CN-122017985-A - Broadband earthquake motion simulation method and system based on probability earthquake risk analysis

CN122017985ACN 122017985 ACN122017985 ACN 122017985ACN-122017985-A

Abstract

The invention discloses a broadband earthquake motion simulation method and a system based on probability earthquake risk analysis, which relate to the technical field of site vibration and comprise the steps of adopting a Chinese probability earthquake risk analysis method to carry out earthquake risk decoupling and determining a potential source vibration level and a vibration center distance of a target potential source area corresponding to the maximum contribution degree with probability significance; the method comprises the steps of calculating fault size parameters of a target potential source area based on a potential source vibration level and a preset calibration rate, calculating fault distribution parameters of the target potential source area based on the fault size parameters and a mixed vibration source model, constructing a three-dimensional calculation model by combining a three-dimensional longitudinal wave velocity model and a shallow structure model, carrying out deterministic low-frequency simulation and deterministic high-frequency simulation on the three-dimensional calculation model based on a spectral element method and a three-dimensional random finite fault method respectively, and then carrying out broadband time-course sequence synthesis to obtain a broadband earthquake motion simulation result. The invention relieves the technical problem of low accuracy of the simulation result in the prior art.

Inventors

LIU ZHONGXIAN
LI CHENGCHENG
HAN LIANG
WANG TAINING
DONG ZHENG
LIU YU
GAO ZHENTAO

Assignees

天津城建大学

Dates

Publication Date: 20260512
Application Date: 20251105

Claims (10)

1. A wideband earthquake motion simulation method based on probabilistic earthquake risk analysis, the method comprising: Based on historical geological information of a target site, performing seismic risk decoupling by adopting a Chinese probability seismic risk analysis method, and determining a target potential source area corresponding to the maximum contribution degree with probability significance and potential source magnitude and earthquake center distance of the target potential source area; Calculating fault dimension parameters of the target potential source region based on the potential source magnitude and a preset scaling rate; Calculating fault distribution parameters of the target potential source region based on the fault size parameters and the mixed seismic source model; based on the epicenter distance, the fault dimension parameter, the fault distribution parameter and the elevation information of the target potential source region, a three-dimensional longitudinal wave velocity model and a shallow structure model are combined to construct a three-dimensional calculation model of the target potential source region; Based on a spectral element method and a three-dimensional random finite fault method, respectively, carrying out deterministic low-frequency simulation and deterministic high-frequency simulation on the three-dimensional calculation model to obtain a seismic low-frequency simulation result and a seismic high-frequency simulation result; And performing broadband time-course sequence synthesis on the low-frequency simulation result and the high-frequency simulation result of the earthquake motion to obtain a broadband earthquake motion simulation result.
2. The method of claim 1, wherein the seismic risk decoupling using a chinese probabilistic seismic risk analysis method based on historical geologic information of the target site comprises: based on a Chinese probability earthquake risk analysis method and a earthquake attenuation relation model, based on a potential earthquake source region, combining historical geological information of a target site, discretizing the potential earthquake source region and taking the potential earthquake source region as a point source, and respectively calculating the overrun probability of each point source to obtain a annual overrun probability curve corresponding to the target potential source region; and carrying out probability earthquake risk decomposition on the target potential source area based on the annual overrun probability curve.
3. The method of claim 1, wherein the fault size parameters comprise a fault global size parameter and a fault local size parameter, wherein, The fault global dimension parameters include a fault area, a fault length, a fault width, and an average slip over a fault plane; The local size parameters of the fault comprise the area, the length, the width, the average sliding, the trend along coordinate and the trend along coordinate of each concave-convex body, and the trend along coordinate of the cracking starting point.
4. The method of claim 1, wherein the blended source model comprises a GP15.4 blended source model and the fault distribution parameters comprise asperity distribution, blended slip distribution, break time distribution, and rise time distribution.
5. The method of claim 1, wherein performing wideband time-series synthesis on the low-frequency simulation result and the high-frequency simulation result comprises performing wideband time-series synthesis on the low-frequency simulation result and the high-frequency simulation result with a crossover frequency of 1 Hz based on a fourth-order Butterworth filter of phase differences.
6. A broadband earthquake motion simulation system based on probability earthquake risk analysis is characterized by comprising a determination module, a first calculation module, a second calculation module, a construction module, a simulation module and a synthesis module, wherein, The determining module is used for performing seismic risk decoupling by adopting a Chinese probability seismic risk analysis method based on historical geological information of a target site, and determining a target potential source area corresponding to the maximum contribution degree with probability significance and potential source magnitude and earthquake center distance of the target potential source area; The first calculation module is used for calculating fault dimension parameters of the target potential source area based on the potential source magnitude and a preset scaling rate; The second calculation module is used for calculating fault distribution parameters of the target potential source area based on the fault size parameters and the mixed seismic source model; the construction module is used for constructing a three-dimensional calculation model of the target potential source region based on the epicenter distance, the fault size parameter, the fault distribution parameter and the elevation information of the target potential source region by combining a three-dimensional longitudinal wave velocity model and a shallow structure model; The simulation module is used for carrying out deterministic low-frequency simulation and deterministic high-frequency simulation on the three-dimensional calculation model based on a spectral element method and a three-dimensional random finite fault method respectively to obtain a seismic low-frequency simulation result and a seismic high-frequency simulation result; And the synthesis module is used for carrying out broadband time-course sequence synthesis on the earthquake motion low-frequency simulation result and the earthquake motion high-frequency simulation result to obtain a broadband earthquake motion simulation result.
7. The system of claim 6, wherein the determination module is further configured to: based on a Chinese probability earthquake risk analysis method and a earthquake attenuation relation model, based on a potential earthquake source region, combining historical geological information of a target site, discretizing the potential earthquake source region and taking the potential earthquake source region as a point source, and respectively calculating the overrun probability of each point source to obtain a annual overrun probability curve corresponding to the target potential source region; and carrying out probability earthquake risk decomposition on the target potential source area based on the annual overrun probability curve.
8. The system of claim 6, wherein the synthesizing module is further configured to perform wideband time-course sequence synthesis on the low-frequency simulation result and the high-frequency simulation result based on a fourth-order Butterworth filter of phase difference with a crossover frequency of 1 Hz.
9. An electronic device comprising a memory, a processor and a computer program stored on the memory and running on the processor, the processor implementing the method according to any one of claims 1-5 when executing the computer program.
10. A computer readable storage medium having stored therein program code which is callable by a processor to perform the method of any one of claims 1 to 5.

Description

Broadband earthquake motion simulation method and system based on probability earthquake risk analysis Technical Field The invention relates to the technical field of site vibration, in particular to a broadband earthquake motion simulation method and system based on probability earthquake risk analysis. Background The earthquake fracture zones in China are numerous, and many cities are located near faults or in the earthquake zones. The complex source rupture process may cause the seismic vibrations in the near-fault region to exhibit complex characteristics (upper disc effect, impulse effect, directional effect, etc.). Moreover, station seismic records indicate that near-fault strong earthquake is not only determined by the magnitude, but also closely related to specific site characteristics, and medium earthquake can also cause serious disasters under specific sites. Meanwhile, the earthquake motion in the near-fault area often contains high-amplitude and long-period speed pulses, so that high-rise buildings, long-span bridges and the like can enter a nonlinear response state more easily, and the materials are led to yield, structural plastic deformation and even collapse. Chinese engineering site seismic safety evaluation (GB 17741-2005), hydraulic building seismic design standard (GB 51247-2018), international national guidelines for dam seismic parameter selection, reaction spectrum of concrete hydraulic buildings and seismic analysis (EM 1110-2-605) and the like all require that for major engineering, specific seismic environments and target risk levels of sites are considered, and site-related seismic vibrations are adopted. The conventional artificial earthquake motion method based on the consistent probability spectrum is used for carrying out probability earthquake risk analysis (Probabilistic Seismic Hazard Analysis, PSHA) based on the earthquake motion attenuation relation to obtain a bedrock field consistent probability spectrum as a target spectrum, and the earthquake motion time is synthesized artificially by mathematical methods such as triangle series and the like. In addition, aiming at near fault pulse type earthquake motion, the thought of students at home and abroad is to adopt a manual synthesis method for describing the characteristics of amplitude, period, shape and the like of a speed pulse by adopting a mathematical function, such as an equivalent speed pulse model, a filtering white noise model and the like, (2) based on the existing station earthquake record, a target spectrum with real spectrum type characteristics under the target earthquake risk level is constructed according to PSHA and a set earthquake decomposition result while considering structural characteristics and earthquake risks, such as a Conditional Mean Spectrum (CMS), a Conditional Spectrum (CS) and the like, and (3) a earthquake motion simulation method based on a physical method, such as a Spectrum Element Method (SEM), a Boundary Element Method (BEM), a Finite Element Method (FEM), a Finite Difference Method (FDM), a broadband mixing method and the like. Both of the above methods are based on PSHA probabilistic dangerous methods, which are formally compliant with regulatory requirements, but have some drawbacks. The first method can calculate a consistent hazard spectrum (UHS) of a specific place by considering the historical earthquake and the potential earthquake source area distribution and rule, but the UHS has envelope characteristics of earthquake response spectrums of different earthquake magnitudes M and earthquake center distances R, and the result is usually larger. The artificially synthesized earthquake motion part has certain limitations in simulating the near fault effect, considering the specific local site conditions and the pulse parameters of the engineering site. The CMS/CS can overcome the defect of the consistent probability spectrum to a certain extent, but due to the limited recorded data of the existing station, in the record selection facing the anti-seismic specification, factors such as a fracture mechanism, faults, paths and directivities of seismic waves cannot be considered finely, otherwise, the wave selection flow Cheng Hui is very complex, so that the number of the selected strong-seismic records is also relatively rare. At present, the seismic nonlinear effect of a sedimentary layer is rarely studied, the effective simulation frequency is mostly low, but the actual near-fault seismic frequency band is wider, and the general engineering seismic design is designed to fully consider the influence of a high-order vibration mode, so that the effective frequency needs to reach 10-20 Hz. However, the current vibration simulation frequency range from fracture dynamic fracture to field reaction of the whole physical process is mostly limited to below 5 Hz. Random finite fault (EXSIM), theory is easy to understand, and calculation speed is high, and the method is proved to be a relati