Multi-scale seismic geological disaster assessment method considering deformation field and seismic oscillation characteristics

Abstract

The invention discloses a multi-scale seismic geological disaster assessment method considering deformation fields and seismic oscillation characteristics. The method comprises the following steps: carrying out regional scale risk assessment based on deformation fields and seismic oscillation parameters; performing dynamic risk scoring of the gallery scale by taking the risk assessment result of the regional scale as a background; catastrophe process simulation is carried out on the basis of the dynamic risk score based on the gallery scale, catastrophe prediction of the site scale is carried out, and a final earthquake disaster visualization map and report are generated. According to the method, through multi-scale dynamic coupling and multi-physical field simulation, the deformation field, the seismic oscillation parameters and the numerical simulation technology are combined, the geological disaster risk under the seismic action can be more comprehensively recognized through the grading evaluation method of different scales (areas, galleries and sites), the method is suitable for different application scenes, and the method has good application prospects. And the evaluation accuracy and the engineering applicability are improved.

Description

Technical Field

[0001] The present invention belongs to the field of earthquake engineering technology, and in particular relates to a multi-scale earthquake geological disaster assessment method that takes into account deformation field and ground motion characteristics. Background Art

[0002] Traditional geohazard assessment methods primarily assess risk based on environmental factors such as topography, geomorphology, geotechnical properties, and rainfall, using empirical models or statistical analysis. These methods often lack comprehensive consideration of deformation fields and ground motion parameters, making it difficult to accurately reflect geohazard risks at different spatial scales under earthquakes. Furthermore, most current assessment methods focus on a single scale, such as regional-scale earthquake landslide susceptibility assessment or localized geohazard risk assessment along engineering corridors, lacking a unified multiscale assessment framework that can adapt to diverse scenarios. Secondly, some studies have used historical landslide data and topographic factors to train machine learning models to map regional landslide susceptibility. These limitations include insufficient consideration of deformation field information, making it difficult to dynamically assess the impact of earthquakes on landslide stability. Historical data limitations also make it difficult to predict potential future earthquake-triggered landslide risks. Furthermore, some studies have combined InSAR deformation field information with geological conditions to assess landslide susceptibility and identify potentially high-risk areas. However, these methods still have limitations: they primarily focus on deformation alone, without incorporating ground motion parameters, making it difficult to assess the underlying mechanisms of earthquake-triggered landslides. Most studies are limited to the regional scale and lack detailed analysis of engineering corridors or specific site scales.

[0003] Therefore, establishing an effective earthquake geological disaster response assessment technology that comprehensively considers the deformation field and seismic motion characteristics and conducts risk assessment at different spatial scales is an important research direction to ensure the safety of regional infrastructure and improve disaster response capabilities. Summary of the Invention

[0004] In response to the above-mentioned deficiencies in the prior art, the multi-scale earthquake geological hazard assessment method that takes into account deformation field and seismic motion characteristics provided by the present invention solves the problems of low assessment accuracy, single scale, insufficient precision, and lack of dynamic assessment capabilities in the prior art.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is: a multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics, comprising the following steps:

[0006] Conduct regional-scale hazard assessment based on deformation fields and ground motion parameters;

[0007] Conduct dynamic hazard scoring at the corridor scale based on the regional-scale hazard assessment results;

[0008] Based on the dynamic hazard scoring at the corridor scale, disaster process simulation is carried out, disaster prediction at the site scale is performed, and the final earthquake hazard visualization map and report are generated.

[0009] Furthermore, the specific method for regional-scale hazard assessment based on deformation field and ground motion parameters is as follows:

[0010] Obtain the millimeter-scale surface deformation time series, annual average deformation rate, spatial gradient, and distribution of locked segments in the fault zone in the study area; construct a regional deformation field based on the above data;

[0011] A three-dimensional ground motion parameter field including peak ground acceleration, spectral period, and Arias intensity was constructed by combining regional ground motion attenuation models, historical strong earthquake records, and fault rupture simulation results.

[0012] The weight of evidence method is used to grid-superimpose the regional deformation field and the three-dimensional seismic parameter field. The kernel density estimation method is used to establish a multi-level buffer zone along the fault zone based on the grid-superimposed data.

[0013] Establish a coupling weight model of regional deformation field and three-dimensional ground motion parameter field;

[0014] The coupled weight model of regional deformation field and three-dimensional seismic parameter field is used to evaluate the hazard of multi-level buffer zones along the fault zone, and a regional-scale hazard classification map is output.

[0015] Furthermore, the coupling weight model of the regional deformation field and the three-dimensional ground motion parameter field is:

[0016] H R =α·deformation rate+β·peak ground acceleration+γ·terrain slope+δ·lithologic fragility index

[0017] Among them, H R is the hazard score, which represents the comprehensive assessment value of the earthquake geological hazard in the study area; α is the weight coefficient of deformation rate; β is the weight coefficient of peak ground acceleration; γ is the weight coefficient of terrain slope; δ is the weight coefficient of lithologic vulnerability index; the deformation rate is obtained from the regional deformation field, and the peak ground acceleration is obtained from the three-dimensional seismic parameter field.

[0018] Furthermore, the specific methods for dynamic hazard scoring at the corridor scale based on the regional-scale hazard assessment results include:

[0019] Screening high-risk sections for deformation-seismic coupling;

[0020] Fine-tune the parameters of the high-risk sections of deformation-seismic coupling to obtain the assessment range of the corridor scale;

[0021] Perform dynamic hazard scoring on the assessment range of the corridor scale, that is, calculate the corridor hazard index CSI;

[0022] According to the corridor hazard index (CSI), natural break points are used in ArcGIS for automatic classification, and a corridor-scale hazard classification map is output.

[0023] Furthermore, the specific method for screening high-risk sections of deformation-seismic coupling is:

[0024] Based on the regional deformation field, the sliding window method combined with spatial cluster analysis was used to extract continuous sections along the engineering corridor where the deformation rate exceeded the threshold, i.e., the sections with severe deformation.

[0025] Based on the three-dimensional ground motion parameter field, the area with peak ground acceleration greater than 0.2g is identified, and the spatial intersection of this area and the segment with severe deformation is calculated to obtain the area most affected by the ground motion.

[0026] A dual-index threshold method is used to divide the areas severely affected by earthquake motion into high-risk sections for deformation-earthquake coupling, where the dual indicators include deformation rate and peak ground acceleration.

[0027] Furthermore, the parameter refinement correction is to finely adjust the relevant parameters in the high-risk section of deformation-seismic coupling, and the specific method includes:

[0028] Improve the time sampling rate to obtain the local large gradient deformation field of the corridor;

[0029] The terrain slope, elevation, and lithology are used as inputs to the terrain effect amplification model to correct the peak ground acceleration;

[0030] The directivity coefficient of ground motion is quantified by the different angles between the fault strike and the corridor;

[0031] Correction of ground motion duration using radiation pattern function.

[0032] Furthermore, the dynamic risk score calculation formula is:

[0033] CSI = deformation rate anomaly coefficient × seismic amplification coefficient × project importance weight

[0034] Among them, CSI is the corridor hazard index; the deformation rate anomaly coefficient is where v i is the deformation rate of the ith unit, is the average deformation rate of all elements in the region, σ vis the standard deviation of deformation rate; seismic amplification coefficient = terrain effect amplification model × seismic directionality coefficient; the engineering importance weights are as follows: the engineering importance weight of high-speed railways is 1.5, the engineering importance weight of highways is 1.0, and the engineering importance weight of lifeline projects is 1.3.

[0035] Furthermore, the specific methods for simulating the disaster process are as follows:

[0036] The sections with CSI>0.6 were used as the site-scale analysis objects, and a three-dimensional finite element model was established;

[0037] The unsaturated seepage model under the heavy rain condition simulated by Richards equation and the seismic duration obtained after parameter refinement are used as the input of the three-dimensional finite element model.

[0038] The limit equilibrium method and strength reduction method are used to calculate the stability coefficient of the slope under the coupled earthquake-rainfall effect. The slope state is divided into unstable, potentially unstable and stable states according to the critical threshold.

[0039] For unstable slopes, the Newmark slider calculation model is used to calculate the landslide displacement triggered by earthquakes. If the landslide displacement is greater than the displacement threshold, it means that the slope has undergone significant deformation.

[0040] PFC3D was used to simulate the destruction process of slopes with significant deformation, analyze the movement trajectory, impact energy, accumulation range, and threat to the project, and generate the final earthquake disaster visualization map and report.

[0041] The beneficial effects of the present invention are:

[0042] 1. Through multi-level data dimensionality reduction and parameter transfer at the regional scale, corridor scale, and site scale, a full-chain earthquake geological hazard analysis of the study area, from macroscopic laws to mesoscopic focus to microscopic mechanisms, is achieved. This solves the one-sidedness of single-scale evaluation using traditional technologies, and at the same time more comprehensively identifies the geological hazard risks under earthquake action, making the analysis results more accurate and reliable.

[0043] 2. By constructing a coupling weight model of the regional deformation field and the three-dimensional seismic parameter field, a joint analysis of seismic parameters and topographic and geological factors is achieved, revealing the relationship between topography and earthquakes, and enabling a more accurate assessment of seismic and geological hazards in complex terrain areas.

[0044] 3. By combining the earthquake duration and rainfall models for numerical simulation, the real-time impact of pore water pressure changes on slope stability is taken into account, and a dynamic response assessment of geological hazard risks under different working conditions is achieved.

[0045] 4. By outputting visual hazard classification diagrams at various scales, the earthquake geological hazard assessment results of the study area can be displayed more intuitively, providing a clear, intuitive and reliable basis for engineering protection, which has high practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 Schematic diagram of the process of the present invention;

[0047] Figure 2 It is a regional scale hazard classification map;

[0048] Figure 3 This is the corridor scale hazard classification map;

[0049] Figure 4 Schematic diagram of the disaster process simulation at the site scale. DETAILED DESCRIPTION

[0050] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0051] like Figure 1 As shown, in one embodiment of the present invention, a multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics includes the following steps:

[0052] S1. Regional-scale hazard assessment based on deformation fields and ground motion parameters:

[0053] Using InSAR technology, GNSS (Global Navigation Satellite System), or ground-based monitoring stations, we obtain millimeter-scale surface deformation time series, annual average deformation rate, spatial gradient, and the distribution of locked fault segments along the southeastern margin of the Qinghai-Tibet Plateau. Based on these data, we construct a regional deformation field. Millimeter-scale surface deformation monitoring can promptly detect minute displacements of mountains, slopes, and other geological features, identifying potential landslide risk areas, and helping to reveal the state of crustal movement in the study area, providing reliable data support for subsequent geological hazard assessments.

[0054] A three-dimensional seismic parameter field, including peak ground acceleration (PGA), spectral period (T), and Arias intensity (Ia), is constructed by combining a regional seismic attenuation model, historical strong earthquake records, and fault rupture simulation results. The seismic attenuation model effectively reflects how seismic motion varies with distance and magnitude, while the fault rupture simulation results demonstrate the impact of the earthquake rupture process on seismic motion. By combining these two with historical strong earthquake records, the prediction of seismic parameters is more refined and more realistically reflects the spatial distribution characteristics of seismic motion. Furthermore, through comprehensive multi-parameter evaluation, the constructed three-dimensional seismic parameter field can more comprehensively demonstrate the potential impact of earthquakes on different structures and facilities.

[0055] The weights of evidence method was used to grid-superimpose the regional deformation field and the three-dimensional seismic parameter field. The kernel density estimation method was then used to establish multi-level buffer zones (e.g., 0-5 km, 5-10 km, >10 km) along the fault zone based on the grid-superimposed data.

[0056] Establish a coupling weight model between the regional deformation field and the three-dimensional ground motion parameter field:

[0057] H R =α·deformation rate+β·peak ground acceleration+γ·terrain slope+δ·lithologic fragility index

[0058] Among them, H R is the hazard score, which represents the comprehensive assessment value of the earthquake geological hazard hazard in the study area; α is the weight coefficient of deformation rate, which represents the relative importance of deformation field in the overall assessment; β is the weight coefficient of peak ground acceleration, which represents the relative importance of seismic intensity in hazard assessment; γ is the weight coefficient of terrain slope, which represents the influence of terrain steepness on geological hazard susceptibility; δ is the weight coefficient of lithologic vulnerability index, which represents the relative influence of different lithologic types in disaster susceptibility assessment and is obtained through machine training (such as random forest); deformation rate is obtained from the regional deformation field, and peak ground acceleration is obtained from the three-dimensional seismic parameter field.

[0059] This invention innovatively proposes a coupling weight model of regional deformation field and three-dimensional seismic parameter field. Combining the deformation field and seismic parameters, it can not only provide the changes in the earth's crust before and after an earthquake, but also reflect the release and propagation of energy during an earthquake, laying a solid foundation for subsequent earthquake geological disaster assessments. Furthermore, it also provides more comprehensive data support for earthquake science research and a more scientific basis for engineering seismic design.

[0060] The coupled weight model of regional deformation field and three-dimensional seismic parameter field is used to evaluate the hazard of multi-level buffer zones along the fault zone. Based on the hazard score, the natural discontinuities of GIS tools are automatically classified and a regional-scale hazard classification map (including low, medium and high hazard levels) is output. Figure 2 shown.

[0061] S2. Conduct dynamic hazard scoring at the corridor scale based on the regional-scale hazard assessment results:

[0062] S2-1. Screening of high-risk sections for deformation-seismic coupling:

[0063] Based on the regional deformation field, a sliding window method (e.g., a window size of 5×5 pixels) combined with spatial cluster analysis is used to extract continuous sections along engineering corridors (such as roads and railways) where the deformation rate exceeds a threshold (in this example, the threshold is 5 mm / year), i.e., sections with severe deformation.

[0064] Based on the three-dimensional ground motion parameter field, the area with peak ground acceleration greater than 0.2g is identified, and the spatial intersection of this area and the segment with severe deformation is calculated to obtain the area most affected by the ground motion.

[0065] A dual-index threshold method was used to classify areas severely affected by earthquakes into high-risk zones for deformation-seismic coupling. The dual indicators include deformation rate and peak ground acceleration. Specifically, the zones are classified as follows: high-risk zone—deformation rate > 5 mm / year and peak ground acceleration > 0.3 g; medium-risk zone—deformation rate > 3 mm / year and 0.2 g ≤ PGA ≤ 0.3 g; and low-risk zone—deformation rate < 3 mm / year or PGA < 0.2 g.

[0066] S2-2. Fine-tune the parameters of the high-risk deformation-earthquake coupling section to obtain the corridor-scale assessment range:

[0067] The small baseline set SBAS-InSAR method is used to increase the temporal sampling rate to quarterly to obtain the local large gradient deformation field in the corridor;

[0068] The terrain slope, elevation, and lithology are used as inputs to the Topographic Amplification Factor (TAF) to correct the peak ground acceleration.

[0069] The directivity coefficient of ground motion is quantified by the different angles between the fault strike and the corridor;

[0070] Correction of ground motion duration using radiation pattern function.

[0071] By refining the above parameters, the interaction between seismic activity and crustal deformation can be more accurately reflected, thereby obtaining more accurate corridor assessment results. In addition, many factors need to be considered when selecting project sites in high-risk earthquake areas. The refined parameters can also help identify relatively safe areas and provide a more comprehensive reference for the site selection of major projects.

[0072] S2-3. Dynamically score the corridor-scale assessment range, i.e. calculate the corridor hazard index (CSI);

[0073] CSI = deformation rate anomaly coefficient × seismic amplification coefficient × project importance weight

[0074] Among them, CSI is the corridor hazard index; the deformation rate anomaly coefficient is where v i is the deformation rate of the ith unit, is the average deformation rate of all elements in the region, σ v is the standard deviation of deformation rate; seismic amplification coefficient = terrain effect amplification model × seismic directionality coefficient; the engineering importance weights are as follows: the engineering importance weight of high-speed railways is 1.5, the engineering importance weight of highways is 1.0 (the engineering importance weight of national highways is 1.1), and the engineering importance weight of lifeline projects is 1.3.

[0075] S2-4. Based on the corridor hazard index (CSI), natural break points are used in ArcGIS to automatically classify the corridors and output a corridor-scale hazard classification map, such as Figure 3 shown.

[0076] S3. Based on the corridor-scale dynamic hazard scoring, conduct disaster process simulation, conduct site-scale disaster prediction, and generate the final earthquake hazard visualization map and report:

[0077] The sections with CSI>0.6 were used as the site-scale analysis objects, and a three-dimensional finite element model was established;

[0078] The unsaturated seepage model simulated under heavy rain conditions using the Richards equation and the seismic duration obtained after fine-tuning parameters are used as input to the 3D finite element model. This allows the distribution and changes of pore water pressure in key layers (such as near the slip surface) to be monitored. To further refine the prediction results, the Mohr-Coulomb criterion (peak strength parameter and residual strength parameter) combined with the strain softening model can be input into the 3D finite element model to account for cumulative damage under cyclic earthquake loading and thus predict disasters.

[0079] The limit equilibrium method and strength reduction method are used to calculate the stability coefficient (Fs) of the slope under the coupled action of earthquake and rainfall. The state of the slope is divided according to the critical threshold (the critical threshold of the slope stability coefficient is generally determined based on engineering geology and research experience). The state of the slope includes unstable, potentially unstable, and stable states. In this embodiment, the specific states are divided into: if Fs ≥ 1.20, it is stable; if 1.00 ≤ Fs < 1.20, it is potentially unstable; if Fs < 1.00, it is unstable; if Fs < 1.2, further evaluation of the landslide deformation trend is required.

[0080] For unstable slopes, the Newmark slider model is used to calculate earthquake-triggered landslide displacement to determine whether the landslide will undergo significant deformation. If the landslide displacement exceeds a displacement threshold (e.g., 18 cm), it indicates that the slope has undergone significant deformation and may develop into large-scale damage, requiring failure mode simulation.

[0081] PFC3D is used to simulate the destruction process of slopes with obvious deformation, and analyze the movement trajectory, impact energy, accumulation range and threats to the project, such as Figure 4 Figures (a), (b), and (c) represent schematic diagrams of earthquake duration, while (a-1), (b-1), and (c-1) represent the slope deformation process under different earthquake durations. Figure (a-1) shows deformation of the landslide between 2 and 8 seconds after the earthquake was applied. The green material indicates the area where cracks first appear in the landslide. Once cracks appear, they rapidly expand, forming areas of concentrated tensile stress. Figure (b-1) shows that between 9 and 16 seconds, the trailing edge of the landslide rapidly cracks, shearing failure occurs at the toe of the slope. The sliding zone is now connected, and the entire landslide begins to accelerate downward and disintegrate. Figure (c-1) shows that 20 seconds later, particles at the leading edge of the landslide plunge toward the valley floor and subsequently accumulate in the river valley. By simulating the failure process of a slope undergoing significant deformation and combining theoretical analysis with field observations, we can more clearly visualize the entire process from initial deformation to final failure, understand the deformation characteristics and failure modes at different stages, and provide a more comprehensive basis for earthquake geological hazard assessment.

[0082] In summary, the present invention combines deformation fields, seismic parameters and numerical simulation technology through multi-scale dynamic coupling and multi-physical field simulation. Through a graded assessment method at different scales (regions, corridors, sites), it can more comprehensively identify the geological disaster risks under earthquake action, adapt to different application scenarios, and improve the accuracy of the assessment and engineering applicability.

Claims

1. A multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics, characterized in that: The following steps are involved: Conduct regional-scale hazard assessment based on deformation fields and ground motion parameters; Conduct dynamic hazard scoring at the corridor scale based on the regional-scale hazard assessment results; Based on the dynamic hazard scoring at the corridor scale, disaster process simulation is carried out, disaster prediction at the site scale is performed, and the final earthquake hazard visualization map and report are generated.

2. A multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics according to claim 1, characterized in that: The specific method for regional-scale hazard assessment based on deformation field and ground motion parameters is as follows: Obtain the millimeter-scale surface deformation time series, annual average deformation rate, spatial gradient, and distribution of locked segments in the fault zone in the study area; construct a regional deformation field based on the above data; A three-dimensional ground motion parameter field including peak ground acceleration, spectral period, and Arias intensity was constructed by combining regional ground motion attenuation models, historical strong earthquake records, and fault rupture simulation results. The weight of evidence method is used to grid-superimpose the regional deformation field and the three-dimensional seismic parameter field. The kernel density estimation method is used to establish a multi-level buffer zone along the fault zone based on the grid-superimposed data. Establish a coupling weight model of regional deformation field and three-dimensional ground motion parameter field; The coupled weight model of regional deformation field and three-dimensional seismic parameter field is used to evaluate the hazard of multi-level buffer zones along the fault zone, and a regional-scale hazard classification map is output.

3. The multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics according to claim 2 is characterized in that: The coupling weight model of the regional deformation field and the three-dimensional ground motion parameter field is: H R =α·deformation rate+β·peak ground acceleration+γ·terrain slope+δ·lithologic fragility index Among them, H R is the hazard score, which represents the comprehensive assessment value of the earthquake geological hazard in the study area; α is the weight coefficient of deformation rate; β is the weight coefficient of peak ground acceleration; γ is the weight coefficient of terrain slope; δ is the weight coefficient of lithologic vulnerability index; the deformation rate is obtained from the regional deformation field, and the peak ground acceleration is obtained from the three-dimensional seismic parameter field.

4. According to the multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics of claim 3, the specific method of performing corridor-scale dynamic hazard scoring based on regional-scale hazard assessment results includes: Screening high-risk sections for deformation-seismic coupling; Fine-tune the parameters of the high-risk sections of deformation-seismic coupling to obtain the assessment range of the corridor scale; Perform dynamic hazard scoring on the assessment range of the corridor scale, that is, calculate the corridor hazard index CSI; According to the corridor hazard index (CSI), natural break points are used in ArcGIS for automatic classification, and a corridor-scale hazard classification map is output.

5. According to the multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics of claim 4, the specific method of screening high-risk sections of deformation-ground motion coupling is: Based on the regional deformation field, the sliding window method combined with spatial cluster analysis was used to extract continuous sections along the engineering corridor where the deformation rate exceeded the threshold, i.e., the sections with severe deformation. Based on the three-dimensional ground motion parameter field, the area with peak ground acceleration greater than 0.2g is identified, and the spatial intersection of this area and the segment with severe deformation is calculated to obtain the area most affected by the ground motion. A dual-index threshold method is used to divide the areas severely affected by earthquake motion into high-risk sections for deformation-earthquake coupling, where the dual indicators include deformation rate and peak ground acceleration.

6. According to the multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics of claim 5, the parameter refinement correction is to finely adjust the relevant parameters in the high-risk section of deformation-ground motion coupling, and the specific method includes: Improve the time sampling rate to obtain the local large gradient deformation field of the corridor; The terrain slope, elevation, and lithology are used as inputs to the terrain effect amplification model to correct the peak ground acceleration; The directivity coefficient of ground motion is quantified by the different angles between the fault strike and the corridor; Correction of ground motion duration using radiation pattern function.

7. According to the multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics of claim 6, the dynamic risk score calculation formula is: CSI = deformation rate anomaly coefficient × seismic amplification coefficient × project importance weight in, CSI is the corridor hazard index; the deformation rate anomaly coefficient is where v i is the deformation rate of the i-th unit, is the average deformation rate of all elements in the region, σ v is the standard deviation of deformation rate; seismic amplification coefficient = terrain effect amplification model × seismic directionality coefficient; the engineering importance weights are as follows: the engineering importance weight of high-speed railways is 1.5, the engineering importance weight of highways is 1.0, and the engineering importance weight of lifeline projects is 1.

3.

8. According to the multi-scale earthquake geological hazard assessment method considering deformation field and ground motion characteristics of claim 7, the specific method for simulating the disaster process is: The sections with CSI>0.6 were used as the site-scale analysis objects, and a three-dimensional finite element model was established; The unsaturated seepage model under the heavy rain condition simulated by Richards equation and the seismic duration obtained after parameter refinement are used as the input of the three-dimensional finite element model. The limit equilibrium method and strength reduction method are used to calculate the stability coefficient of the slope under the coupled earthquake-rainfall effect. The slope state is divided into unstable, potentially unstable and stable states according to the critical threshold. For unstable slopes, the Newmark slider calculation model is used to calculate the landslide displacement triggered by earthquakes. If the landslide displacement is greater than the displacement threshold, it means that the slope has undergone significant deformation. PFC3D was used to simulate the destruction process of slopes with significant deformation, analyze the movement trajectory, impact energy, accumulation range, and threat to the project, and generate the final earthquake disaster visualization map and report.

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