Method and system for analyzing vulnerability of subway station in complex site based on CPSHA

Abstract

The invention discloses a CPSHA-based complex site subway station vulnerability analysis method and system, and relates to the technical field of seismology, and the method comprises the steps: carrying out the seismic risk decoupling of a target research region based on a Chinese probability seismic risk analysis method, and determining the magnitude and epicentral distance of a plurality of seismic events with probability significance in the target research region; simulating by adopting a kinematics mixed seismic source model of fault physical fracture to obtain a broadband seismic oscillation simulation result; through SEM-3DEXSIM-FEM coupling, a broadband seismic oscillation simulation result is converted into seismic oscillation input of a subway structure close to the fault liquefaction site; modeling the target subway station and the station interval tunnel of the target subway station, and performing earthquake damage simulation analysis; and carrying out improved underground structure true vulnerability analysis based on actual site annual exceeding probability seismic oscillation. According to the invention, the technical problem of insufficient accuracy in the prior art is relieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of seismology, in particular to a CPSHA complex site-based subway station vulnerability analysis method and system. BACKGROUND

[0002] Due to the complex geological environment (active faults, soft soil) and multiple construction constraints, it is difficult for many key cities in China to completely avoid active faults, resulting in serious seismic disaster risks for existing subway lines, and strong earthquakes may cause serious disaster losses.

[0003] Near-fault ground motion is much stronger than the specification due to the rupture effect (velocity pulse, large displacement), posing a greater threat to near / fault-crossing subway tunnels and causing nonlinear damage. The main causes of seismic damage are: ① near-fault strong ground motion effects (such as velocity pulse); ② earthquake secondary disasters (fault displacement, permanent deformation of the site). The traditional incremental dynamic analysis method (IDA) based on structure vulnerability calculation method has the technical problem of insufficient accuracy. SUMMARY

[0004] In order to solve the above technical problems existing in the prior art, the embodiments of the present application provide a CPSHA complex site-based subway station vulnerability analysis method and system. The technical solution is as follows:

[0005] On the one hand, a CPSHA complex site-based subway station vulnerability analysis method is provided, which is applied to a target subway station; the method comprises: decoupling the seismic hazard of a target research area based on a Chinese probability seismic hazard analysis method, determining the magnitude and epicentral distance of a plurality of seismic events with a probability significance in the target research area; based on the magnitude and epicentral distance of the plurality of seismic events, a kinematic hybrid source model of fault physical rupture is used for simulation to obtain wide-frequency ground motion simulation results; the wide-frequency ground motion simulation results are converted into near-fault liquefied site subway structure ground motion input through SEM-3D EXSIM-FEM coupling; the target subway station and the station interval tunnel of the target subway station are modeled, and seismic damage simulation analysis is performed based on the near-fault liquefied site subway structure ground motion input to obtain simulation analysis results; the analysis results are subjected to improved underground structure true vulnerability analysis based on actual site annual exceedance probability ground motion to obtain vulnerability analysis results.

[0006] Optionally, the seismic risk of a target research region is decoupled based on a Chinese probabilistic seismic risk analysis method to determine the magnitude and epicentral distance of a plurality of seismic events in the target research region in a probabilistic sense, including: based on a Chinese probabilistic seismic risk analysis calculation framework of the target research region, adopting a three-level basic potential seismic source division scheme, and introducing a preset spatial function to describe the non-uniformity of seismic activity in different potential seismic source areas in a seismic statistical area; based on the Chinese probabilistic seismic risk analysis method and a preset ground motion attenuation relationship model, dividing the seismic activity of a seismic belt in the target research region into each potential seismic source area in the seismic belt, discretizing the potential seismic source areas into grids and regarding them as point sources, and respectively calculating the exceedance probability of each point source; based on the influence and contribution value of the seismic statistical area in the target research region on the site of the target subway station, obtaining the exceedance probability at the site of the target subway station; based on the results of the Chinese probabilistic seismic risk analysis, discretizing all contributing magnitude and epicentral distance combinations of the ground motion parameters at the site of the target subway station, and calculating the contribution proportion of each magnitude and epicentral distance combination, and through setting the seismic decoupling calculation, selecting the magnitude and corresponding epicentral distance with the maximum exceedance probability.

[0007] Optionally, based on the magnitude and epicentral distance of the plurality of seismic events, a kinematic hybrid source model of fault physical rupture is used for simulation to obtain a broadband ground motion simulation result, including: based on the magnitude of the plurality of seismic events and a preset reference rate, a finite fault concave-convex body model is established; based on the finite fault concave-convex body model and a hybrid source model, a kinematic hybrid source model is established; based on the epicentral distance, the finite fault concave-convex body model, the kinematic hybrid source model and the elevation information of the target research region, a three-dimensional calculation model is constructed in combination with a three-dimensional P-wave velocity model and a Chinese mainland shallow structure model; respectively based on a spectral element method and a three-dimensional stochastic finite fault method, deterministic low-frequency simulation and deterministic high-frequency simulation are performed on the three-dimensional calculation model to obtain ground motion low-frequency simulation results and ground motion high-frequency simulation results; the ground motion low-frequency simulation results and the ground motion high-frequency simulation results are synthesized in a broadband time sequence to obtain a broadband ground motion simulation result.

[0008] Optionally, the broadband ground motion simulation result is converted into near-fault liquefied site subway structure ground motion input through SEM-3DEXSIM-FEM coupling, including: based on an artificial boundary substructure, SEM-3DEXSIM-FEM coupling is performed to convert the broadband ground motion simulation result into near-fault liquefied site subway structure ground motion input.

[0009] Optionally, the analysis result is subjected to an improved true seismic vulnerability analysis of underground structure based on actual site annual exceedance probability ground motion, to obtain a vulnerability analysis result, including: based on a component-system double-level damage criterion, taking the analysis result as input, statistically analyzing structure damage state through nonlinear dynamic analysis, constructing a damage probability matrix and converting it into a site-specific vulnerability matrix, and finally deriving a true site seismic vulnerability curve and distribution rule as the vulnerability analysis result.

[0010] In another aspect, a CPSHA complex site subway station vulnerability analysis system based on the CPSHA complex site subway station vulnerability analysis method is also provided, and is applied to a target subway station; the system is used to implement the CPSHA complex site subway station vulnerability analysis method; the system includes a determination module, a simulation module, a coupling module, a first analysis module and a second analysis module; the determination module is used to decouple seismic hazard of a target research region based on a Chinese probability seismic hazard analysis method, and determine magnitudes and epicentral distances of a plurality of seismic events with a probability significance in the target research region; the simulation module is used to simulate based on the magnitudes and epicentral distances of the plurality of seismic events, to obtain wide-frequency ground motion simulation results by using a kinematic hybrid source model of fault physical rupture; the coupling module is used to convert the wide-frequency ground motion simulation results into near-fault liquefied site subway structure ground motion input by SEM-3D ESM-FEM coupling; the first analysis module is used to model the target subway station and a station interval tunnel of the target subway station, and perform seismic damage simulation analysis based on the near-fault liquefied site subway structure ground motion input, to obtain simulation analysis results; and the second analysis module is used to perform an improved true seismic vulnerability analysis of underground structure based on actual site annual exceedance probability ground motion on the analysis result, to obtain a vulnerability analysis result.

[0011] Optionally, the determining module is further configured to: based on a China probability seismic risk analysis calculation framework of a target research region, adopt a three-level basic potential seismic source region division scheme, and describe the non-uniformity of seismic activity in different potential seismic source regions in a seismic statistical region by introducing a preset spatial function; based on a China probability seismic risk analysis method and a preset ground motion attenuation relationship model, divide the seismic activity of a seismic belt in the target research region into each potential seismic source region in the seismic belt, discretize the potential seismic source regions into grids and regard them as point sources, and respectively calculate the exceedance probability of each point source; based on the influence and contribution value of a seismic statistical region in the target research region on a site point where the target subway station is located, obtain the exceedance probability of the site point where the target subway station is located; and based on the result of the China probability seismic risk analysis, discretize all the contributing magnitude and epicentral distance combinations of the ground motion parameters at the site point where the target subway station is located, calculate the contribution proportion of each magnitude and epicentral distance combination, and select the magnitude and corresponding epicentral distance with the maximum exceedance probability through setting seismic decoupling calculation.

[0012] Optionally, the simulating module is further configured to: based on the magnitude of the plurality of seismic events and a preset reference rate, establish a finite fault concave-convex body model; based on the finite fault concave-convex body model and a hybrid source model, establish a kinematic hybrid source model; based on the epicentral distance, the finite fault concave-convex body model, the kinematic hybrid source model, and the elevation information of the target research region, construct a three-dimensional calculation model in combination with a three-dimensional P-wave velocity model and a China mainland shallow structure model; based on a spectral element method and a three-dimensional stochastic finite fault method respectively, perform deterministic low-frequency simulation and deterministic high-frequency simulation on the three-dimensional calculation model to obtain ground motion low-frequency simulation results and ground motion high-frequency simulation results; and perform wide-band time history synthesis on the ground motion low-frequency simulation results and the ground motion high-frequency simulation results to obtain wide-band ground motion simulation results.

[0013] In another aspect, an electronic device is provided, which includes a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor implements the method provided by the embodiments of the present application when executing the computer program.

[0014] In another aspect, a computer readable storage medium is provided, which stores program code, and the program code can be invoked by a processor to execute the method provided by the embodiments of the present application.

[0015] The embodiment of the present application provides a kind of based on CPSHA complex site subway station vulnerability analysis method and system, the innovative method of fusion probability seismic risk assessment and physical rupture process simulation, accurately characterizes near-fault effect and local site condition, reveals the mechanism of disaster of subway tunnel under different fortification levels, alleviate the technical problem of lack of accuracy existing in prior art. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0017] Figure 1 It is a flowchart of a CPSHA complex site subway station vulnerability analysis method provided by the embodiment of the present application; Figure 2 It is a schematic diagram of probability seismic risk decomposition result under different fortification levels provided by the embodiment of the present application; Figure 3 It is a schematic diagram of kinematic hybrid source model of fault physical rupture provided by the embodiment of the present application; Figure 4 It is a schematic diagram of radial component (FN) broadband ground motion simulation result provided by the embodiment of the present application; Figure 5 It is a schematic diagram of tangential component (FP) broadband ground motion simulation result provided by the embodiment of the present application; Figure 6 It is a schematic diagram of vertical component (UD) broadband ground motion simulation result provided by the embodiment of the present application; Figure 7 It is a schematic diagram of SEM-3DEXSIM-FEM coupling to realize complex site subway structure seismic input provided by the embodiment of the present application; Figure 8 It is a specific implementation step diagram of SEM-3DEXSIM-FEM coupling artificial boundary substructure provided by the embodiment of the present application; Figure 9 It is a schematic diagram of subway station model provided by the embodiment of the present application; Figure 10 It is a schematic diagram of station interval tunnel model provided by the embodiment of the present application; Figure 11 It is a schematic diagram of real site seismic vulnerability curve and distribution law provided by the embodiment of the present application; Figure 12A schematic diagram of a CPSHA complex site subway station vulnerability analysis system is provided in the embodiments of the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the present application will be described below with reference to the drawings.

[0019] In the embodiments of the present application, the words such as "example", "for example" are used to represent an example, illustration or description. Any embodiment or design scheme described as "example" in the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the word "example" is intended to present the concept in a specific manner. In addition, in the embodiments of the present application, the meaning expressed by "and / or" can be both, or can be either one of the two.

[0020] To make the technical problems, technical solutions and advantages of the present application clearer, the following will be described in detail with reference to the drawings and specific embodiments.

[0021] Figure 1 A flowchart of a CPSHA complex site subway station vulnerability analysis method is provided in the embodiments of the present application, and the method is applied to a target subway station. As shown in Figure 1 , the method specifically includes the following steps:

[0022] Step S102, decoupling the seismic risk of a target research area based on the Chinese probabilistic seismic risk analysis method, and determining the magnitude and epicentral distance of a plurality of seismic events with a probabilistic sense in the target research area.

[0023] Step S104, based on the magnitude and epicentral distance of the plurality of seismic events, using a kinematic hybrid source model of fault physical rupture to simulate, obtaining wide-frequency ground motion simulation results.

[0024] Step S106, converting the wide-frequency ground motion simulation results into near-fault liquefied site subway structure ground motion input through SEM-3D EXSIM-FEM coupling.

[0025] Step S108, modeling the target subway station and the station interval tunnel of the target subway station, and performing seismic damage simulation analysis based on the near-fault liquefied site subway structure ground motion input, obtaining simulation analysis results.

[0026] Step S110, performing improved underground structure true vulnerability analysis based on actual site annual exceedance probability ground motion on the analysis results, obtaining vulnerability analysis results.

[0027] Specifically, step S102 further includes the following steps: Step S1021, based on the framework of the target research area's Chinese probabilistic seismic hazard analysis, a three-level basic potential seismic source zoning scheme is adopted, and a preset spatial function is introduced to describe the non-uniformity of seismic activity in different potential seismic source zones in the seismic statistical zone; Step S1022, based on the Chinese probabilistic seismic hazard analysis method and the preset ground motion attenuation relationship model, the seismic activity of the seismic belt in the target research area is divided into each potential seismic source zone in the seismic belt, each potential seismic source zone is discretized into a grid and regarded as a point source, and the exceeding probability of each point source is calculated respectively; Step S1023, based on the influence and contribution value of the seismic statistical zone in the target research area on the site point of the target subway station, the exceeding probability of the site point of the target subway station is obtained; Wherein, if the annual average exceeding probability of the known earthquake is known, the exceeding probability of the year in the time period can be calculated according to the principle that the earthquake time follows the mutual independence principle; Step S1024, based on the results of the Chinese probabilistic seismic hazard analysis, all contributing magnitude and epicentral distance combinations of the ground motion parameters at the site point of the target subway station are discretized, and the contribution proportion of each magnitude and epicentral distance combination is calculated, and the maximum exceeding probability is selected from the magnitude and the corresponding epicentral distance through the set earthquake decoupling calculation.

[0028] Specifically, the Chinese probabilistic seismic hazard (CPSHA) adopts a three-level basic potential seismic source zoning scheme under the similar overall theoretical framework of the probabilistic seismic hazard (PSHA), and introduces a spatial distribution function to describe the non-uniformity of seismic activity in different potential seismic source zones in the seismic statistical zone. In CPSHA, the probability that a magnitude earthquake occurs in the i-th potential seismic source zone, if the area of the i-th potential seismic source zone is ,then the probability that a magnitude earthquake occurs in each point in the i-th potential seismic source zone is

[0029]

[0030] Wherein, is the number of seismic statistical zones; is the number of seismic magnitude grades; is the number of potential seismic source zones in the k-th seismic statistical zone. is the seismic statistical zone magnitude probability density distribution function:

[0031]

[0032] and ​Upper and lower limits of magnitude of earthquake statistics region respectively, is to disperse the magnitude into magnitude grades, is the center value of the jth magnitude grade, is calculated by the magnitude interval.

[0033] Based on CPSHA theory, by using the latest seismic attenuation relationship model suitable for the study of site, using ArcGIS software, taking potential seismic source region as the basic unit, the seismic activity of the seismic belt is divided into each potential seismic source region in the seismic belt, then the potential seismic source region is dispersed into 2km 2km grid and regarded as point source, finally the exceeding probability of each point source is calculated based on Python programming.

[0034] By analyzing different seismic statistics regions in the study area, considering the influence on the site, the exceeding probability of the site is obtained :

[0035] Based on the assumption that the seismic events are independent of each other, the exceeding probability in a specific time period years can be calculated :

[0036] Based on the above analysis results, all M-R combinations contributing to the calculation of the site seismic parameters are dispersed, and the contribution proportion of each combination is calculated, the expression is:

[0037] In the formula, is the joint probability distribution of the combination when the seismic intensity parameter is greater than ; is the annual exceeding probability of the seismic intensity parameter, is the annual exceeding probability of when the magnitude is and the distance is r.

[0038] Figure 2 is the probability seismic hazard decomposition result schematic diagram under different fortification levels provided by the embodiment of the present application. As shown in Figure 2 , after determining the site peak acceleration corresponding to the fortification probability level based on CPSHA, the potential seismic source (the magnitude and the epicentral distance of the potential seismic source meet the peak acceleration requirement) is calculated by setting the seismic decoupling.​The occurrence probabilities of the combinations of the earthquake magnitudes and the epicenter distances are all lower than the fortification probability level and are different from each other. Therefore, the selection of the earthquake should follow the principle of the maximum occurrence probability, that is, from all the candidate seismic sources that can generate a peak ground acceleration A≥a at the site, the combination of the earthquake magnitude M and the epicenter distance R with the maximum occurrence probability is selected as the set earthquake parameters.

[0039] So far, the earthquake magnitude M and the corresponding epicenter distance R with the probabilistic significance under the risk level of any return period / fortification level of the research area can be obtained.

[0040] Specifically, the step S104 further includes the following steps. Step S1041, establishing a finite fault asperity model based on the earthquake magnitudes of the plurality of seismic events and the preset calibration rate.

[0041] Specifically, the finite fault asperity model includes global fault size parameters and local fault size parameters; wherein the global fault size parameters include a rupture area, a rupture length, a rupture width and an average slip on the fault plane; and the local fault size parameters include an area, a length, a width, an average slip, a strike coordinate and a dip coordinate of each asperity, and a strike coordinate and a dip coordinate of a rupture initiation point.

[0042] Step S1042, establishing a kinematic hybrid source model based on the finite fault asperity model and the hybrid source model.

[0043] Specifically, the hybrid source model includes a GP15.4 hybrid source model; and the kinematic hybrid source model includes asperity distribution, hybrid slip distribution, rupture time distribution and rise time distribution. The kinematic hybrid source model is as shown in Figure 2 .

[0044] Specifically, the finite fault asperity model is established based on the calibration rate of Jiang Wei, including global and local source parameters, considering the complexity of the fault rupture model and the uncertainty of the entire spatio-temporal evolution of the rupture, the slip distribution of the hybrid source model is calculated based on the asperity source data, and the rupture time value, the earthquake rupture time distribution and the final rise time distribution are obtained. Thus, the establishment of the hybrid source model is completed.

[0045] Step S1043, constructing a three-dimensional calculation model based on the epicenter distance, the finite fault asperity model, the kinematic hybrid source model and the elevation information of the target research area, combining a three-dimensional P-wave velocity model and a Chinese mainland shallow structure model.

[0046] Step S1044, respectively based on the spectral element method and the three-dimensional stochastic finite fault method, performing deterministic low-frequency simulation and deterministic high-frequency simulation on the three-dimensional calculation model to obtain low-frequency simulation results and high-frequency simulation results of ground motion.

[0047] Specifically, the low-frequency seismic motion simulation is performed by using a SPEED open source program developed by Politecnico di Milano, Italy. The program is based on the spectral element method, can simulate linear and nonlinear elastic wave propagation processes, and supports coupling analysis of source characteristics, propagation path effects and complex site conditions through a kinematic hybrid source model.

[0048] The high-frequency seismic motion simulation applies a three-dimensional random finite fault method 3D-EXSIM, and sets source parameters, propagation path parameters and site effect parameters of a rare earthquake under the earthquake for the target site based on empirical statistics and related research results.

[0049] In step S1045, the low-frequency seismic motion simulation result and the high-frequency seismic motion simulation result are combined to obtain a wideband seismic motion simulation result.

[0050] Specifically, the low-frequency seismic motion simulation result and the high-frequency seismic motion simulation result are combined by a phase difference-based fourth-order Butterworth filter with 1 Hz as the cross frequency.

[0051] Figure 3 A schematic diagram of a kinematic hybrid source model of fault physical rupture is provided according to an embodiment of the present application. The low-frequency part uses the spectral element method to simulate the dynamic rupture physical process of the finite fault, and the high-frequency part uses the random finite fault method.

[0052] Specifically, the low-frequency part (≤1HZ) uses the spectral element method (SEM), and the SPEED open source program based on the SEM is used to simulate the physical process of the dynamic rupture of the finite fault, because it can consider linear and nonlinear elastic seismic motion propagation, and thus the whole process of the fault rupture-propagation path-complex site effect can be simulated. The high-frequency part (>1HZ) uses the random finite fault method (3D-EXSIM), and a three-dimensional (two horizontal and one vertical) seismic motion simulation random finite fault method developed by Wang Hongwei et al. is used. The three-component results obtained by the method are finally connected with the three-component simulation results of the low-frequency stage. The difference between the time histories calculated by SEM and 3D-EXSIM is estimated using waveform cross-correlation. Based on the calculation results, the time history calculated by SEM is shifted to ensure that the first arrival of the shear wave calculated by the two algorithms is approximately the same, so as to ensure the consistency of the shear wave travel time and the rationality of the broadband ground motion amplitude and spectral characteristics. Finally, a single broadband time series is obtained by combining the SEM three-component and the 3D-EXSIM three-component using a fourth-order high-pass filter with the same corner frequency and attenuation, and taking f = 1 Hz as the cross-over frequency. The filter does not change the phase of the signal, which is helpful for the combination of the low-frequency components and the high-frequency components of the two algorithms, and the synthesis result is shown in FIG. 1. Figures 4-6 FIG. 1 is a schematic diagram of a broadband ground motion simulation result of a radial component (FN) according to an embodiment of the present application; Figure 4 FIG. 2 is a schematic diagram of a broadband ground motion simulation result of a tangential component (FP) according to an embodiment of the present application; Figure 5 FIG. 3 is a schematic diagram of a broadband ground motion simulation result of a vertical component (UD) according to an embodiment of the present application. Finally, the efficient hybrid simulation of near-fault broadband ground motion based on the complex source rupture physical mechanism is completed. Figure 6 Specifically, a concave-convex body model is established as a background model of East China based on the scaling rate, and the concave-convex body slip amount

[0053] is transformed into the wave number domain by two-dimensional Fourier transform to obtain a deterministic low-frequency wave number spectrum:

[0054] Considering the complexity of the fault rupture model and the uncertainty of the entire spatio-temporal evolution of the rupture, a random high-frequency wave number spectrum (containing a random phase θ representing the non-uniformity of the fault) satisfying the von Karman autocorrelation function is introduced :

[0055]

[0056] The low-frequency and high-frequency wave number spectra are fused into a hybrid wave number spectrum by a filter function F, and then inverse two-dimensional Fourier transform is performed to obtain a hybrid source model slip distribution :

[0057] The two-dimensional random wave number spectrum of the slip distribution is represented by Two two-dimensional random wave number spectra filtered using the Von Karman correlation function are generated and associated with them: ​

[0058]

[0059] will be and obtained after two-dimensional inverse Fourier transform to the spatial domain and According to the GP15.4 program, the fault rupture time and rise time distribution can be generated, and the coefficients and are set between 0-1.0, so that the rupture time disturbance and the rise time distribution are related to the local slip part.

[0060] For the rupture time, the rupture starting point is determined according to the distance of each sub-source and the background rupture velocity, and a spatial array of scaled random numbers n is used to apply a time disturbance to the rupture starting time of each sub-source to make the rupture propagate faster in high slip areas and slower in low slip areas, and finally obtain the rupture time value :

[0061] For the rise time, first scale the Gaussian random array , set the rise time of each sub-source to the square root of its slip value, and multiply it by the corresponding factor according to the depth position of the sub-source to represent the depth dependence of the rupture rise time, and then scale all sub-source rise times according to the average rise time of the fault rupture surface using a spatial array of scaled random numbers , to obtain the final rise time distribution.

[0062] Specifically, Figure 7 is a schematic diagram for realizing complex site subway structure seismic input based on SEM-3DEXSIM-FEM coupling according to an embodiment of the present application. As shown in Figure 7 , step S106 further includes: performing SEM-3DEXSIM-FEM coupling based on artificial boundary substructure in ABAQUS, converting wide-frequency seismic simulation results into near-fault liquefied site subway structure seismic input. In the physical model of SEM-3DEXSIM, the displacement time history of the monitoring point is proposed, which is converted into equivalent input seismic node load, and then applied to the local site for underground structure seismic damage simulation.

[0063] wherein, SEM-3DEXSIM-FEM coupling is a coupling process of using artificial boundary subprogram to load the wide-frequency seismic simulation results obtained by combining the spectral element method (SEM) and the random finite fault method (3D-EXSIM) into the FEM (Finite Element Model).

[0064] Figure 8 is a specific implementation step diagram of SEM-3DEXSIM-FEM coupled artificial boundary substructure provided according to an embodiment of the present application. As shown in Figure 8 , it comprises:

[0065] ① Select an artificial boundary substructure model: remove the hollow square symbol, and only keep the solid circle and hollow circle symbol, that is, an artificial boundary substructure model is obtained, as shown in the left part of Figure 6 .

[0066] ② Calculate the node free field displacement time history: extract the coordinates of the periphery (solid circle symbol) of the substructure model as the monitoring point coordinates, arrange the monitoring point coordinates to the physical model of the first part SEM-3DEXSIM, and obtain the free field displacement time history of each node of the periphery of the substructure model .

[0067] ③ Calculate the equivalent seismic input load: apply the calculated free wave field displacement time history in the physical model to all nodes of the corresponding artificial boundary substructure model, perform dynamic analysis on the substructure model, and the equivalent seismic input load can be obtained , as shown in the right part of Figure 6 .

[0068] Specifically, the step S108 further comprises: based on ABAQUS, coupling the Davidenkov constitutive model and the Bryne pore pressure increment model, developing a dynamic constitutive VUMAT subprogram capable of performing nonlinear effective stress calculation of soft soil layer and liquefiable soil layer, and based on the constitutive model, introducing the uniaxial compression and uniaxial tension damage variable formula of Mazars, developing the incremental form and cyclic accumulation process of the damage variable.

[0069] Figure 9 is a subway station model schematic diagram provided according to an embodiment of the present application, Figure 10 is a station interval tunnel model schematic diagram provided according to an embodiment of the present application. As shown in Figure 9 and Figure 10 , the subway station and its interval tunnel are modeled in ABAQUS, and based on ABAQUS, coupling the Davidenkov constitutive model and the Bryne pore pressure increment model, developing a dynamic constitutive VUMAT subprogram capable of performing nonlinear effective stress calculation of soft soil layer and liquefiable soil layer, and based on the constitutive model, introducing the uniaxial compression and uniaxial tension damage variable formula of Mazars, developing the incremental form and cyclic accumulation process of the damage variable. The incremental expression of the damage variable of the loading process is proposed:

[0070]

[0071]

[0072] where , is the material coefficient in tension, 0.7 < 1 for common concrete materials, < 1 for common concrete materials, < 1 for common concrete materials, , , is the material coefficient in compression, 1 < 1.5 for common concrete materials, < 1.5 for common concrete materials, < 1.5 for common concrete materials, . is defined as the equivalent tensile strain of the material, is defined as the equivalent compressive strain of the material, and the calculation formula is as follows:

[0073]

[0074]

[0075] where is the element strain, positive in tension and negative in compression. The meaning of the bracket is equal to the value in the bracket if it is positive, and 0 if it is negative. The total amount of damage is represented as:

[0076]

[0077] ,

[0078] where , are the weight coefficients of tensile damage and compressive damage, respectively, satisfying + = 1, are the three principal stresses of the material.

[0079] Specifically, the step S110 further comprises: based on the component-system double-level damage criterion, taking the analysis results as input, statistically analyzing the damage state of the structure through nonlinear dynamic analysis, constructing a damage probability matrix and converting it into a site-specific vulnerability matrix, and finally deriving the real site seismic vulnerability curve and distribution rule as the vulnerability analysis result, as shown in Figure 11 .

[0080] Specifically, first, according to the component failure criterion and the subway earthquake damage characteristics, a component-system double-level damage grade standard is established; second, near-fault broadband ground motion (including different annual exceedance probabilities) generated by physical rupture simulation is taken as input to carry out nonlinear dynamic time-history analysis of the station and the interval; based on the time-history results, the overall damage state of the structure is determined through key node damage statistics of the component; all working condition data are integrated to construct a damage probability matrix; finally, by using the mathematical relationship between the damage probability and the exceedance probability, the damage probability is converted into a site-specific vulnerability matrix, the seismic vulnerability curve of the real site is derived, and the distribution law is analyzed.

[0081] From the above description, the embodiment of the application provides a CPSHA complex site subway station vulnerability analysis method, which combines the innovative method of probability seismic hazard assessment and physical rupture process simulation, accurately characterizes the near-fault effect and local site conditions, reveals the disaster mechanism of the subway tunnel under different fortification levels, and solves the technical problem of insufficient accuracy in the prior art.

[0082] Figure 12 is a schematic diagram of a CPSHA complex site subway station vulnerability analysis system provided by the embodiment of the application, which is applied to a target subway station. Figure 12 As shown in the figure, the system comprises a determination module 10, a simulation module 20, a coupling module 30, a first analysis module 40 and a second analysis module 50.

[0083] Specifically, the determination module 10 is configured to decouple the seismic hazard of a target research area based on the Chinese probability seismic hazard analysis method, and determine the magnitude and epicentral distance of a plurality of seismic events with a probability significance in the target research area. The simulation module 20 is configured to simulate the kinematic hybrid source model of fault physical rupture based on the magnitude and epicentral distance of the plurality of seismic events, and obtain a broadband ground motion simulation result. The coupling module 30 is configured to convert the broadband ground motion simulation result into near-fault liquefied site subway structure ground motion input by SEM-3DEXSIM-FEM coupling. The first analysis module 40 is configured to model the target subway station and the station interval tunnel of the target subway station, and perform seismic damage simulation analysis based on the near-fault liquefied site subway structure ground motion input, to obtain a simulation analysis result. The second analysis module 50 is configured to perform improved true vulnerability analysis of underground structures based on actual site annual exceedance probability ground motion on the analysis result, to obtain a vulnerability analysis result.

[0084] Specifically, the determination module 10 is further configured to: Based on the calculation framework of the Chinese probabilistic seismic hazard analysis of the target research area, a three-level basic potential seismic source zoning scheme is adopted, and a preset spatial function is introduced to describe the unevenness of the seismic activity in different potential seismic source zones within the seismic statistical zone; Based on the Chinese probabilistic seismic hazard analysis method and the preset ground motion attenuation relationship model, the seismic activity of the seismic belt in the target research area is divided into each potential seismic source zone within the seismic belt, each potential seismic source zone is discretized into a grid and regarded as a point source, and the exceeding probability of each point source is calculated; Based on the influence and contribution value of the seismic statistical zone in the target research area on the site of the target subway station, the exceeding probability at the site of the target subway station is obtained. Based on the results of the Chinese probabilistic seismic hazard analysis, all contributing magnitude and epicentral distance combinations of the ground motion parameters at the site of the target subway station are discretized, and the contribution proportion of each magnitude and epicentral distance combination is calculated. After setting the seismic decoupling calculation, the magnitude with the maximum exceeding probability and the corresponding epicentral distance are selected.

[0085] Specifically, the simulation module 20 is also used for: Based on the magnitude of a plurality of seismic events and a preset reference rate, a finite fault concave-convex body model is established; Based on the finite fault concave-convex body model and the hybrid source model, a kinematic hybrid source model is established; Based on the epicentral distance, the finite fault concave-convex body model, the kinematic hybrid source model and the elevation information of the target research area, a three-dimensional calculation model is constructed in combination with a three-dimensional P-wave velocity model and a Chinese mainland shallow structure model; Based on the spectral element method and the three-dimensional stochastic finite fault method respectively, the three-dimensional calculation model is subjected to deterministic low-frequency simulation and deterministic high-frequency simulation, and ground motion low-frequency simulation results and ground motion high-frequency simulation results are obtained; The ground motion low-frequency simulation results and the ground motion high-frequency simulation results are subjected to wideband time history synthesis, and wideband ground motion simulation results are obtained.

[0086] Specifically, the coupling module 30 is also used for: Based on the SEM-3DEXSIM-FEM coupling of the artificial boundary substructure, the wideband ground motion simulation results are converted into near-fault liquefaction site subway structure ground motion input.

[0087] Specifically, the second analysis module 50 is also used for: based on the component-system double-level damage criterion, taking the analysis results as input, statistically analyzing the structure damage state through nonlinear dynamic analysis, constructing a damage probability matrix and converting it into a site-specific vulnerability matrix, and finally deriving the real site seismic vulnerability curve and distribution law as the vulnerability analysis result.

[0088] The application further provides an electronic device, comprising a memory, a processor and a computer program stored in the memory and running on the processor, and the processor implements the method provided by the embodiments of the application when executing the computer program.

[0089] The application further provides a computer readable storage medium, which stores program codes, and the program codes can be invoked by a processor to execute the method provided by the embodiments of the application.

[0090] It should be understood that the memory in the embodiments of the application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. The non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically EPROM (EEPROM) or a flash memory. The volatile memory can be a random access memory (RAM) used as an external cache. By way of example, but not limitation, many forms of random access memory (RAM) can be used, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM) and direct rambus RAM (DR RAM).

[0091] The above-described embodiments can be implemented in whole or in part by software, hardware (e.g., circuitry), firmware, or any combination of the three. When implemented in software, the above-described embodiments can be implemented in the form of one or more computer programs that are stored in a computer-readable storage medium. The computer-readable storage medium stores one or more computer instructions or computer programs that, when loaded into a computer, cause the computer to perform the processes or functions described in the embodiments of the present application. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable apparatus. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, such as from a website, a computer, a server, or a data center to another website, computer, server, or data center, via a wired (e.g., infrared, wireless, microwave, etc.) manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains one or more collections of available media. The available media can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium can be a solid-state disk.

[0092] It should be understood that the size of the sequence number of each process described above in various embodiments of the present application does not mean the order of execution, and the execution order of each process should be determined by its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0093] Those of ordinary skill in the art can realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be realized in electronic hardware, or a combination of computer software and electronic hardware. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Those of ordinary skill in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0094] Those of ordinary skill in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the devices, apparatuses and units described above can refer to the corresponding processes in the foregoing method embodiments, which will not be described here.

[0095] In several embodiments provided by the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the above-described apparatus embodiments are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, another division mode can be used. For example, a plurality of units or components can be combined or integrated into another device, or some features can be omitted or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0096] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place or distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0097] In addition, the functional units in each embodiment of the present application can be integrated into a processing unit, or each unit can be a physically independent unit, or two or more units can be integrated into one unit.

[0098] If the functions are realized in the form of software functional units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the part of the technical solutions that essentially contribute to the prior art can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program code storage media.

[0099] The above description is merely a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A vulnerability analysis method for subway stations in complex sites based on CPSHA, characterized in that, Applied to the target subway station; the method includes: Based on the Chinese probabilistic seismic hazard analysis method, seismic hazard decoupling is performed on the target study area to determine the magnitude and epicentral distance of multiple probabilistic seismic events in the target study area; Based on the magnitude and epicentral distance of the aforementioned multiple earthquake events, a kinematic hybrid source model of fault physical rupture was used for simulation to obtain broadband ground motion simulation results. The broadband ground motion simulation results were converted into ground motion inputs for subway structures in near-fault liquefaction sites by SEM-3DEXSIM-FEM coupling. Modeling is performed on the target subway station and the station section tunnel of the target subway station, and seismic damage simulation analysis is performed based on the seismic motion input of the subway structure near the fault liquefaction site to obtain the simulation analysis results; An improved true vulnerability analysis of underground structures based on the actual site annual exceedance probability ground motion was performed on the analysis results to obtain vulnerability analysis results.

2. The method according to claim 1, characterized in that, Based on the Chinese probabilistic seismic hazard analysis method, seismic hazard decoupling is performed on the target study area to determine the magnitude and epicentral distance of multiple probabilistically significant seismic events in the target study area, including: Based on the Chinese probabilistic seismic hazard analysis and calculation framework for the target study area, a three-level basic potential source area division scheme is adopted, and the non-uniformity of seismic activity in different potential source areas within the seismic statistical area is described by introducing a preset spatial function. Based on the Chinese probabilistic seismic hazard analysis method and the preset ground motion attenuation relationship model, the seismic activity of the seismic zone in the target study area is divided into various potential seismic source zones within the seismic zone, with the potential source zone as the basic unit. Each potential source zone is discretized into a grid and regarded as a point source, and the exceedance probability of each point source is calculated. Based on the influence and contribution of the seismic statistical zone within the target study area to the site where the target subway station is located, the exceedance probability at the site where the target subway station is located is obtained. Based on the results of China's probabilistic seismic hazard analysis, all combinations of magnitudes and epicentral distances that contribute to the ground motion parameters at the target subway station location are discretized, and the contribution ratio of each combination of magnitude and epicentral distance is calculated. After setting up seismic decoupling calculation, the magnitude and corresponding epicentral distance with the highest exceedance probability are selected.

3. The method according to claim 1, characterized in that, Based on the magnitude and epicentral distance of the aforementioned multiple earthquake events, a kinematic hybrid source model of fault physical rupture was used for simulation to obtain broadband ground motion simulation results, including: Based on the magnitudes and preset calibration rates of the aforementioned multiple earthquake events, a finite fault concavity / convexity model is established; Based on the aforementioned finite fault concavity / convexity model and hybrid source model, a kinematic hybrid source model is established. Based on the epicentral distance, the finite fault concave-convex body model, the kinematic hybrid source model, and the elevation information of the target study area, a three-dimensional calculation model is constructed by combining the three-dimensional longitudinal wave velocity model and the shallow structure model of the Chinese mainland. Based on the spectral element method and the three-dimensional stochastic finite fault method, deterministic low-frequency simulation and deterministic high-frequency simulation are performed on the three-dimensional calculation model to obtain the low-frequency simulation results and high-frequency simulation results of ground motion. The low-frequency and high-frequency ground motion simulation results are combined using a broadband time sequence to obtain broadband ground motion simulation results.

4. The method according to claim 1, characterized in that, The broadband ground motion simulation results are converted into ground motion inputs for subway structures in near-fault liquefaction sites through SEM-3DEXSIM-FEM coupling, including: SEM-3DEXSIM-FEM coupling based on artificial boundary substructures to convert the broadband ground motion simulation results into ground motion inputs for subway structures in near-fault liquefaction sites.

5. The method according to claim 1, characterized in that, The analysis results are used to perform an improved true vulnerability analysis of underground structures based on the actual site's annual exceedance probability ground motion. The vulnerability analysis results include: based on the component-system two-level failure standard, using the analysis results as input, nonlinear dynamic analysis is used to statistically analyze the structural damage state, construct a failure probability matrix and convert it into a site-specific vulnerability matrix, and finally derive the actual site seismic vulnerability curve and distribution pattern as the vulnerability analysis results.

6. A vulnerability analysis system for subway stations in complex sites based on CPSHA, characterized in that, Applied to the target subway station; This system is used to implement the CPSHA-based vulnerability analysis method for subway stations in complex sites as described in any one of claims 1-5; the system includes: a determination module, a simulation module, a coupling module, a first analysis module, and a second analysis module; wherein... The determination module is used to decouple the seismic hazard of the target study area based on the Chinese probabilistic seismic hazard analysis method, and determine the magnitude and epicentral distance of multiple probabilistic seismic events in the target study area. The simulation module is used to simulate the multiple earthquake events based on their magnitudes and epicentral distances using a kinematic hybrid source model of fault physical rupture, and to obtain broadband ground motion simulation results. The coupling module is used to convert the broadband ground motion simulation results into ground motion inputs for subway structures in near-fault liquefaction sites through SEM-3DEXSIM-FEM coupling. The first analysis module is used to model the target subway station and the station section tunnel of the target subway station, and to perform seismic damage simulation analysis based on the seismic motion input of the subway structure near the fault liquefaction site, and to obtain the simulation analysis results; The second analysis module is used to perform an improved true vulnerability analysis of underground structures based on the actual site's annual exceedance probability ground motion, and obtain vulnerability analysis results.

7. The system according to claim 6, characterized in that, The determining module is further configured to: Based on the Chinese probabilistic seismic hazard analysis and calculation framework for the target study area, a three-level basic potential source area division scheme is adopted, and the non-uniformity of seismic activity in different potential source areas within the seismic statistical area is described by introducing a preset spatial function. Based on the Chinese probabilistic seismic hazard analysis method and the preset ground motion attenuation relationship model, the seismic activity of the seismic zone in the target study area is divided into various potential seismic source zones within the seismic zone, with the potential source zone as the basic unit. Each potential source zone is discretized into a grid and regarded as a point source, and the exceedance probability of each point source is calculated. Based on the influence and contribution of the seismic statistical zone within the target study area to the site where the target subway station is located, the exceedance probability at the site where the target subway station is located is obtained. Based on the results of China's probabilistic seismic hazard analysis, all combinations of magnitudes and epicentral distances that contribute to the ground motion parameters at the target subway station location are discretized, and the contribution ratio of each combination of magnitude and epicentral distance is calculated. After setting up seismic decoupling calculation, the magnitude and corresponding epicentral distance with the highest exceedance probability are selected.

8. The system according to claim 6, characterized in that, The simulation module is also used for: Based on the magnitudes and preset calibration rates of the aforementioned multiple earthquake events, a finite fault concavity / convexity model is established; Based on the aforementioned finite fault concavity / convexity model and hybrid source model, a kinematic hybrid source model is established. Based on the epicentral distance, the finite fault concave-convex body model, the kinematic hybrid source model, and the elevation information of the target study area, a three-dimensional calculation model is constructed by combining the three-dimensional longitudinal wave velocity model and the shallow structure model of the Chinese mainland. Based on the spectral element method and the three-dimensional stochastic finite fault method, deterministic low-frequency simulation and deterministic high-frequency simulation are performed on the three-dimensional calculation model to obtain the low-frequency simulation results and high-frequency simulation results of ground motion. The low-frequency and high-frequency ground motion simulation results are combined using a broadband time sequence to obtain broadband ground motion simulation results.

9. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor, when executing the computer program, implements the method as described in any one of claims 1-5.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium contains program code that can be invoked by a processor to execute the method as described in any one of claims 1 to 5.

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