Anchorage zone failure mechanism analysis method and system based on finite element verification

Abstract

The application provides an anchorage zone damage mechanism analysis method and system based on finite element verification, relates to the technical field of simulation and simulation, and comprises the following steps: local and global modeling of the anchorage zone of a multi-scale bridge expansion device is performed by using a finite element model, interface contact behavior is simulated, and corresponding mechanical indexes and damage variables are obtained; each mechanical index is subjected to correlation regression processing with interface bonding damage parameters and concrete matrix damage parameters, relevant factors of the two types of damage parameters are determined, the interface bonding damage parameters and the concrete matrix damage parameters are coupled based on the relevant factors, comprehensive damage parameters are obtained, and a first mapping relationship between the comprehensive damage parameters and the mechanical indexes is established; the comprehensive damage parameters are divided into a plurality of mapping intervals with different numerical ranges, in each mapping interval, a corresponding damage master control factor is obtained, the first mapping relationship is corrected, a target mapping relationship is obtained, and a damage evolution process of the anchorage zone is determined.

Description

Technical Field

[0001] This invention relates to the field of simulation technology, and in particular to a method and system for analyzing the failure mechanism of the anchorage zone based on finite element verification. Background Technology

[0002] Bridge expansion joints are critical load-bearing components that adapt to temperature deformation, deflection, and shrinkage / creep of the bridge beam. The integrity of the concrete in the anchorage zone directly determines the service life of the expansion joint. Interface debonding, concrete cracking, localized spalling, and large-area spalling, leading to secondary defects such as steel profile misalignment, damaged sealing rubber, vehicle slumping, and rainwater erosion of the main beam reinforcement, directly affect the condition of the anchorage zone. Relying on manual visual inspection and localized ultrasonic flaw detection can only provide qualitative descriptions, lacking unified quantitative mechanical standards. It is impossible to distinguish whether the defects are caused by excessive weight, horizontal impact, material modulus mismatch, or insufficient interface friction, making it difficult to make appropriate maintenance decisions. At the same time, it is difficult to accurately measure the overall damage to the expansion joint, resulting in a lack of accurate management throughout the entire life cycle of the expansion joint. Summary of the Invention

[0003] In view of this, the present invention proposes a method and system for analyzing the failure mechanism of the anchorage zone based on finite element verification.

[0004] The technical solution of this invention is implemented as follows: The first aspect of this invention provides a method for analyzing the failure mechanism of the anchorage zone based on finite element verification, comprising: The finite element model is used to model the anchorage zone of a multi-scale bridge expansion joint locally and globally, simulate the interface contact behavior, and obtain the corresponding mechanical indices and damage variables. The mechanical indices include field stress and interface deformation parameters in different directions, and the damage variables include interface bond damage parameters and concrete matrix damage parameters. Each of the mechanical indices is correlated with the interfacial bond damage parameter and the concrete matrix damage parameter through correlation regression to determine the correlation factors for each of the two types of damage parameters. Based on the correlation factors, the interfacial bond damage parameter and the concrete matrix damage parameter are coupled to obtain a comprehensive damage parameter, and a first mapping relationship between the comprehensive damage parameter and the mechanical indices is established. The comprehensive damage parameters are divided into multiple mapping intervals with different numerical ranges. In each mapping interval, the corresponding main damage control factors are obtained to correct the first mapping relationship and obtain the target mapping relationship. The damage evolution process of the anchorage zone is determined based on the target mapping relationship. The main damage control factors include at least one of stress concentration characteristics, interface shear stress, interface slip, debonding area, and vertical displacement.

[0005] Based on the above technical solutions, preferably, the step of using a finite element model to perform local and global modeling of the anchorage zone of a multi-scale bridge expansion joint, simulating interface contact behavior, and obtaining corresponding mechanical indicators and damage variables includes: Based on ANSYS finite element software, local and global models of modular, seamless, and comb-plate type expansion joints were established respectively. Solid45 solid elements were used to simulate beams, bridge deck pavement, elastic bodies, anchorage zone concrete and cross joint plates. Conta173 face-to-face contact elements and Targe170 target elements were used to simulate interface contact behavior. Multi-scale coupling of the anchorage zone was achieved through displacement boundary conditions. Different levels of load were applied to the anchorage zone to obtain the corresponding mechanical indices and damage variables.

[0006] Based on the above technical solutions, preferably, the relevant factors include a first relevant factor and a second relevant factor; the step of performing correlation regression processing on each of the mechanical indicators with the interfacial bond damage parameter and the concrete matrix damage parameter to determine the relevant factors for each of the two types of damage parameters includes: Based on the current actual bond strength and the initial design bond strength of the interface, the interface bond damage parameters are determined. Combining the interface bond damage parameters with the degree of influence of the various mechanical indicators, the first correlation factor is obtained. Based on the measured strain of the concrete in the anchorage zone under the current load, the benchmark strain under the same load in the initial service state, and the ultimate failure strain of the concrete, the damage parameters of the concrete matrix are determined. Combining the damage parameters of the concrete matrix with the degree of influence of the various mechanical indices, a second correlation factor is obtained.

[0007] Based on the above technical solutions, preferably, the step of coupling the interfacial bond damage parameters and the concrete matrix damage parameters based on the relevant factors to obtain comprehensive damage parameters includes: The first and second related factors are normalized to obtain the corresponding weighted contribution coefficients, and the coupling amplification coefficient is obtained by fitting the regression residuals. The damage cross-coupling term is introduced using the coupling amplification factor, and the comprehensive damage parameter is determined by combining the interfacial bond damage parameter, the concrete matrix damage parameter, and the corresponding related factors. The damage cross-coupling term characterizes the synergistic deterioration coupling effect between the interfacial bond damage parameter and the concrete matrix damage parameter.

[0008] Based on the above technical solutions, preferably, establishing the first mapping relationship between the comprehensive damage parameters and the mechanical indices includes: Using the set of mechanical indices as independent variables and the comprehensive damage parameters as dependent variables, a regression model is established, and the model is fitted using the least squares method to determine the first mapping relationship.

[0009] Based on the above technical solution, preferably, the step of dividing the comprehensive damage parameters into multiple mapping intervals with different numerical ranges, and obtaining the corresponding main damage control factors in each mapping interval to correct the first mapping relationship to obtain the target mapping relationship, includes: Based on the damage evolution process, the comprehensive damage parameters are divided into the microcrack initiation stage, the debonding and propagation stage, and the concrete spalling stage. During the microcrack initiation period, the corresponding first damage controlling factor is obtained; the first damage controlling factor includes stress concentration characteristics and interface shear stress. During the debonding propagation period, the corresponding second damage controlling factors are obtained; the second damage controlling factors include interfacial shear stress, interfacial slip, and debonding area. During the concrete spalling period, the corresponding third major damage control factor is obtained; the third major damage control factor includes vertical displacement and debonding area.

[0010] Based on the above technical solutions, preferably, the step of dividing the comprehensive damage parameters into multiple mapping intervals with different numerical ranges, and obtaining the corresponding main damage control factors in each mapping interval to correct the first mapping relationship and obtain the target mapping relationship, further includes: Based on the inherent stress level differences of different types of expansion joints, a type correction coefficient is determined to correct the first mapping relationship; When fitting the first mapping function for different mapping intervals, add a continuity boundary constraint.

[0011] Furthermore, a second aspect of the present invention provides a system for analyzing the failure mechanism of anchorage zones based on finite element verification, comprising: a parameter acquisition module, a parameter coupling module, and a process determination module; wherein, The parameter acquisition module is configured to use a finite element model to perform local and global modeling of the anchorage zone of a multi-scale bridge expansion joint, simulate interface contact behavior, and acquire corresponding mechanical indices and damage variables. The mechanical indices include field stress and interface deformation parameters in different directions, and the damage variables include interface bond damage parameters and concrete matrix damage parameters. The parameter coupling module is configured to perform correlation regression processing on each of the mechanical indices with the interfacial bond damage parameters and the concrete matrix damage parameters to determine the correlation factors of the two types of damage parameters, and couple the interfacial bond damage parameters and the concrete matrix damage parameters based on the correlation factors to obtain a comprehensive damage parameter, and establish a first mapping relationship between the comprehensive damage parameter and the mechanical indices. The process determination module is configured to divide the comprehensive damage parameters into multiple mapping intervals with different numerical ranges, obtain the corresponding main damage control factors in each mapping interval, modify the first mapping relationship to obtain the target mapping relationship, and determine the damage evolution process of the anchorage zone based on the target mapping relationship; the main damage control factors include at least one of stress concentration characteristics, expansion joint type difference characteristics, additional stress characteristics, and horizontal force influence characteristics.

[0012] More preferably, a third aspect of the present invention provides an electronic device, including a processor and a memory; the memory stores a computer program, wherein the computer program, when executed by the processor, implements the anchorage zone failure mechanism analysis method based on finite element verification described in the first aspect.

[0013] More preferably, the fourth aspect of the present invention provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the anchorage zone failure mechanism analysis method based on finite element verification as described in the first aspect.

[0014] The anchorage zone failure mechanism analysis method and system based on finite element verification of the present invention have the following advantages over the prior art: 1. By using the finite element model to model the anchorage zone of a multi-scale bridge expansion joint locally and globally, the interface contact behavior is simulated, and the corresponding mechanical indicators and damage variables are obtained. Each mechanical indicator is correlated with the interface bond damage parameter and the concrete matrix damage parameter through correlation regression to determine the relevant factors for each type of damage parameter. Based on the relevant factors, the interface bond damage parameter and the concrete matrix damage parameter are coupled to obtain the comprehensive damage parameter, and a first mapping relationship between the comprehensive damage parameter and the mechanical indicator is established. The comprehensive damage parameter is divided into multiple mapping intervals with different numerical ranges. In each mapping interval, the corresponding main damage control factors are obtained to correct the first mapping relationship and obtain the target mapping relationship. This determines the damage evolution process of the anchorage zone, realizing quantitative analysis of the anchorage zone state and accurate control of the entire life cycle of the expansion joint.

[0015] 2. Correlation regression was performed on all mechanical indices and damage variables respectively. Objective correlation factors were obtained through calculation, and the driving weights of various mechanical indices on the two types of damage were quantified. Then, the two types of damage were weighted and coupled based on the correlation factors and a synergistic degradation interaction term was introduced to obtain dimensionless comprehensive damage parameters. The entire process relied on finite element calculation data for automatic fitting, eliminating the subjective error of manual detection, unifying the industry's quantitative evaluation standard for anchorage zone damage, and conforming to the physical laws of real structural degradation.

[0016] 3. The comprehensive damage parameters are divided into multiple numerical mapping intervals. For each interval, specific damage-controlling factors are identified, and the first mapping relationship is modified accordingly to obtain the target mapping relationship. After segmented modification, the mapping curve better matches the characteristics of progressive damage acceleration evolution, eliminates the stage calculation errors caused by the unified mapping, and significantly improves the accuracy of damage evolution prediction. Attached Figure Description

[0017] 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.

[0018] Figure 1 A flowchart illustrating a method for analyzing the failure mechanism of the anchorage zone based on finite element verification, provided in an embodiment of the present invention; Figure 2 A schematic diagram of a failure mechanism analysis system for anchorage zones based on finite element verification provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] In some embodiments, such as Figure 1 As shown, Figure 1 This is a flowchart illustrating a method for analyzing the failure mechanism of an anchorage zone based on finite element verification, provided by an embodiment of the present invention. The method for analyzing the failure mechanism of an anchorage zone based on finite element verification provided by the present invention includes: S110 uses a finite element model to model the anchorage zone of a multi-scale bridge expansion joint locally and globally, simulates the interface contact behavior, and obtains the corresponding mechanical indices and damage variables. The mechanical indices include field stress and interface deformation parameters in different directions, and the damage variables include interface bond damage parameters and concrete matrix damage parameters.

[0021] S120 performs correlation regression processing on each mechanical index with the interfacial bond damage parameter and the concrete matrix damage parameter to determine the correlation factors of the two types of damage parameters. Based on the correlation factors, the interfacial bond damage parameter and the concrete matrix damage parameter are coupled to obtain the comprehensive damage parameter, and the first mapping relationship between the comprehensive damage parameter and the mechanical index is established.

[0022] S130, the comprehensive damage parameters are divided into multiple mapping intervals with different numerical ranges. In each mapping interval, the corresponding main damage control factors are obtained to correct the first mapping relationship and obtain the target mapping relationship. The damage evolution process of the anchorage zone is determined based on the target mapping relationship. The main damage control factors include at least one of stress concentration characteristics, interface shear stress, interface slip, debonding area and vertical displacement.

[0023] In this embodiment, the anchorage zone of the expansion joint is a localized high-stress concentration area. The overall deformation of the entire bridge will bring additional stress to the anchorage zone, and a separate local model will underestimate the actual force. By outputting the beam end displacement field from the global full-bridge model as the forced displacement boundary of the local refined anchorage sub-model, a refined analysis from macroscopic overall force transmission to microscopic local refinement can be achieved. The driving mechanical factors of interface bond damage parameters and concrete matrix damage parameters are clearly distinguishable. Among them, interface bond damage parameters are mainly controlled by interface shear stress, slip, and debonding area, while concrete matrix damage parameters are mainly dominated by X-direction normal stress, YZ shear stress, stress concentration, and vertical displacement. Through multivariate correlation regression, based on a massive finite element sample, the correlation factors of each mechanical index on the two types of damage can be automatically solved. The value of the correlation factor represents the strength of the contribution of the mechanical index to the damage evolution.

[0024] Considering the bidirectional positive feedback degradation effect between interfacial debonding and concrete cracking—for example, interfacial debonding weakens the constraint, amplifies stress concentration in the concrete, and accelerates matrix cracking, while the decrease in concrete stiffness and crack propagation further increase the interfacial shear load, exacerbating debonding—normalized relevant factors are used as weights to weight and integrate interfacial bond damage parameters and concrete matrix damage parameters to obtain a unified dimensionless comprehensive damage parameter. This allows a single parameter to fully characterize the overall degradation degree of the anchorage zone.

[0025] Furthermore, the controlling factors of damage differ significantly at different stages. A unified basic mapping relationship cannot adapt to the nonlinear evolution patterns of each stage, leading to calculation errors. Therefore, multiple independent mapping intervals are defined based on the comprehensive damage value. Each interval is matched with the controlling mechanical factors of the corresponding stage, such as stress concentration, interface shear stress, interface slip, debonding area, and vertical displacement, as correction terms. Within each damage interval, a stage-specific controlling factor correction basic mapping function is introduced to perform piecewise calibration on the slope, weighting coefficient, and nonlinear terms of the mapping curve, resulting in a target mapping relationship that adapts to the stress degradation pattern of that stage. Simultaneously, continuous constraints are added to the interval boundaries to ensure that the piecewise curves are smooth and without abrupt changes, conforming to the physical nature of continuous damage accumulation. The target mapping relationship can output continuous, high-precision comprehensive damage values. Combined with the mechanical critical thresholds corresponding to each interval, the current damage evolution stage of the anchorage zone can be accurately determined. Furthermore, the growth trend of damage under continuous load with service life and load cycle count can be deduced, enabling early warning of hidden internal damage and quantitative assessment of the entire life cycle degradation process.

[0026] In some embodiments, a finite element model is used to locally and globally model the anchorage zone of a multi-scale bridge expansion joint, simulate interface contact behavior, and obtain corresponding mechanical indices and damage variables, including: Based on ANSYS finite element software, local and global models of modular, seamless, and comb-plate type expansion joints were established respectively. Solid45 solid elements were used to simulate beams, bridge deck pavement, elastic bodies, anchorage zone concrete and cross joint plates. Conta173 face-to-face contact elements and Targe170 target elements were used to simulate interface contact behavior. Multi-scale coupling of the anchorage zone was achieved through displacement boundary conditions. Different levels of load were applied to the anchorage zone to obtain the corresponding mechanical indices and damage variables.

[0027] In this embodiment, CONTA173 contact surface elements and TARGE170 target elements are paired to simulate the interface between the steel / elastic body and the anchored concrete. Relying on the penalty function-Lagrange hybrid algorithm, it can completely reproduce three types of stress states: intact bonding, local shear slip, and large-area debonding. It can directly output interface deformation and stress indices such as interface slip, debonding area, and interface shear / tensile stress. At the same time, it can invert interface bonding damage parameters and calculate concrete matrix damage parameters from solid element strain. Simultaneously, it can collect a complete set of quantitative data such as field stress, deformation, and double-layer damage, which makes up for the deficiency of manual inspection, which can only observe surface defects and cannot obtain internal micromechanical and damage data. In addition, highway-class I vehicle load, horizontal impact load, and multi-level overload load are used to reproduce the multi-causal coupled stress of overload, braking lateral impact, modulus mismatch, and insufficient interface friction, providing a sufficient sample dataset for subsequent correlation regression.

[0028] In some embodiments, the correlation factors include a first correlation factor and a second correlation factor; correlation regression analysis is performed on each mechanical index with the interfacial bond damage parameter and the concrete matrix damage parameter to determine the respective correlation factors for the two types of damage parameters, including: Based on the current actual bond strength and the initial design bond strength of the interface, the interface bond damage parameters are determined. Combining the interface bond damage parameters with the degree of influence of various mechanical indicators, the first correlation factor is obtained. Based on the measured strain of the concrete in the anchorage zone under the current load, the benchmark strain under the same load in the initial service state, and the ultimate failure strain of the concrete, the damage parameters of the concrete matrix are determined. Combining the damage parameters of the concrete matrix with the degree of influence of various mechanical indicators, the second correlation factor is obtained.

[0029] In this embodiment, the interfacial adhesion damage parameter It can be represented as: ; In the formula, The actual bond strength (MPa) at the current interface is obtained by inverting the interfacial shear stress calculated from the Conta-173 contact element; The initial bond strength (MPa) of the interface is designed. When Db=0, the interface is intact; when Db=1, the interface is completely debonded.

[0030] Damage parameters of concrete matrix It can be represented as: ; In the formula, The measured strain of the concrete in the anchorage zone under the current load is consistent with the nodal strain calculated by the Solid-45 element. The reference strain under the same load during initial service conditions; This represents the ultimate failure strain of concrete.

[0031] Interfacial bond damage parameters are mainly controlled by interfacial shear stress, slip, and debonding area, while concrete matrix damage parameters are mainly dominated by X-direction normal stress, YZ-direction shear stress, stress concentration, and vertical displacement. Through multivariate correlation regression, the correlation factors of each mechanical index for both types of damage can be automatically solved based on a massive amount of finite element samples. The values ​​of these correlation factors represent the strength of the contribution of each mechanical index to damage evolution.

[0032] In some embodiments, interfacial bond damage parameters and concrete matrix damage parameters are coupled based on relevant factors to obtain comprehensive damage parameters, including: The first and second correlation factors are normalized to obtain the corresponding weighted contribution coefficients, and the coupling amplification coefficient is obtained by fitting the regression residuals. A damage cross-coupling term is introduced using a coupling amplification factor. Combined with interfacial bond damage parameters, concrete matrix damage parameters, and corresponding related factors, the comprehensive damage parameter is determined. The damage cross-coupling term characterizes the synergistic deterioration coupling effect between interfacial bond damage parameters and concrete matrix damage parameters.

[0033] In this embodiment, comprehensive damage parameters It can be represented as: ; in, , These are the weighted contribution coefficients corresponding to the first and second relevant factors, respectively. It is the coupling amplification factor, which can be obtained by fitting the regression residuals and is always greater than 0.

[0034] In some embodiments, establishing a first mapping relationship between comprehensive damage parameters and mechanical indices includes: Using the set of mechanical indices as independent variables and the comprehensive damage parameters as dependent variables, a regression model is established, and the first mapping relationship is determined by fitting the model using the least squares method.

[0035] In this embodiment, the set of mechanical indices includes stress concentration characteristics, interfacial shear stress, interfacial slip, debonding area, and vertical displacement. A set of coefficients is found using the least squares method to minimize the sum of squared residuals between the predicted damage and the actual comprehensive damage from the entire set of mechanical indices. This allows for the direct output of the comprehensive damage from the input of a set of mechanical indices.

[0036] In some embodiments, the comprehensive damage parameters are divided into multiple mapping intervals with different numerical ranges. In each mapping interval, the corresponding main damage controlling factors are obtained to correct the first mapping relationship, resulting in a target mapping relationship, including: Based on the damage evolution process, the comprehensive damage parameters are divided into the microcrack initiation stage, the debonding and propagation stage, and the concrete spalling stage; During the microcrack initiation stage, the corresponding primary damage controlling factors are obtained; the primary damage controlling factors include stress concentration characteristics and interface shear stress. During the debonding propagation phase, the corresponding secondary damage controlling factors are obtained; the secondary damage controlling factors include interfacial shear stress, interfacial slip, and debonding area. During the concrete spalling period, the corresponding third major damage controlling factors were obtained; the third major damage controlling factors include vertical displacement and debonding area.

[0037] In this embodiment, the comprehensive damage parameter in the microcrack initiation period satisfies 0<D≤0.15. In the initial service period, the overall interface is well-bonded, with no obvious slip or large-area debonding. Local high stress concentration occurs in the anchorage zone under vehicle wheel load, and only local micro-elements on the interface bear shear and tensile stress. At this time, internal microcracks in concrete and interface micro damage are completely driven by stress concentration and interface shear stress. Changes in slip, overall debonding area and vertical displacement are extremely small, and contribute weakly to damage growth, so the above two factors are defined as the first damage main controlling factors. The comprehensive damage parameter in the debonding propagation period satisfies 0.15<D≤0.7. After local microcracks are connected, continuous shear slip begins to occur at the interface, the debonding area gradually expands, the load continuously transfers to the undebonded interface, and the interface shear stress continues to increase. The slip amount and debonding area form a positive feedback cycle of "slip expands debonding, and debonding increases shear stress". Vertical displacement is still in a small controllable range and is no longer a core control item. Interface shear stress, interface slip and debonding area jointly dominate the accelerated development of damage, and are used as the second damage main controlling factors. The comprehensive damage parameter in the concrete spalling period satisfies D>0.7. The interface debonding area exceeds 70%, the concrete in the anchorage zone loses interface restraint and forms a cantilever force-bearing plate, and the overall stiffness decreases significantly; enormous bending shear deformation occurs at the root of the cantilever under vertical load, vertical displacement increases sharply, and the debonding area approaches the critical failure range. At this time, stress concentration and local slip are no longer the control indicators, and vertical displacement and cumulative debonding area become the third damage main controlling factors that determine the shear spalling of concrete.

[0038] Three independent evolution intervals are divided according to the threshold of the comprehensive damage parameter D, and the mechanical indicators that play a leading role in the corresponding stage are screened as the exclusive main controlling factors in each interval, and the low-sensitivity mechanical indicators in this stage are weakened or eliminated. Taking the main controlling factors of each stage as correction terms, the first-order term, cross term and weight coefficient of the first mapping are recalibrated in sections, and a segmented target mapping relationship is constructed. After segmented correction, the mapping function fits the real damage growth rate of each stage, eliminates the systematic deviation caused by the unified global model, thereby improving the damage prediction accuracy.

[0039] In some embodiments, dividing the comprehensive damage parameter into a plurality of mapping intervals with different numerical ranges, and acquiring corresponding damage main controlling factors to correct the first mapping relationship to obtain the target mapping relationship further includes: Determining type correction coefficients based on the difference in inherent stress levels of different types of expansion devices, and correcting the first mapping relationship; When fitting the first mapping function of different mapping intervals, adding continuous boundary constraints.

[0040] In this embodiment, considering that the structural forms, stiffness systems, and force transmission paths of modular (MA), comb-plate (SC), and seamless expansion joints are completely different, there are inherent differences in the damage development rate of the anchorage zone under the same load and mechanical properties. For example, modular expansion joints have high steel stiffness and concentrated loads, resulting in the highest stress peak in the anchorage zone and the fastest damage development under the same interface shear stress and slippage. Comb-plate expansion joints have moderate stress and a moderate damage development rate. Seamless expansion joints rely on elastic bodies to distribute the load, resulting in the lowest stress level and the slowest damage growth under the same mechanical properties. Therefore, calibration is performed by comparing multiple sets of finite element test cases with the same parameters and different device types. Based on the simulation data, a type correction coefficient is determined to correct the first mapping relationship.

[0041] In addition, considering that the damage values ​​calculated by the left and right segments of the mapping may be unequal at the interval boundary point, resulting in numerical jumps, and that the damage growth rates of the two functions at the boundary point are inconsistent, which may cause the damage evolution curve to have an angle, two types of equality constraints are applied simultaneously when fitting each interval mapping function to force the piecewise curves to connect smoothly, eliminate abrupt changes in the calculation of the piecewise mapping boundary, avoid misjudgment of the damage stage near the boundary point, improve the accuracy of the full damage interval mapping, and ensure that the curve is smooth and continuous throughout the entire process from the initiation of microcracks to concrete spalling.

[0042] In some embodiments, please refer to Figure 2 , Figure 2 This is a schematic diagram of a finite element method (FEM)-based anchorage zone failure mechanism analysis system provided in an embodiment of the present invention. The present invention provides an FEM-based anchorage zone failure mechanism analysis system 200, comprising: a parameter acquisition module 210, a parameter coupling module 220, and a process determination module 230.

[0043] The parameter acquisition module 210 is configured to use a finite element model to perform local and global modeling of the anchorage zone of a multi-scale bridge expansion joint, simulate interface contact behavior, and acquire corresponding mechanical indices and damage variables. The mechanical indices include field stress and interface deformation parameters in different directions, and the damage variables include interface bond damage parameters and concrete matrix damage parameters. The parameter coupling module 220 is configured to perform correlation regression processing on each mechanical index with the interfacial bond damage parameter and the concrete matrix damage parameter to determine the correlation factors of the two types of damage parameters. Based on the correlation factors, the interfacial bond damage parameter and the concrete matrix damage parameter are coupled to obtain the comprehensive damage parameter and establish the first mapping relationship between the comprehensive damage parameter and the mechanical index. The process determination module 230 is configured to divide the comprehensive damage parameters into multiple mapping intervals with different numerical ranges. In each mapping interval, the corresponding main damage control factors are obtained to correct the first mapping relationship to obtain the target mapping relationship. Based on the target mapping relationship, the damage evolution process of the anchorage area is determined. The main damage control factors include at least one of the following: stress concentration characteristics, expansion joint type difference characteristics, additional stress characteristics, and horizontal force influence characteristics.

[0044] In some embodiments, the parameter acquisition module 210 is specifically configured as follows: Based on ANSYS finite element software, local and global models of modular, seamless, and comb-plate type expansion joints were established respectively. Solid45 solid elements were used to simulate beams, bridge deck pavement, elastic bodies, anchorage zone concrete and cross joint plates. Conta173 face-to-face contact elements and Targe170 target elements were used to simulate interface contact behavior. Multi-scale coupling of the anchorage zone was achieved through displacement boundary conditions. Different levels of load were applied to the anchorage zone to obtain the corresponding mechanical indices and damage variables.

[0045] In some embodiments, the correlation factors include a first correlation factor and a second correlation factor; the parameter coupling module 220 is specifically configured as follows: Based on the current actual bond strength and the initial design bond strength of the interface, the interface bond damage parameters are determined. Combining the interface bond damage parameters with the degree of influence of various mechanical indicators, the first correlation factor is obtained. Based on the measured strain of the concrete in the anchorage zone under the current load, the benchmark strain under the same load in the initial service state, and the ultimate failure strain of the concrete, the damage parameters of the concrete matrix are determined. Combining the damage parameters of the concrete matrix with the degree of influence of various mechanical indicators, the second correlation factor is obtained.

[0046] In some embodiments, the parameter coupling module 220 is specifically configured as follows: The first and second correlation factors are normalized to obtain the corresponding weighted contribution coefficients, and the coupling amplification coefficient is obtained by fitting the regression residuals. A damage cross-coupling term is introduced using a coupling amplification factor. Combined with interfacial bond damage parameters, concrete matrix damage parameters, and corresponding related factors, the comprehensive damage parameter is determined. The damage cross-coupling term characterizes the synergistic deterioration coupling effect between interfacial bond damage parameters and concrete matrix damage parameters.

[0047] In some embodiments, the parameter coupling module 220 is specifically configured as follows: Using the set of mechanical indices as independent variables and the comprehensive damage parameters as dependent variables, a regression model is established, and the first mapping relationship is determined by fitting the model using the least squares method.

[0048] In some embodiments, the process determination module 230 is specifically configured as follows: Based on the damage evolution process, the comprehensive damage parameters are divided into the microcrack initiation stage, the debonding and propagation stage, and the concrete spalling stage; During the microcrack initiation stage, the corresponding primary damage controlling factors are obtained; the primary damage controlling factors include stress concentration characteristics and interface shear stress. During the debonding propagation phase, the corresponding secondary damage controlling factors are obtained; the secondary damage controlling factors include interfacial shear stress, interfacial slip, and debonding area. During the concrete spalling period, the corresponding third major damage controlling factors were obtained; the third major damage controlling factors include vertical displacement and debonding area.

[0049] In some embodiments, the process determination module 230 is further configured as follows: Based on the inherent stress level differences of different types of expansion joints, a type correction coefficient is determined to correct the first mapping relationship; When fitting the first mapping function for different mapping intervals, add a continuity boundary constraint.

[0050] It should be noted that the anchorage zone failure mechanism analysis system based on finite element verification provided in this application embodiment and the anchorage zone failure mechanism analysis method based on finite element verification provided in this application embodiment are based on the same application concept. Therefore, the specific implementation of this embodiment can refer to the implementation of the aforementioned anchorage zone failure mechanism analysis method based on finite element verification, and the repeated parts will not be described again.

[0051] In some embodiments, please refer to Figure 3 , Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device 300 provided in this embodiment includes a processor 310 and a memory 320; the memory 320 stores a computer program, wherein the computer program, when executed by the processor, implements the aforementioned method for analyzing the failure mechanism of the anchorage zone based on finite element verification.

[0052] Specifically, processor 310 may include, for example, a general-purpose microprocessor, an instruction set processor and / or an associated chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. Processor 310 may also include onboard memory for caching purposes. Processor 310 may be a single processing unit or multiple processing units for performing different actions of the method flow according to embodiments of this application.

[0053] The memory 320 may be any medium capable of containing, storing, transmitting, propagating, or transmitting instructions. For example, the memory 320 may include, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, apparatuses, or propagation media. Specific examples of the memory 320 include: magnetic storage devices such as magnetic tape or hard disk drives (HDDs); optical storage devices such as optical discs (CD-ROMs); and may also be random access memory (RAM) or flash memory; and / or wired / wireless communication links.

[0054] This application also provides a non-transitory computer-readable storage medium storing a computer program thereon. When executed by a processor, this program implements the aforementioned method for analyzing the failure mechanism of the anchorage zone based on finite element verification. This computer-readable medium may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into that device / apparatus / system. The aforementioned computer-readable medium carries one or more programs, which, when executed, implement the method according to the embodiments of this application.

[0055] According to embodiments of this application, a computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wireless, wired, optical fiber, radio frequency signals, etc., or any suitable combination thereof.

[0056] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this application can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in this application. All such combinations and / or combinations fall within the scope of this application. Therefore, the scope of this application should not be limited to the above embodiments, but should be defined not only by the appended claims, but also by the equivalents of the appended claims. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the protection scope of this invention.

Claims

1. A method for analyzing the failure mechanism of the anchorage zone based on finite element verification, characterized in that, include: The finite element model is used to model the anchorage zone of a multi-scale bridge expansion joint locally and globally, simulate the interface contact behavior, and obtain the corresponding mechanical indices and damage variables. The mechanical indices include field stress and interface deformation parameters in different directions, and the damage variables include interface bond damage parameters and concrete matrix damage parameters. Each of the mechanical indices is correlated with the interfacial bond damage parameter and the concrete matrix damage parameter through correlation regression to determine the correlation factors for each of the two types of damage parameters. Based on the correlation factors, the interfacial bond damage parameter and the concrete matrix damage parameter are coupled to obtain a comprehensive damage parameter, and a first mapping relationship between the comprehensive damage parameter and the mechanical indices is established. The comprehensive damage parameters are divided into multiple mapping intervals with different numerical ranges. In each mapping interval, the corresponding main damage control factors are obtained to correct the first mapping relationship and obtain the target mapping relationship. The damage evolution process of the anchorage zone is determined based on the target mapping relationship. The main damage control factors include at least one of stress concentration characteristics, interface shear stress, interface slip, debonding area, and vertical displacement.

2. The method for analyzing the failure mechanism of the anchorage zone based on finite element verification as described in claim 1, characterized in that, The method utilizes the finite element model to perform local and global modeling of the anchorage zone of a multi-scale bridge expansion joint, simulates interface contact behavior, and obtains corresponding mechanical indices and damage variables, including: Based on ANSYS finite element software, local and global models of modular, seamless, and comb-plate type expansion joints were established respectively. Solid45 solid elements were used to simulate beams, bridge deck pavement, elastic bodies, anchorage zone concrete and cross joint plates. Conta173 face-to-face contact elements and Targe170 target elements were used to simulate interface contact behavior. Multi-scale coupling of the anchorage zone was achieved through displacement boundary conditions. Different levels of load were applied to the anchorage zone to obtain the corresponding mechanical indices and damage variables.

3. The method for analyzing the failure mechanism of the anchorage zone based on finite element verification as described in claim 1, characterized in that, The relevant factors include a first relevant factor and a second relevant factor; the step of performing correlation regression analysis on each of the mechanical indices with the interfacial bond damage parameter and the concrete matrix damage parameter to determine the relevant factors for each of the two types of damage parameters includes: Based on the current actual bond strength and the initial design bond strength of the interface, the interface bond damage parameters are determined. Combining the interface bond damage parameters with the degree of influence of the various mechanical indicators, the first correlation factor is obtained. Based on the measured strain of the concrete in the anchorage zone under the current load, the benchmark strain under the same load in the initial service state, and the ultimate failure strain of the concrete, the damage parameters of the concrete matrix are determined. Combining the damage parameters of the concrete matrix with the degree of influence of the various mechanical indices, a second correlation factor is obtained.

4. The method for analyzing the failure mechanism of the anchorage zone based on finite element verification as described in claim 3, characterized in that, The comprehensive damage parameters are obtained by coupling the interfacial bond damage parameters and the concrete matrix damage parameters based on the relevant factors, including: The first and second related factors are normalized to obtain the corresponding weighted contribution coefficients, and the coupling amplification coefficient is obtained by fitting the regression residuals. The damage cross-coupling term is introduced using the coupling amplification factor, and the comprehensive damage parameter is determined by combining the interfacial bond damage parameter, the concrete matrix damage parameter, and the corresponding related factors. The damage cross-coupling term characterizes the synergistic deterioration coupling effect between the interfacial bond damage parameter and the concrete matrix damage parameter.

5. The method for analyzing the failure mechanism of the anchorage zone based on finite element verification as described in claim 1, characterized in that, Establishing the first mapping relationship between the comprehensive damage parameters and the mechanical indices includes: Using the set of mechanical indices as independent variables and the comprehensive damage parameters as dependent variables, a regression model is established, and the model is fitted using the least squares method to determine the first mapping relationship.

6. The method for analyzing the failure mechanism of the anchorage zone based on finite element verification as described in claim 1, characterized in that, The process involves dividing the comprehensive damage parameters into multiple mapping intervals with different numerical ranges. Within each mapping interval, the corresponding main damage controlling factors are obtained to correct the first mapping relationship, resulting in a target mapping relationship. This includes: Based on the damage evolution process, the comprehensive damage parameters are divided into the microcrack initiation stage, the debonding and propagation stage, and the concrete spalling stage. During the microcrack initiation period, the corresponding first damage controlling factor is obtained; the first damage controlling factor includes stress concentration characteristics and interface shear stress. During the debonding propagation period, the corresponding second damage controlling factors are obtained; the second damage controlling factors include interfacial shear stress, interfacial slip, and debonding area. During the concrete spalling period, the corresponding third major damage control factor is obtained; the third major damage control factor includes vertical displacement and debonding area.

7. The method for analyzing the failure mechanism of the anchorage zone based on finite element verification as described in claim 6, characterized in that, The step of dividing the comprehensive damage parameters into multiple mapping intervals with different numerical ranges, and obtaining the corresponding main damage control factors in each mapping interval to correct the first mapping relationship and obtain the target mapping relationship, further includes: Based on the inherent stress level differences of different types of expansion joints, a type correction coefficient is determined to correct the first mapping relationship; When fitting the first mapping function for different mapping intervals, add a continuity boundary constraint.

8. A system for analyzing the failure mechanism of the anchorage zone based on finite element verification, characterized in that, include: The module consists of a parameter acquisition module, a parameter coupling module, and a process determination module; among them, The parameter acquisition module is configured to use a finite element model to perform local and global modeling of the anchorage zone of a multi-scale bridge expansion joint, simulate interface contact behavior, and acquire corresponding mechanical indices and damage variables. The mechanical indices include field stress and interface deformation parameters in different directions, and the damage variables include interface bond damage parameters and concrete matrix damage parameters. The parameter coupling module is configured to perform correlation regression processing on each of the mechanical indices with the interfacial bond damage parameters and the concrete matrix damage parameters to determine the correlation factors of the two types of damage parameters, and couple the interfacial bond damage parameters and the concrete matrix damage parameters based on the correlation factors to obtain a comprehensive damage parameter, and establish a first mapping relationship between the comprehensive damage parameter and the mechanical indices. The process determination module is configured to divide the comprehensive damage parameters into multiple mapping intervals with different numerical ranges, obtain the corresponding main damage control factors in each mapping interval, modify the first mapping relationship to obtain the target mapping relationship, and determine the damage evolution process of the anchorage zone based on the target mapping relationship; the main damage control factors include at least one of stress concentration characteristics, expansion joint type difference characteristics, additional stress characteristics, and horizontal force influence characteristics.

9. An electronic device, characterized in that, It includes a processor and a memory; the memory stores a computer program, wherein the computer program, when executed by the processor, implements the anchorage zone failure mechanism analysis method based on finite element verification as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium, characterized in that, It stores a computer program, wherein when the computer program is executed by a processor, it implements the anchorage zone failure mechanism analysis method based on finite element verification as described in any one of claims 1 to 7.

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