Anti-seismic performance simulation test method and system for concrete-filled steel tube structure

Abstract

The invention relates to the technical field of computer-aided anti-seismic analysis, and discloses an anti-seismic performance simulation test method and system for a concrete-filled steel tube structure, and the method comprises the steps: obtaining a parameter set of the concrete-filled steel tube structure; identifying a critical buckling mode and constructing a defect correction model; constructing a coupling damage index; constructing a numerical instability risk evaluation value based on the structure energy proportion; carrying out strong earthquake nonlinear time-history iterative solution; and outputting the anti-seismic performance index set and the coupling failure area. Compared with the prior art, the technical problem that Newton iteration divergence is prone to occurring in numerical solution under the coupling instability condition that traditional nonlinear finite element analysis is relied on for strong earthquake response calculation, especially when a steel pipe is subjected to local buckling and core concrete enters a high-pressure three-axis stress state is solved. Due to the fact that the local buckling and crushing damage coupling index and the self-adaptive time step length adjusting mechanism are constructed, the stability of the anti-seismic performance simulation result of the concrete-filled steel tube structure under the strong earthquake effect is improved.

Description

Technical Field

[0001] This invention relates to the field of computer-aided seismic analysis technology, and in particular to a method and system for simulating and testing the seismic performance of steel-concrete composite structures. Background Technology

[0002] Currently, concrete-filled steel tube (CFST) structures are widely used in high-rise buildings, bridge structures, and seismic fortification projects due to their excellent load-bearing and ductile properties. Under strong earthquakes, CFST members typically experience highly coupled and complex nonlinear behaviors, including local buckling of the steel tube, crushing of the core concrete, interface slip, and large geometric deformation. Therefore, in engineering practice, nonlinear finite element analysis is commonly used to simulate, test, and evaluate their seismic performance.

[0003] However, existing technologies still have significant shortcomings in the coupled analysis of large deformations under strong earthquakes. For example, under conditions where local buckling of steel tubes and crushing of concrete occur simultaneously, the superposition of material nonlinearity, contact nonlinearity, and geometric nonlinearity leads to a sharp degradation of the stiffness matrix. Traditional Newton's iterative solution method is prone to convergence difficulties, iteration divergence, or extreme reduction in time step size. Furthermore, existing methods typically rely solely on residual convergence criteria or single material damage indices for step size control, lacking a mechanism for the coordinated identification of buckling precursor characteristics and crushing evolution trends. This makes it difficult to promptly determine whether the structure is approaching a coupled instability critical state, resulting in inaccurate failure stage predictions or computational interruptions. In addition, under rapid loading conditions during strong earthquakes, the ratio of kinetic energy to internal energy changes rapidly. Without establishing a stability control strategy coupled with the actual failure mechanism of the structure, relying solely on fixed time steps or simple scaling methods for numerical adjustment often fails to balance computational efficiency and stability, making it difficult to meet the needs of refined simulation and engineering evaluation of the seismic performance of steel-concrete composite structures under extreme strong earthquake conditions.

[0004] Therefore, there is an urgent need for a simulation and testing method for the seismic performance of steel-concrete composite structures that can still achieve numerical solution for stability control and accurate identification of coupled failures under the strong nonlinear conditions of local buckling of steel tubes and crushing of concrete, so as to improve the stability of numerical analysis, the accuracy of failure prediction and the reliability of engineering applications under strong earthquakes. Summary of the Invention

[0005] To address the aforementioned technical shortcomings, the purpose of this invention is to propose a method for simulating and testing the seismic performance of steel-concrete composite structures. This method aims to solve the technical problem in existing technologies that rely on traditional nonlinear finite element analysis for calculating strong earthquake responses, especially under coupled instability conditions where the steel tube experiences local buckling and the core concrete enters a high-pressure triaxial stress state, where numerical solutions are prone to Newton iteration divergence.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention provides a method for simulating and testing the seismic performance of steel-concrete composite structures.

[0007] The seismic performance simulation test method for steel-concrete composite structures includes:

[0008] Step S10: Obtain the parameter set of the steel-concrete composite structure, and perform coupled discrete modeling task based on the parameter set using a unified parametric finite element modeling mechanism to output the initial discrete model. and standardized earthquake input sequence ;

[0009] Step S20: Based on the initial discrete model A characteristic buckling mode tracking mechanism is used to perform the critical buckling identification task and output a defect correction model. ;

[0010] Step S30: Based on the defect correction model A coupling mechanism between local buckling index and concrete crushing damage index is used to perform nonlinear material pretreatment, and the coupled failure index is output. ;

[0011] Step S40: Based on coupling failure index and standardized earthquake input sequence An energy ratio-driven adaptive value stabilization control mechanism is used to perform the stabilization parameter generation task and output a set of stabilization parameters. ;

[0012] Step S50: Based on the set of stabilization parameters Coupling failure index and standardized earthquake input sequences Perform nonlinear time history iterative solution for strong earthquakes and output a set of seismic performance indices. With coupling failure region .

[0013] Preferably, in step S10, a set of parameters for the steel-concrete composite structure is obtained, and a coupled discrete modeling task is performed using a unified parametric finite element modeling mechanism based on the set of parameters to output an initial discrete model. and standardized earthquake input sequence The steps specifically include:

[0014] Step S101: Obtain the parameter set of the steel-concrete composite structure, which includes the set of geometric parameters. Material parameter set Material density parameters and earthquake input sequences Among them, the set of material parameters This includes the elastic modulus of steel, the yield strength of steel, the hardening modulus of steel, the elastic modulus of concrete, the peak compressive strength of concrete, and the peak strain of concrete.

[0015] Step S102: Based on the geometric parameter set in the parameter set of the steel-concrete composite structure and material parameter set The initial stiffness matrix is ​​constructed by assembling the stiffness matrix using the finite element method. Based on the geometric parameter set in the parameter set of concrete-filled steel tube structures. and material density parameters The mass matrix is ​​generated using a consistent mass matrix construction method. ;

[0016] Step S103: Based on the initial stiffness matrix and mass matrix The structural eigenvalue solving task is performed using a node-coupled approach, outputting the first-order angular frequency. and the first-order periodicity of the structure ;

[0017] Step S104: Based on the first-order angular frequency and the first-order periodicity of the structure The initial discrete model is constructed and output by adjusting the reaction spectrum ratio. And using the initial discrete model For earthquake input sequences Perform spectral consistency processing and output a standardized seismic input sequence. .

[0018] Preferably, in step S20, based on the initial discrete model A characteristic buckling mode tracking mechanism is used to perform the critical buckling identification task and output a defect correction model. The steps specifically include:

[0019] Step S201: Construct a geometric stiffness reference matrix under preset axial preloading conditions, based on the geometric stiffness reference matrix and the initial stiffness matrix. Eigenvalue analysis is performed, an eigenvalue set is output, and the eigenvalue set is sorted from smallest to largest. The eigenvector corresponding to the smallest positive eigenvalue is selected as the buckling mode vector.

[0020] Step S202: Normalize the buckling mode vector and output the normalized buckling mode vector; set the initial defect amplitude according to the preset steel pipe wall thickness ratio, and construct the actual buckling morphology defect function based on the initial defect amplitude and the normalized buckling mode vector, combined with the amplitude ratio mapping function.

[0021] Step S203: Superimpose the actual buckling morphological defect function onto the initial discrete model using a nodal coordinate perturbation superposition method. Output defect correction model .

[0022] Preferably, in step S202, the initial defect amplitude does not exceed 0.5 times the wall thickness of the steel pipe, and the modal amplitude normalization method is used for extreme value truncation to prevent abnormal stiffness distortion of local elements.

[0023] Preferably, in step S30, based on the defect correction model A coupling mechanism between local buckling index and concrete crushing damage index is used to perform nonlinear material pretreatment, and the coupled failure index is output. The steps specifically include:

[0024] Step S301: Obtain the yield strength and hardening modulus of the steel, and construct a plastic yield determination function based on the yield strength and hardening modulus of the steel. The plastic yield determination function is used to determine whether the steel has entered the plastic stage.

[0025] Step S302: Obtain the earthquake input sequence Using a defect correction model For earthquake input sequences Initial nonlinear response prediction processing is performed to output the unit-level equivalent strain response sequence; the plastic yield criterion function is used to perform plastic state screening processing on the unit-level equivalent strain response sequence to output the set of units that have entered the plastic stage.

[0026] Step S303: Extract the principal compressive strain response of the corresponding concrete compression zone based on the set of units that have entered the plastic stage, obtain the peak strain of the concrete, and perform proportional mapping processing on the principal compressive strain response based on the peak strain of the concrete to output the set of damage evolution degree of the concrete compression zone; extract the maximum damage value in the set of damage evolution degree of the concrete compression zone as the concrete crushing index.

[0027] Step S304: Obtain the rate of change of curvature of the steel pipe unit, and perform weighted coupling based on the rate of change of curvature of the steel pipe unit and the concrete crushing index according to preset weights, and output the coupled failure index. Coupling failure index Characterizes the degree of synergistic failure between local buckling of the steel pipe and crushing of the concrete.

[0028] Preferably, in step S40, based on the coupling failure index and standardized earthquake input sequence An energy ratio-driven adaptive value stabilization control mechanism is used to perform the stabilization parameter generation task and output a set of stabilization parameters. The steps specifically include:

[0029] Step S401: Preset the initial time step. In each initial time step, based on the standardized seismic input sequence... The incremental dynamic balance prediction method is used to obtain the structural kinetic energy and internal energy, and an energy ratio index is constructed based on the structural kinetic energy and internal energy.

[0030] Step S402: Combine the energy ratio index with the coupling failure index A linear weighted fusion method is used for collaborative fusion to form a numerical instability risk assessment value;

[0031] Step S403: Adaptively adjust the initial time step based on the numerical instability risk assessment value; when the numerical instability risk assessment value exceeds the preset first risk threshold, decrease the initial time step; when the numerical instability risk assessment value is less than or equal to the first risk threshold, increase the initial time step; finally, output the set of stable parameters that change over time. stabilization parameter set This includes time step control and stability damping adjustment.

[0032] Preferably, in step S50, based on the set of stabilization parameters... Coupling failure index and standardized earthquake input sequences Perform nonlinear time history iterative solution for strong earthquakes and output a set of seismic performance indices. With coupling failure region The steps specifically include:

[0033] Step S501: Based on the set of stabilization parameters Coupling failure index and standardized earthquake input sequences A stabilized dynamic equation is established using an improved implicit dynamics principle; in this step, a time step control term and a stability damping adjustment term are introduced.

[0034] Step S502: Based on the stabilized dynamic equation, an implicit integration algorithm is used to perform time history iteration, outputting the structural displacement response sequence and the element strain response sequence. The coupled failure index is then determined based on the structural displacement response sequence and the element strain response sequence. Perform iterative corrections and output optimized coupling failure indicators. ;

[0035] Step S503: When optimizing coupling failure indicators When the second preset risk threshold is exceeded, the steel-concrete composite structure is determined to have entered the buckling and crushing coupled failure stage. A set of seismic performance indicators is then extracted during this stage. With coupling failure region Among them, the set of seismic performance indicators This includes the rate of degradation of bearing capacity, the rate of degradation of stiffness, and residual deformation.

[0036] The present invention also provides a seismic performance simulation and testing system for steel-concrete composite structures, comprising:

[0037] The parameter modeling module is used to obtain the parameter set of the steel-concrete composite structure. Based on the parameter set, it performs coupled discrete modeling tasks using a unified parametric finite element modeling mechanism and outputs an initial discrete model. and standardized earthquake input sequence ;

[0038] The buckling recognition module is used to identify buckling based on the initial discrete model. A characteristic buckling mode tracking mechanism is used to perform the critical buckling identification task and output a defect correction model. ;

[0039] The coupling index construction module is used for defect correction models. A coupling mechanism between local buckling index and concrete crushing damage index is used to perform nonlinear material pretreatment, and the coupled failure index is output. ;

[0040] Numerical stability control module, used for coupling failure index and standardized earthquake input sequence An energy ratio-driven adaptive value stabilization control mechanism is used to perform the stabilization parameter generation task and output a set of stabilization parameters. ;

[0041] The seismic performance output module is used to output seismic performance based on the set of stabilization parameters. Coupling failure index and standardized earthquake input sequences Perform nonlinear time history iterative solution for strong earthquakes and output a set of seismic performance indices. With coupling failure region .

[0042] The present invention also provides a seismic performance simulation testing device for steel-concrete composite structures, comprising: a memory, a processor, and a seismic performance simulation testing program for steel-concrete composite structures stored in the memory and executable on the processor. When the seismic performance simulation testing program for steel-concrete composite structures is executed by the processor, a seismic performance simulation testing method for steel-concrete composite structures is implemented.

[0043] The present invention also provides a computer program product, including a seismic performance simulation test program for steel-concrete composite structures, wherein the seismic performance simulation test program for steel-concrete composite structures implements the seismic performance simulation test method for steel-concrete composite structures when executed by a processor.

[0044] The beneficial effects of this invention are as follows: By constructing a coupled failure index of local buckling index and concrete crushing damage index, and combining it with the ratio of structural kinetic energy to internal energy to form a numerical instability risk assessment value, this invention can identify numerical instability trends in advance at the critical stage of the coordinated development of local buckling of steel tube and core concrete crushing. Furthermore, by using a dynamic adjustment mechanism of adaptive time step and stability damping parameters to reconstruct the solution path in real time, this invention effectively avoids the problems of Newton iteration divergence, sudden stiffness drop causing calculation interruption or false convergence in traditional finite element analysis under strong earthquake and large deformation conditions, and significantly improves the stability and continuity of simulation calculation under strong earthquake conditions.

[0045] This invention constructs a defect correction model consistent with the actual buckling morphology through a characteristic buckling mode tracking mechanism. During time history analysis, it weights and couples the rate of change of steel pipe curvature with the degree of damage evolution in the concrete compression zone, forming a coupled failure index reflecting the degree of synergistic failure. This achieves a quantitative characterization of the synergistic development of local buckling and concrete crushing. Compared to existing methods that rely solely on constitutive degradation of a single material or a single buckling criterion, this invention can more accurately identify coupled failure regions and bearing capacity degradation processes, improving the reliability and engineering application value of seismic performance index extraction. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0047] Figure 1 This is a flowchart illustrating the first embodiment of a seismic performance simulation test method for steel-concrete composite structures according to the present invention.

[0048] Figure 2 This is a schematic diagram showing the discrete representation of the steel pipe region and the core concrete region in the first embodiment of the seismic performance simulation test method for steel-concrete composite structures according to the present invention.

[0049] Figure 3 This is a schematic diagram illustrating the time-domain seismic input standardization effect of a first embodiment of the seismic performance simulation test method for steel-concrete composite structures according to the present invention.

[0050] Figure 4 This is a schematic diagram showing the comparison of frequency band energy before and after standardization in the first embodiment of the seismic performance simulation test method for steel-concrete composite structures according to the present invention.

[0051] Figure 5 This is a schematic diagram of the spatial distribution of local buckling index in a first embodiment of the seismic performance simulation test method for steel-concrete composite structures according to the present invention.

[0052] Figure 6 This is a schematic diagram of the spatial distribution of concrete crushing damage index in the first embodiment of the seismic performance simulation test method for steel-concrete composite structures of the present invention.

[0053] Figure 7 This is a schematic diagram of the time evolution of the coupled failure index in a first embodiment of the seismic performance simulation test method for steel-concrete composite structures according to the present invention.

[0054] Figure 8 This is a schematic diagram of the equipment used in the seismic performance simulation test method for steel-concrete composite structures according to the present invention. Detailed Implementation

[0055] 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.

[0056] Example 1: As Figure 1 The diagram shown is a flowchart of the first embodiment of the seismic performance simulation test method for steel-concrete composite structures of the present invention, which presents the first embodiment of the seismic performance simulation test method for steel-concrete composite structures of the present invention.

[0057] In the first embodiment, the seismic performance simulation test method for the steel-concrete composite structure includes:

[0058] Step S10: Obtain the parameter set of the steel-concrete composite structure, and perform coupled discrete modeling task based on the parameter set using a unified parametric finite element modeling mechanism to output the initial discrete model. and standardized earthquake input sequence ;

[0059] It should be noted that the parameter set of a steel-concrete composite structure refers to all the necessary geometric parameters, material property parameters, and initial defect parameters that constitute the steel-concrete composite structure. Specifically, geometric parameters include the outer diameter, wall thickness, and member length of the steel tube, which directly affect the geometric stability and seismic resistance of the structure; material parameters include the elastic modulus, yield strength, hardening modulus of steel and concrete, peak compressive strength, and peak strain of concrete, which determine the stress-strain response of the structural materials under seismic loading; initial defect parameters include the defect amplitude ratio at the interface between the steel tube and concrete, and the surface inhomogeneity of the structure, which have a significant impact on the initial state of the structure and its seismic performance.

[0060] Understandably, by employing a unified parametric finite element modeling mechanism, all structural parameters can be effectively transformed into a computable finite element model, enabling the model to accurately reflect the coupling effect and complex nonlinear behavior of the steel tube and concrete. After establishing the initial discrete model, the seismic input sequence is standardized to ensure that the seismic intensity and frequency in the simulation process are consistent with the actual response spectrum, thus guaranteeing the accuracy and practicality of the model. This modeling mechanism is not only applicable to different types of steel-concrete composite structures but also ensures computational accuracy under various working conditions.

[0061] For example, such as Figure 2 As shown, the steel pipe region and the core concrete region are represented by discrete nodes, with the outer edge of the steel pipe superimposed with an initial defect morphology consistent with the buckling mode. This schematic diagram demonstrates that the unified parametric finite element modeling mechanism can simultaneously consider geometric dimensions, material parameters, and initial defect factors during the modeling stage, enabling the discrete model to possess the initial imperfection characteristics of a real engineering structure, providing a physically consistent computational basis for subsequent buckling identification and nonlinear response analysis. Figure 3 As shown, the standardized seismic input sequence, while preserving the original waveform characteristics, is proportionally adjusted to ensure that the peak ground acceleration meets the target response spectrum requirements. This processing ensures the comparability of input intensities under different seismic conditions, while avoiding interference with numerical stability caused by excessively large or small original input amplitudes, thus improving the stability and consistency of subsequent nonlinear time history analysis. Figure 4 As shown, the standardization process mainly adjusts the overall amplitude, achieving input intensity consistency while preserving the main frequency band structural characteristics. Frequency domain comparison demonstrates that this method does not change the main control frequency band of the structural response, but only scales the amplitude proportionally, thereby improving the comparison accuracy and engineering repeatability between different simulation conditions while ensuring physical rationality.

[0062] Step S20: Based on the initial discrete model A characteristic buckling mode tracking mechanism is used to perform the critical buckling identification task and output a defect correction model. ;

[0063] It should be noted that the "characteristic buckling mode tracking mechanism" in this step refers to constructing a geometric stiffness matrix by introducing an axial preloading condition based on the established initial discrete model. This geometric stiffness matrix, along with the initial elastic stiffness matrix, participates in eigenvalue analysis to obtain the critical buckling eigenvalue set and corresponding buckling mode vectors of the structure. The eigenvalue set reflects the critical amplification coefficient of different potential instability modes, and the buckling mode vectors describe the deformation distribution of the structure under critical conditions. By sorting the eigenvalues ​​and selecting the mode corresponding to the smallest positive eigenvalue as the dominant buckling mode, the most likely local buckling forms can be identified. Subsequently, the buckling modes are scaled according to a preset defect proportion coefficient and superimposed onto the original discrete model using nodal coordinate perturbation to construct a defect correction model. This defect correction model is used to simulate the unavoidable initial geometric defect state in actual engineering.

[0064] Understandably, by employing the characteristic buckling mode tracking mechanism, potential weak and unstable regions of the structure under axial compression can be identified in advance before formal strong earthquake nonlinear time history analysis, allowing the model to transition from an "ideal geometric state" to an "engineering-realistic initial state." This process makes subsequent analysis closer to the actual structural stress behavior, avoiding deviations in buckling location and mode from reality due to idealized modeling. Simultaneously, using dominant buckling modes for defect injection helps improve the sensitivity of numerical analysis to local buckling development, making subsequent calculations of coupled failure indices more physically meaningful.

[0065] It should be understood that, compared to the traditional approach of directly applying strong seismic loads to an ideal geometric model in nonlinear analysis, this step, through a defect construction method guided by buckling modes, imbues the initial model with prior information related to structural stability. Traditional methods often only reveal buckling characteristics after the structure has entered a significant plastic stage, leading to numerical results that are sensitive to the mesh and exhibit significant randomness in buckling morphology. This invention, by introducing the dominant buckling modes in advance, significantly reduces the dependence of the calculation results on mesh generation and initial perturbations, improving the consistency and repeatability of buckling identification. Simultaneously, this mechanism effectively reduces the risk of sudden stiffness degradation in subsequent nonlinear iterations, enhancing overall numerical stability.

[0066] Step S30: Based on the defect correction model A coupling mechanism between local buckling index and concrete crushing damage index is used to perform nonlinear material pretreatment, and the coupled failure index is output. ;

[0067] It should be noted that the "local buckling index" in this step refers to a quantitative parameter characterizing the degree of local stability degradation of the steel pipe, constructed based on the rate of change of curvature of the steel pipe unit, the equivalent plastic strain increment, and the degree of axial compressive stress concentration. The "concrete crushing damage index" refers to a quantitative parameter reflecting the degree of concrete crushing, constructed based on the proportional relationship between the principal compressive strain and peak strain in the concrete compression zone, combined with the damage evolution law. The so-called "coupling mechanism" refers to the synergistic fusion of the above two indices according to preset weights to form a unified coupled failure index, used to characterize the degree of synergistic evolution of local buckling of the steel pipe and core concrete crushing. The material nonlinear preprocessing task does not directly enter the complete strong earthquake iteration, but before the formal time history analysis, by applying a small loading or predictive response analysis to the defect correction model, it identifies the region where the material enters the nonlinear stage in advance and calculates the corresponding buckling and damage development trends, thereby providing a priori failure information for subsequent numerical stability control.

[0068] Understandably, during the actual stress process of concrete-filled steel tube (CFST) members, local buckling of the steel tube often reduces its restraint on the core concrete, making the concrete more prone to crushing. Conversely, concrete crushing weakens the supporting effect of the steel tube, accelerating the instability of the steel tube wall. Therefore, relying solely on the yielding or damage of a single material as a criterion cannot comprehensively describe the overall structural instability trend. The coupled failure index constructed in this step can identify the "buckling-crushing" co-evolution trend in advance, before the material has fully entered the macroscopic failure stage. For example, when the local curvature of the steel tube has increased significantly but the concrete damage has not yet reached its limit, the coupled index can still reflect the increased risk of co-evolution, thus providing a more sensitive early warning signal for the subsequent numerical stability control mechanism. In other words, this step elevates the local nonlinear behavior at the material level to a co-evolutionary instability evaluation parameter at the structural level, enabling the numerical stability control in subsequent step S40 to no longer rely solely on residuals or energy mutations, but to perform predictive adjustments based on the actual failure mechanism.

[0069] For example, such as Figure 5 As shown, the local buckling index exhibits a significant high-value band in the middle region along the member's length and shows a local concentration characteristic in the circumferential direction. This phenomenon indicates the existence of a weak zone in the defect correction model that is more sensitive to local buckling. This weak zone is not uniformly distributed along the circumference but rather forms a local unstable hotspot region due to the combined effects of the rate of curvature change, the equivalent plastic strain increment, and the concentration of axial compressive stress. Based on this spatial distribution result, key element clusters that "may occur first in local buckling of the steel tube" can be identified before entering the strong earthquake nonlinear time history iteration, providing prior information for subsequent construction of coupled failure indices and stabilization control. Figure 6 As shown, the concrete crushing damage index forms a relatively continuous high-value area near the middle of the member, and its circumferential expansion range is relatively large. Figure 5The effect is broader. This result reflects a more pronounced "planar diffusion" characteristic in the crushing damage evolution of the core concrete. That is, as the principal compressive strain gradually approaches the peak strain, the damage area often expands first along a certain length and then gradually increases in the circumferential direction. This distribution characteristic can provide a key basis for subsequent coupled failure determination: when the high-value area of ​​concrete damage spatially overlaps with the high-value area of ​​steel tube buckling, the structure is more likely to enter the critical stage of buckling-crushing coordinated instability. For example... Figure 7 As shown, the single index reflects the independent development trends of local buckling of the steel tube and crushing damage of the concrete, respectively, and the two exhibit asynchronous upward processes during the main excitation stage of a strong earthquake. However, the coupled index, due to the introduction of a synergistic fusion mechanism, shows a more sensitive increase in the stage of "simultaneous accelerated development of buckling and crushing," and reaches the synergistic instability warning threshold earlier. This result indicates that when the structure has not yet shown obvious macroscopic damage characteristics, the coupled index can provide early warning signals of synergistic instability, thus providing a more reliable and physically consistent control basis for the adaptive time step and stability damping adjustment in subsequent step S40, avoiding the lag adjustment problem caused by traditional methods that rely solely on residuals or energy mutations.

[0070] Step S40: Based on coupling failure index and standardized earthquake input sequence An energy ratio-driven adaptive value stabilization control mechanism is used to perform the stabilization parameter generation task and output a set of stabilization parameters. ;

[0071] It should be noted that the "energy ratio-driven adaptive numerical stabilization control mechanism" in this step refers to a stabilization control strategy that adaptively adjusts key numerical parameters such as time step, numerical damping coefficient, and tangent stiffness update frequency by calculating the ratio between structural kinetic energy and internal energy in real time before and during the strong earthquake nonlinear time history analysis, and combining this with the coupled failure index obtained in step S30. Kinetic energy refers to the overall kinetic energy of the structure at a given moment, generated by nodal velocities, while internal energy refers to the strain energy stored by the nonlinear deformation and plastic development of the material. By constructing the energy ratio index of "kinetic energy to internal energy," it is possible to determine whether the current structural response is in a severe vibration stage or has entered a stiffness degradation stage. The so-called "stabilization parameter set" includes, but is not limited to, parameters such as adaptive time step, equivalent numerical damping correction coefficient, tangent stiffness update threshold, and residual convergence control tolerance. These parameters are not fixed values ​​but are dynamically generated based on the coordinated changes of the coupled failure index and the energy ratio index, thereby ensuring that the numerical solution process maintains physical accuracy while avoiding computational divergence caused by sudden stiffness drops or damage propagation.

[0072] Understandably, under strong earthquakes, concrete-filled steel tubular structures often undergo an evolutionary process of "elastic stage – local plastic development – ​​coordinated development of local buckling and crushing – significant degradation of overall stiffness." When the coupled failure index is at a low level, the structural response is relatively stable, and a larger time step can be used to improve computational efficiency. However, when the coupled failure index rises rapidly and the ratio of kinetic energy to internal energy fluctuates significantly, it indicates that the structure may be entering a stage of pre-instability coordination. If a fixed time step or fixed damping parameters are still used, iterative oscillations or singular stiffness matrix problems are likely to occur. The adaptive stability control mechanism constructed in this step can automatically reduce the time step and appropriately increase numerical damping as the coupled failure index rises, thereby smoothing the numerical oscillations during the stiffness degradation process and making the nonlinear iterative process more stable. In addition, when the energy ratio recovers to a relatively stable range, the time step limit can be automatically relaxed to avoid unnecessary waste of computational resources. Therefore, this step essentially establishes a direct mapping relationship between the "structural physical failure trend" and "numerical solution stability control," giving the numerical stability strategy a physical basis rather than simply adjusting based on algorithmic experience. For example, in the strong-earthquake nonlinear analysis of a concrete-filled steel tube column, the structure initially exhibits a predominantly overall vibration response during the early stages of the main shock, with coupled failure indices remaining relatively stable and the ratio between kinetic and internal energy showing slight periodic fluctuations. At this point, it is determined that the structure has not yet entered a significant buckling-crushing co-instability stage, thus maintaining a relatively relaxed time step and numerical damping settings to improve computational efficiency. As the earthquake input continues to intensify, local buckling development and concrete crushing damage begin to overlap spatially, and the coupled failure indices show an accelerating growth trend. Simultaneously, the internal energy growth rate is significantly higher than the kinetic energy growth rate, and the energy ratio indices show a continuous deviation. Upon identifying this co-evolutionary characteristic, the time step is automatically reduced, and the numerical damping and stiffness update frequency are adjusted synchronously to smooth out the stiffness degradation process and avoid numerical oscillations during the nonlinear abrupt change stage. In the subsequent response stage, when the growth trend of the coupled failure indices stabilizes and the energy ratio returns to a relatively balanced range, the time step and damping parameters are gradually restored to normal levels, thus balancing computational stability and efficiency.

[0073] Step S50: Based on the set of stabilization parameters Coupling failure index and standardized earthquake input sequences Perform nonlinear time history iterative solution for strong earthquakes and output a set of seismic performance indices. With coupling failure region .

[0074] It should be noted that the "strong earthquake nonlinear time history iterative solution" in this step refers to the process of solving the structural dynamic equilibrium equations time-by-time, based on the defect correction model constructed in the previous steps, introducing a standardized earthquake input sequence as an external excitation, and combining it with the stabilization parameter set generated in step S40. The "stabilization parameter set" includes adaptive time step, numerical damping correction coefficient, tangent stiffness update control parameters, and convergence tolerance control parameters. These parameters are dynamically adjusted at each time step according to the coupled failure index and energy ratio index to ensure the continuity and stability of the nonlinear solution process. During the solution process, the coupled failure index is not merely a post-processing result but participates in the iterative update as a state variable. When the element enters the buckling-crushing co-evolution stage, its local stiffness degradation law, equivalent damping characteristics, and material tangent modulus are all corrected according to the coupled failure index, thereby achieving real-time coupling between material nonlinearity and structural dynamic response. The “seismic performance index set” includes indicators such as structural bearing capacity degradation trend, overall stiffness degradation trend, hysteretic energy dissipation capacity, residual deformation distribution, and ductility development level; the “coupled failure region” refers to the unit region where the coupled failure index continuously exceeds the preset threshold and forms spatial connectivity throughout the entire time history analysis process, which is used to characterize the actual spatial location of the coordinated development of local buckling of steel tube and crushing of core concrete.

[0075] Understandably, in the nonlinear analysis stage of strong earthquakes, the structural response no longer exhibits simple linear vibration, but rather undergoes a complex process involving stiffness degradation, plastic development, local instability propagation, and overall stress redistribution. Without introducing a linkage mechanism between stabilization parameters and coupled failure indices, the calculation process is prone to discontinuous responses due to sudden drops in local stiffness or stress concentration. This iterative solution method allows for the synchronous updating of the structural stiffness and damping matrices at each time step, ensuring consistency with the current degree of coupled failure. When the coupled failure index rises significantly in a certain region, the stiffness in that region automatically decreases, the structural force path redistributes, and the calculation process maintains continuous convergence. Therefore, this step achieves a closed-loop linkage between "physical failure evolution—numerical solution control—performance index output," ensuring that the final seismic performance index not only reflects the overall response trend but also accurately corresponds to the actual failure area.

[0076] It should be understood that, compared to traditional strong earthquake time history analysis methods that determine the failure location only after calculation based on stress or strain results, this invention introduces coupled failure indices into the entire iterative process, making failure determination a dynamic variable rather than a post-event evaluation indicator. Traditional methods often extract the failure region based on maximum strain or maximum displacement after calculation, which fails to reflect the evolution path of failure formation and cannot explain the relationship between numerical oscillations and physical instability. This invention, by tracking the spatial distribution and temporal evolution trend of coupled failure indices in real time during the solution process, can identify the entire process of failure development from local to regional expansion, thus revealing the instability mechanism more accurately. Furthermore, since the stabilization parameter set is adjusted according to the coupled failure indices at each step, the stiffness abrupt change problem caused by fixed parameters in traditional algorithms is avoided, ensuring that the solution results maintain physical rationality and numerical continuity even in the extreme stages of strong earthquakes.

[0077] For example, in the strong earthquake analysis of a concrete-filled steel tube member, the initial structural response exhibits elastic vibration, with coupled failure indices remaining at a low level, and both bearing capacity and stiffness showing a stable state. As the seismic input intensifies, the coupled failure indices in the central region gradually increase. During the iteration process, the tangential stiffness in this region is automatically reduced, and the damping adjustment coefficient is appropriately increased. In the subsequent time intervals, this region gradually forms a spatially connected high-coupled-indice zone, the bearing capacity curve begins to show a degradation trend, the hysteresis curve changes from a full shape to a contracted shape, and residual deformation gradually accumulates. Due to the dynamic adjustment of the stabilization parameter set, no stiffness matrix singularities or iterative oscillations occur during the entire solution process. The final output results show that the coupled failure region is concentrated on the biased side of the central part of the member, and the seismic performance index set can clearly reflect the bearing capacity degradation path and ductile development stage. By comparing the analysis results without the coupled stabilization mechanism, it can be found that traditional methods are more prone to numerical non-convergence or failure zone determination errors under the same working conditions, while the method of this invention can stably and continuously track the failure evolution process. Therefore, this step not only completes the task of solving the nonlinear response of strong earthquakes, but also realizes a complete closed loop from damage evolution identification to performance index output, making the seismic performance simulation test results have higher engineering interpretation ability and application reliability.

[0078] Example 2: Furthermore, the seismic performance simulation testing system for steel-concrete composite structures provided by this invention employs the seismic performance simulation testing method for steel-concrete composite structures described in the above embodiments, thereby solving the technical problem of seismic performance simulation testing for steel-concrete composite structures. The beneficial effects of the seismic performance simulation testing system for steel-concrete composite structures provided by this invention are the same as those of the seismic performance simulation testing method for steel-concrete composite structures provided in the above embodiments, and other technical features of the seismic performance simulation testing system for steel-concrete composite structures are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0079] Example 3: This invention provides a seismic performance simulation testing device for steel-concrete composite structures. Please refer to... Figure 8A seismic performance simulation testing device for a steel-concrete composite structure includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enable the at least one processor to perform the seismic performance simulation testing method for a steel-concrete composite structure as described in Embodiment 1 above. The seismic performance simulation testing device for a steel-concrete composite structure in this embodiment of the invention may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), and vehicle terminals (e.g., vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. This seismic performance simulation testing device for a steel-concrete composite structure is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of the invention. A seismic performance simulation testing device for steel-concrete composite structures may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes according to a program stored in a read-only memory 1002 or a program loaded from a storage device 1003 into a random access memory 1004. The random access memory 1004 also stores various programs and data required for the operation of the seismic performance simulation testing device for steel-concrete composite structures. The processing unit 1001, the read-only memory 1002, and the random access memory 1004 are interconnected via a bus 1005. An I / O interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. The communication device 1009 allows a seismic performance simulation testing device for steel-concrete composite structures to communicate wirelessly or wiredly with other devices to exchange data. Although the figure shows a seismic performance simulation testing device for steel-concrete composite structures with various systems, it should be understood that implementation or possession of all the systems shown is not required. More or fewer systems may be implemented alternatively.

[0080] Example 4: This invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the seismic performance simulation test method for a steel-concrete composite structure as described above. The computer program product provided by this invention can solve the technical problem of seismic performance simulation testing of a steel-concrete composite structure. Compared with the prior art, the beneficial effects of the computer program product provided by this invention are the same as the beneficial effects of the seismic performance simulation test method for a steel-concrete composite structure provided in the above embodiments, and will not be repeated here.

[0081] In particular, according to the embodiments disclosed in this invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this invention include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from read-only memory 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this invention.

[0082] It should be understood that the various parts disclosed in this invention can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0083] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for simulating and testing the seismic performance of concrete-filled steel tubular structures, characterized in that, The methods include: Step S10: Obtain the parameter set of the steel-concrete composite structure, and perform coupled discrete modeling task based on the parameter set using a unified parametric finite element modeling mechanism to output the initial discrete model. and standardized earthquake input sequence ; Step S20: Based on the initial discrete model A characteristic buckling mode tracking mechanism is used to perform the critical buckling identification task and output a defect correction model. ; Step S30: Based on the defect correction model A coupling mechanism between local buckling index and concrete crushing damage index is used to perform nonlinear material pretreatment, and the coupled failure index is output. ; Step S40: Based on coupling failure index and standardized earthquake input sequence An energy ratio-driven adaptive value stabilization control mechanism is used to perform the stabilization parameter generation task and output a set of stabilization parameters. ; Step S50: Based on the set of stabilization parameters Coupling failure index and standardized earthquake input sequences Perform nonlinear time history iterative solution for strong earthquakes and output a set of seismic performance indices. With coupling failure region .

2. The seismic performance simulation test method for steel-concrete composite structures as described in claim 1, characterized in that, In step S10, the parameter set of the steel-concrete composite structure is obtained. Based on the parameter set, a unified parametric finite element modeling mechanism is used to perform a coupled discrete modeling task, and the initial discrete model is output. and standardized earthquake input sequence The steps specifically include: Step S101: Obtain the parameter set of the steel-concrete composite structure, which includes the set of geometric parameters. Material parameter set Material density parameters and earthquake input sequences Among them, the set of material parameters This includes the elastic modulus of steel, the yield strength of steel, the hardening modulus of steel, the elastic modulus of concrete, the peak compressive strength of concrete, and the peak strain of concrete. Step S102: Based on the geometric parameter set in the parameter set of the steel-concrete composite structure and material parameter set The initial stiffness matrix is ​​constructed by assembling the stiffness matrix using the finite element method. Based on the geometric parameter set in the parameter set of concrete-filled steel tube structures. and material density parameters The mass matrix is ​​generated using a consistent mass matrix construction method. ; Step S103: Based on the initial stiffness matrix and mass matrix The structural eigenvalue solving task is performed using a node-coupled approach, outputting the first-order angular frequency. and the first-order periodicity of the structure ; Step S104: Based on the first-order angular frequency and the first-order periodicity of the structure The initial discrete model is constructed and output by adjusting the reaction spectrum ratio. And using the initial discrete model For earthquake input sequences Perform spectral consistency processing and output a standardized seismic input sequence. .

3. The seismic performance simulation test method for steel-concrete composite structures as described in claim 2, characterized in that, In step S20, based on the initial discrete model A characteristic buckling mode tracking mechanism is used to perform the critical buckling identification task and output a defect correction model. The steps specifically include: Step S201: Construct a geometric stiffness reference matrix under preset axial preloading conditions, based on the geometric stiffness reference matrix and the initial stiffness matrix. Eigenvalue analysis is performed, an eigenvalue set is output, and the eigenvalue set is sorted from smallest to largest. The eigenvector corresponding to the smallest positive eigenvalue is selected as the buckling mode vector. Step S202: Normalize the buckling mode vector and output the normalized buckling mode vector; set the initial defect amplitude according to the preset steel pipe wall thickness ratio, and construct the actual buckling morphology defect function based on the initial defect amplitude and the normalized buckling mode vector, combined with the amplitude ratio mapping function. Step S203: Superimpose the actual buckling morphological defect function onto the initial discrete model using a nodal coordinate perturbation superposition method. Output defect correction model .

4. The seismic performance simulation test method for steel-concrete composite structures as described in claim 3, characterized in that, In step S202, the initial defect amplitude does not exceed 0.5 times the wall thickness of the steel pipe, and the modal amplitude normalization method is used for extreme value truncation to prevent abnormal stiffness distortion of local elements.

5. The seismic performance simulation test method for steel-concrete composite structures as described in claim 1, characterized in that, In step S30, based on the defect correction model A coupling mechanism between local buckling index and concrete crushing damage index is used to perform nonlinear material pretreatment, and the coupled failure index is output. The steps specifically include: Step S301: Obtain the yield strength and hardening modulus of the steel, and construct a plastic yield determination function based on the yield strength and hardening modulus of the steel. The plastic yield determination function is used to determine whether the steel has entered the plastic stage. Step S302: Obtain the earthquake input sequence Using a defect correction model For earthquake input sequences Initial nonlinear response prediction processing is performed to output the unit-level equivalent strain response sequence; the plastic yield criterion function is used to perform plastic state screening processing on the unit-level equivalent strain response sequence to output the set of units that have entered the plastic stage. Step S303: Extract the principal compressive strain response of the corresponding concrete compression zone based on the set of units that have entered the plastic stage, obtain the peak strain of the concrete, and perform proportional mapping processing on the principal compressive strain response based on the peak strain of the concrete to output the set of damage evolution degree of the concrete compression zone; extract the maximum damage value in the set of damage evolution degree of the concrete compression zone as the concrete crushing index. Step S304: Obtain the rate of change of curvature of the steel pipe unit, and perform weighted coupling based on the rate of change of curvature of the steel pipe unit and the concrete crushing index according to preset weights, and output the coupled failure index. Coupling failure index Characterizes the degree of synergistic failure between local buckling of the steel pipe and crushing of the concrete.

6. The seismic performance simulation test method for steel-concrete composite structures as described in claim 1, characterized in that, In step S40, based on the coupling failure index and standardized earthquake input sequence An energy ratio-driven adaptive value stabilization control mechanism is used to perform the stabilization parameter generation task and output a set of stabilization parameters. The steps specifically include: Step S401: Preset the initial time step. In each initial time step, based on the standardized seismic input sequence... The incremental dynamic balance prediction method is used to obtain the structural kinetic energy and internal energy, and an energy ratio index is constructed based on the structural kinetic energy and internal energy. Step S402: Combine the energy ratio index with the coupling failure index A linear weighted fusion method is used for collaborative fusion to form a numerical instability risk assessment value; Step S403: Adaptively adjust the initial time step based on the numerical instability risk assessment value; when the numerical instability risk assessment value exceeds the preset first risk threshold, decrease the initial time step; when the numerical instability risk assessment value is less than or equal to the first risk threshold, increase the initial time step; finally, output the set of stable parameters that change over time. Stabilization parameter set This includes time step control and stability damping adjustment.

7. The seismic performance simulation test method for a steel-concrete composite structure as described in claim 6, characterized in that, In step S50, based on the set of stabilization parameters... Coupling failure index and standardized earthquake input sequences Perform nonlinear time history iterative solution for strong earthquakes and output a set of seismic performance indices. With coupling failure region The steps specifically include: Step S501: Based on the set of stabilization parameters Coupling failure index and standardized earthquake input sequences A stabilized dynamic equation is established using an improved implicit dynamics principle; in this step, a time step control term and a stability damping adjustment term are introduced. Step S502: Based on the stabilized dynamic equation, an implicit integration algorithm is used to perform time history iteration, outputting the structural displacement response sequence and the element strain response sequence. The coupled failure index is then determined based on the structural displacement response sequence and the element strain response sequence. Perform iterative corrections and output optimized coupling failure indicators. ; Step S503: When optimizing coupling failure indicators When the second preset risk threshold is exceeded, the steel-concrete composite structure is determined to have entered the buckling and crushing coupled failure stage. A set of seismic performance indicators is then extracted during this stage. With coupling failure region Among them, the set of seismic performance indicators This includes the rate of degradation of bearing capacity, the rate of degradation of stiffness, and residual deformation.

8. A seismic performance simulation and testing system for steel-concrete composite structures, applied to the seismic performance simulation and testing method for steel-concrete composite structures according to any one of claims 1 to 7, characterized in that, The seismic performance simulation and testing system for the steel-concrete composite structure includes: The parameter modeling module is used to obtain the parameter set of the steel-concrete composite structure. Based on the parameter set, it performs coupled discrete modeling tasks using a unified parametric finite element modeling mechanism and outputs an initial discrete model. and standardized earthquake input sequence ; The buckling recognition module is used to identify buckling based on the initial discrete model. A characteristic buckling mode tracking mechanism is used to perform the critical buckling identification task and output a defect correction model. ; The coupling index construction module is used for defect correction models. A coupling mechanism between local buckling index and concrete crushing damage index is used to perform nonlinear material pretreatment, and the coupled failure index is output. ; Numerical stability control module, used for coupling failure index and standardized earthquake input sequence An energy ratio-driven adaptive value stabilization control mechanism is used to perform the stabilization parameter generation task and output a set of stabilization parameters. ; The seismic performance output module is used to output seismic performance based on the set of stabilization parameters. Coupling failure index and standardized earthquake input sequences Perform nonlinear time history iterative solution for strong earthquakes and output a set of seismic performance indices. With coupling failure region .

9. A seismic performance simulation and testing device for steel-concrete composite structures, characterized in that, The seismic performance simulation testing equipment for steel-concrete composite structures includes: a memory, a processor, and a seismic performance simulation testing program for steel-concrete composite structures stored in the memory and executable on the processor. When the seismic performance simulation testing program for steel-concrete composite structures is executed by the processor, it implements a seismic performance simulation testing method for steel-concrete composite structures according to any one of claims 1 to 7.

10. A computer program product, characterized in that, The computer program product includes a seismic performance simulation test program for steel-concrete composite structures. When the seismic performance simulation test program for steel-concrete composite structures is executed by a processor, it implements a seismic performance simulation test method for steel-concrete composite structures according to any one of claims 1 to 7.

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