was tested to obtain the stress distribution and internal force changes of the corrugated steel plate reinforced composite structure, as well as the synergistic seismic data under low-cycle cyclic loading.

3. The method for evaluating post-earthquake collapse resistance according to claim 1, characterized in that, The establishment of nodal failure criteria based on the load-displacement relationship specifically includes: Using the finite element software ABAQUS and the load-displacement relationship, finite element models of specimens with different beam-column joint connection methods were established. The stress distribution and internal force changes of the corrugated steel plate reinforced composite structure were analyzed by numerical model. The stress characteristics of the joint area in the elastic deformation and plastic deformation stages were studied, and the mechanism of bending effect and catenary effect was determined. The damage and fracture evolution process is reproduced by numerical simulation. The stress distribution of the flange and web sections at different stress stages is extracted, the fracture occurrence law is analyzed, and the fracture failure law caused by different parameters is obtained. Based on the damage evolution process and failure mode of the corrugated steel plate reinforced composite structure under different parameters, the damage accumulation law of beam-column joints is obtained, thereby determining the qualitative description and quantitative index of different damage states. According to the ultimate deformation and cumulative deformation energy consumption of the beam-column substructure, a new failure criterion for ductile joints considering the catenary effect is established.

4. The method for evaluating post-earthquake collapse resistance according to claim 1, characterized in that, The method for constructing the comprehensive risk assessment system oriented towards earthquake-collapse is as follows: Based on the finite element software ABAQUS, the seismic restoring force model, the node failure criterion, the seismic damage evaluation index and the degree of seismic damage, the bearing capacity and deformation capacity, node failure mode and force transmission characteristics of the reinforced composite structure under different parameters in the face of earthquake-collapse, as well as the evolution process of bending mechanism and suspension mechanism. The influence of various parameters on the substructure bearing capacity, failure mechanism, shear deformation and energy dissipation of the core area of ​​the corrugated steel plate reinforced composite structure was analyzed. The development law of the anti-collapse performance of the reinforced composite structure after earthquake damage under multi-parameter variation conditions was obtained. Based on the law analysis results and the calculation method of anti-collapse bearing capacity after earthquake damage, a comprehensive risk assessment system for earthquake-collapse was established.

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