A method for evaluating influence of near-field active fault on tunnel surrounding rock

Abstract

The application discloses a kind of near-field active fault influence evaluation method to tunnel surrounding rock, belong to geological technical method field, including the following steps: collecting active fault area data;Determine the region needing to adjust and draw using multi-source satellite remote sensing;Using unmanned aerial vehicle oblique photography forms the geological map of adjustment and drawing;Physical field map is prepared using aerial object;Determine engineering hydrology condition;Determine the time history record of ground motion of earthquake event;Build the intersection model of tunnel and the active fault area, using non-continuous deformation method simulation analysis tunnel surrounding rock state, to evaluate the surrounding rock state.The application provides a kind of near-field active fault influence evaluation method to tunnel surrounding rock, can adapt to the accurate monitoring of large range active fault area, is less influenced by topography, field operation danger coefficient is low, and can possibly reduce artificial exploration, significantly increase work efficiency, realize the accurate evaluation of the influence of active fault to tunnel surrounding rock stability.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of geological technology methods, and particularly relates to a method for evaluating the influence of near-field active faults on tunnel surrounding rock. BACKGROUND

[0002] Active fault refers to a fault that has been active since the Holocene century, is currently active, and will still be active in the future. Active fault is connected with modern tectonic activity, and is a part of modern tectonic activity, closely related to modern geodynamic action, seismic activity and geological disasters.

[0003] With the in-depth development of national transportation construction, the demand for railway engineering construction in areas with complex geological conditions and active fault development is gradually increasing. According to the relevant requirements of the current standards, specifications and regulations, when the railway engineering line is difficult to avoid the active fault zone, it is usually intersected at a large angle and a short distance, and the stability of the tunnel surrounding rock affected by the active fault is evaluated based on the traditional ground survey method. However, in the area with active neotectonic movement, earthquakes occur frequently, and the topographic and geological conditions, spatial distribution and activity characteristics of the active fault are relatively complex. When the selected line interval is limited and can only be intersected at a small angle and a long distance parallel to the active fault, the traditional ground survey technology mainly based on manual interpretation, ground geophysical prospecting and drilling is greatly limited by the site topography, has low efficiency and high risk coefficient of field operation. SUMMARY

[0004] In view of one or more of the above defects or improvement needs of the prior art, the application provides a method for evaluating the influence of near-field active faults on tunnel surrounding rock, which can accurately monitor a wide range of active fault areas, has less influence on topography, has low risk coefficient of field operation, can reduce manual exploration as much as possible, significantly improves work efficiency, and realizes accurate evaluation of the influence of active faults on the stability of tunnel surrounding rock.

[0005] To achieve the above purpose, the application provides a method for evaluating the influence of near-field active faults on tunnel surrounding rock,

[0006] S1, collecting active fault area data, wherein the active fault area data includes regional historical seismic motion record data;

[0007] S2, interpreting the active fault area by using multi-source satellite remote sensing to obtain remote sensing information, and verifying the active fault area data according to the remote sensing information to determine the area to be interpreted.

[0008] S3, collecting image information in the area to be interpreted by using a UAV oblique photography, and interpreting the interpretation to form an interpreted geological map according to the image information;

[0009] S4, collecting geophysical field data of the active fault region by using aerial objects and / or ground object exploration, and preparing a physical field map according to the geophysical field data;

[0010] S5, determining the engineering and hydrogeological conditions and major geological feature points of the active fault region according to the active fault region data obtained in steps S1-S4, the adjusted geological map and the physical map, and performing drilling verification operation on the major geological feature points to supplement the engineering and hydrogeological conditions;

[0011] S6, analyzing the active fault region data obtained in steps S1-S5, the adjusted geological map, the physical map and the engineering and hydrogeological condition analysis to determine the regional geological conditions, spatial distribution and activity of the active fault region;

[0012] S7, synthesizing the ground motion time history record of each seismic event in the active fault region by using ground motion simulation technology according to the regional geological conditions, spatial distribution, activity and regional historical seismic record data;

[0013] S8, constructing a tunnel and the active fault region intersection model, simulating and analyzing the seismic response and damage evolution law of the tunnel surrounding rock under different action conditions by using the non-continuous deformation method, and evaluating the influence of the active fault region on the tunnel surrounding rock.

[0014] As a further preferred embodiment of the present application, the active fault region data further comprises regional geological data.

[0015] As a further preferred embodiment of the present application, in step S2, the multi-source satellite remote sensing is to observe the active fault region by using satellite-mounted optical sensors, thermal infrared sensors and microwave sensors to obtain multi-source remote sensing image data of the active fault region.

[0016] As a further preferred embodiment of the present application, step S3 comprises the following steps:

[0017] S31, collecting image information in the adjusted region by using unmanned aerial vehicle oblique photography;

[0018] S32, establishing a real scene three-dimensional model according to the image information;

[0019] S33, combining the real scene three-dimensional model with remote sensing information, virtually depicting on the real scene three-dimensional model, and determining feature points that need to be manually adjusted and verified;

[0020] S34, manually adjusting and verifying the feature points on site to form an adjusted geological map.

[0021] As a further preferred embodiment of the present application, the airborne geophysical prospecting is to obtain the three-dimensional inversion results of the active fault region by using the airborne transient electromagnetic method and / or the airborne magnetotelluric method, and to determine the physical field data of the active fault region.

[0022] As a further preferred embodiment of the present application, the drilling verification operation comprises the following steps:

[0023] S51, drilling holes at the positions of the major geological features;

[0024] S52, actual drilling to obtain cores and related parameters thereof;

[0025] S53, conducting in-hole testing to obtain in-hole geological data;

[0026] S54, testing the cores to obtain core parameters.

[0027] As a further preferred embodiment of the present application, the seismic motion simulation technology is to use a direct method, comprising the following steps:

[0028] S711, when the frequencies are the same, assuming that one point is equal to a specified velocity response spectrum, and comparing the calculated acceleration response spectrum with the target spectrum;

[0029] S712, correcting and iteratively calculating other points that do not meet the requirements of fitting accuracy;

[0030] S713, completing the synthesis of acceleration when the fitting accuracy of the calculated response spectrum and the target response spectrum meets the requirements.

[0031] As a further preferred embodiment of the present application, the seismic motion simulation technology is to use an indirect method, comprising the following steps:

[0032] S721, calculating the corresponding power spectral density function from the response spectrum;

[0033] S722, obtaining the amplitude spectrum and the distribution of corresponding frequencies by the approximate relationship between the Fourier amplitude spectrum and the power spectrum to calculate the acceleration;

[0034] S722, iteratively correcting the amplitude spectrum according to the difference between the calculated response spectrum and the target spectrum, so that the calculated response spectrum can fit the target response spectrum and meet the accuracy requirements.

[0035] As a further preferred embodiment of the present application, in step S8, the non-continuous deformation method simulation analysis comprises the following steps:

[0036] S81, establishing a model according to the spatial distribution of the active fault region and the intersection relationship with the tunnel;

[0037] S82, grid division of the calculation unit;

[0038] S83, input of physical parameters of the model;

[0039] S84, input of boundary conditions and seismic spectrum;

[0040] S85, loading calculation;

[0041] S81, post-processing of the calculation result.

[0042] As a further preferred embodiment of the application, the loading calculation comprises the following steps:

[0043] S851, adding loading blocks around the model and applying loads of corresponding sizes on the loading blocks to form extrusion stress;

[0044] S852, symmetrically distributing the loads applied on part of the loading blocks;

[0045] S853, applying symmetric forced displacement points on the upper load loading blocks to realize one-way displacement of the loading blocks;

[0046] S854, setting the cohesion of the upper load loading blocks to be maximum to drive the blocks around the upper load loading blocks to move synchronously;

[0047] S855, adding the predicted faulting distance of the active fault to the displacement points for simulation calculation.

[0048] The above improved technical features can be combined with each other as long as they do not conflict with each other.

[0049] Overall, compared with the prior art, the above technical solutions conceived by the present application have the following beneficial effects:

[0050] (1) The method for evaluating the influence of a near-field active fault on tunnel surrounding rock, by using multi-source satellite remote sensing to interpret the active fault area to determine the area to be surveyed, and further determining the geological survey in the active fault area through unmanned aerial oblique photography, aerial objects and / or ground geophysical exploration, drilling verification operation, is less affected by the terrain, has low on-site operation risk coefficient, can reduce manual exploration as much as possible, significantly improves work efficiency, and by constructing a tunnel and active fault area intersection model, using a non-continuous deformation method to simulate and analyze the seismic response and damage evolution law of the tunnel surrounding rock under different working conditions, the influence of the active fault on the stability of the tunnel surrounding rock is accurately evaluated.

[0051] (2) The application is a kind of near-field active fault influence evaluation method for tunnel surrounding rock, which is more accurate and diverse through the seismic motion simulation basic data obtained by modern comprehensive survey means, and the simulation result is closer to the actual situation; and through the establishment of a variety of working condition high-precision numerical model, the seismic response of the tunnel surrounding rock and the damage evolution law are simulated under the condition of accurate seismic time history record, and the influence of active fault on the stability of tunnel surrounding rock is evaluated.

[0052] (3) The application is a kind of near-field active fault influence evaluation method for tunnel surrounding rock, which is accurate and widely applicable, and through the comprehensive combination of traditional ground survey means, multi-source satellite remote sensing, aerial geophysical prospecting, unmanned aerial vehicle surveying and mapping and other new technologies, the regional geological conditions, spatial distribution and activity characteristics of the active fault are more targetedly checked according to the survey process of gradually deepening from surface to point, compared with the traditional survey means, the work efficiency is improved, the topographic restriction is small, the field operation danger coefficient is reduced, the survey targeting is strengthened, and excellent economic benefits and popularization value are obtained. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1 is a flow chart of a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application;

[0054] Figure 2 is a flow chart of step S3 of a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application;

[0055] Figure 3 is a drilling verification operation flow chart in step S5 of a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application;

[0056] Figure 4 is a flow chart of direct method of seismic motion simulation in step S7 of a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application;

[0057] Figure 5 is a seismic time history record with acceleration and time as variables in a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application;

[0058] Figure 6 is a seismic time history record with acceleration and frequency as variables in a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application;

[0059] Figure 7 is a flow chart of direct method of seismic motion simulation in step S7 of a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application;

[0060] Figure 8 is a flow chart of simulation analysis of non-continuous deformation method in step S8 of a kind of near-field active fault influence evaluation method for tunnel surrounding rock in the application. DETAILED DESCRIPTION

[0061] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0062] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0063] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0064] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0065] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature is "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in horizontal height than the second feature. The first feature is "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in horizontal height than the second feature.

[0066] Embodiments:

[0067] As shown in Figures 1-8 The near-field active fault impact on tunnel surrounding rock evaluation method in the preferred embodiments of the present application can adapt to accurate monitoring of a wide range of active fault areas, is less affected by terrain, has low field operation risk coefficient, and can reduce manual exploration as much as possible, significantly improve work efficiency, and realize accurate evaluation of the impact of active faults on the stability of tunnel surrounding rock.

[0068] Specifically, as shown in Figure 1 The near-field active fault impact on tunnel surrounding rock evaluation method includes the following steps:

[0069] S1, collecting active fault area data, the active fault area data including regional historical seismic motion record data;

[0070] S2, interpreting the active fault area by using multi-source satellite remote sensing to obtain remote sensing information, and verifying the active fault area data according to the remote sensing information to determine the area to be plotted.

[0071] S3, collecting image information in the area to be plotted by using a UAV oblique photography, and interpreting the plot to form a plotted geological map according to the image information;

[0072] S4, collecting geophysical field data of the active fault area by using aerial objects and / or ground geophysical prospecting, and preparing a physical field map according to the geophysical field data;

[0073] S5, determining the engineering and hydrogeological conditions and major geological feature points of the active fault area according to the active fault area data, plotted geological map and physical map obtained in steps S1-S4, and performing drilling verification operation on the major geological feature points to supplement the engineering and hydrogeological conditions.

[0074] S6, analyzing the active fault area data, plotted geological map, physical map and engineering and hydrogeological condition analysis obtained in steps S1-S5 to determine the regional geological conditions, spatial distribution and activity of the active fault area;

[0075] S7, synthesizing the time history records of ground motion of each seismic event in the active fault region by ground motion simulation technology according to regional geological conditions, spatial distribution, activity and regional historical ground motion record data;

[0076] S8, constructing a tunnel and active fault region intersection model, simulating and analyzing the seismic response and damage evolution law of the tunnel surrounding rock under different action conditions by using the non-continuous deformation method, and evaluating the influence of the active fault region on the tunnel surrounding rock.

[0077] Further, in the preferred embodiment of the present application, the active fault region quality includes regional historical ground motion record data and regional geological data; wherein the regional geological data includes regional geological map, regional geological report (description); the regional historical ground motion record data includes regional historical earthquake source geographical position, magnitude, ground motion acceleration, etc. Preferably, the basic engineering geological profile of the active fault region is obtained by preliminary analysis of the regional geological data and the regional historical ground motion record data.

[0078] Further, in the preferred embodiment of the present application, the multi-source satellite remote sensing in step S2 is to observe the active fault region by using satellite-mounted optical sensors, thermal infrared sensors and microwave sensors, and to obtain multi-source remote sensing image data of the active fault region. Preferably, the information provided by the multi-source remote sensing image data is more diverse and sufficient, the remote sensing data of different sources can complement and verify each other, the macro geological identification and interpretation is more accurate, the high-precision image can accurately interpret the surface poor geological development, the high spectrum and multi-spectrum can realize quantitative identification of lithology, the thermal infrared can interpret the surface temperature distribution, and the DEM (Digital Elevation Model) and InSAR data can interpret the crustal movement trend and displacement amount. The multi-source remote sensing is compared and verified with the regional data, and guides the subsequent adjustment and interpretation work.

[0079] Further preferably, as shown in Figure 2 In the preferred embodiment of the present application, step S3 includes the following steps:

[0080] S31, collecting image information in the adjustment and interpretation region by using unmanned aerial vehicle oblique photography;

[0081] S32, establishing a real scene three-dimensional model according to the image information;

[0082] Preferably, the real scene three-dimensional modeling is carried out by using PHOTOSCAN software according to the depth of field, flight height and geographical coordinate information of the image record.

[0083] S33, combining the real scene three-dimensional model with the remote sensing information, virtually depicting on the real scene three-dimensional model, and determining the feature points that need to be manually adjusted and interpreted;

[0084] S34, artificial field surveying and verifying characteristic points to form a surveying and verifying geological map.

[0085] More specifically, in one preferred embodiment of the present application, the airborne geophysical prospecting in step S4 uses airborne transient electromagnetic method and / or airborne magnetotelluric method to obtain three-dimensional inversion results of the active fault region and determine the physical field data of the active fault region. The stratum, lithology, distribution and contact relationship of the regional active fault are analyzed from different perspectives of physical property parameters, spatial distribution relationship, etc.

[0086] Further, as shown in Figure 3 , in one preferred embodiment of the present application, the drilling verification operation in step S5 includes the following steps:

[0087] S51, drilling at the positions of major geological characteristic points;

[0088] S52, actual drilling to obtain cores and related parameters thereof;

[0089] S53, conducting in-hole testing to obtain in-hole geological data;

[0090] Preferably, the in-hole geological data includes resistivity, ground stress, permeability coefficient and shear wave velocity.

[0091] S54, testing the cores to obtain core parameters.

[0092] Preferably, the core parameters include cohesion (c), internal friction angle (ψ), density, Poisson's ratio, uniaxial compressive strength, tensile strength and compressive modulus.

[0093] Further preferably, as shown in Figure 4 , 5 and 6, in the preferred embodiment of the present application, in step S7, the seismic motion simulation technique is a direct method, which includes the following steps:

[0094] S711, when the frequencies are the same, assuming that a point is equal to a specified velocity response spectrum, and comparing the calculated acceleration response spectrum with the target spectrum;

[0095] S712, correcting and iteratively calculating other points that do not meet the requirements of fitting accuracy;

[0096] S713, completing the synthesis of acceleration when the fitting accuracy of the calculated response spectrum and the target response spectrum meets the requirements.

[0097] Of course, as shown in Figure 7 , in the preferred embodiment of the present application, in step S7, the seismic motion simulation technique is an indirect method, which includes the following steps:

[0098] S721, the power spectral density function is calculated by using the reaction spectrum;

[0099] S722, the acceleration is calculated by using the approximate relationship between the Fourier amplitude spectrum and the power spectrum;

[0100] S722, the amplitude spectrum is iteratively corrected according to the difference between the calculated reaction spectrum and the target spectrum until the calculated reaction spectrum can fit the target reaction spectrum and meet the accuracy requirement.

[0101] Further, as shown in the preferred embodiment of the present application, in step S8, the non-continuous deformation method simulation analysis comprises the following steps: Figure 8

[0102] S81, a model is established according to the spatial distribution of the active fault region and the intersection relationship with the tunnel;

[0103] S82, the unit grid is calculated;

[0104] S83, the model physical parameters are inputted; preferably, the model physical parameters include cohesion, internal friction angle, density, Poisson's ratio, uniaxial compressive strength, tensile strength, and compressive modulus.

[0105] S84, the boundary conditions and the seismic spectrum are inputted;

[0106] S85, the calculation is loaded;

[0107] S86, the calculation results are post-processed.

[0108] Further preferably, step S85 further comprises the following steps:

[0109] S851, loading blocks are added around the model, and corresponding loads are applied on the loading blocks to form extrusion stress; preferably, the load size is the product of the horizontal stress and the corresponding model side length.

[0110] S852, the loads applied on part of the loading blocks are symmetrically distributed; preferably, to ensure the balance of the load loading blocks, the loads applied on the larger load loading blocks are distributed on two symmetric points, so that the applied load is half of the product value.

[0111] S853, symmetric forced displacement points are applied on the upper load loading blocks to realize the one-way displacement of the loading blocks; preferably, the lower load loading blocks remain stationary, so that the displacement distances of the two displacement points in two directions are both set to 0, becoming fixed points. The upper load loading blocks apply displacement in the x direction, and the y direction displacement is 0, achieving the effect of one-way displacement.

[0112] ​S854, the upper load loading block cohesion is set to maximum, driving the block around the upper load loading block synchronous movement; in this step, in order to simulate the active fault zone creep, the effect of the block on both sides of the fault zone is reached, the upper load loading block will drive the contacted block to move together to x direction. Therefore, the cohesion of the upper and lower load loading blocks is set to maximum, driving the contacted block to move together.

[0113] S855, the predicted fault distance of the active fault is added to the displacement point for simulation calculation.

[0114] The near-field active fault influence evaluation method for tunnel surrounding rock in the application has wide application range, accurate survey, by adopting the comprehensive combination of traditional ground survey means, multi-source satellite remote sensing, aerial geophysical prospecting, unmanned aerial vehicle surveying and mapping and other new technologies, according to the survey process of gradually deepening from surface to point, the regional geological conditions, spatial distribution and activity characteristics of the active fault are more targeted to find out, compared with the traditional survey means, the working efficiency is improved, the terrain limitation is small, the field operation risk coefficient is reduced, the survey targeting is strengthened, and excellent economic benefits and popularization value are obtained.

[0115] Those skilled in the art will readily understand that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for evaluating the influence of a near-field active fault on tunnel surrounding rock, characterized in that, S1, collecting active fault region data, wherein the active fault region data comprises regional historical ground motion record data; S2, interpreting the active fault region by using multi-source satellite remote sensing to obtain remote sensing information, and verifying the active fault region data according to the remote sensing information to determine the region to be plotted; S3, collecting image information in the region to be plotted by using unmanned aerial vehicle oblique photography, and interpreting the plot to form a plotted geological map according to the image information; S4, collecting geophysical field data of the active fault region by using airborne geophysical prospecting and / or ground geophysical prospecting, and preparing a physical field map according to the geophysical field data; S5, determining the engineering and hydrogeological conditions and major geological feature points of the active fault region according to the active fault region data, the plotted geological map and the physical field map obtained in steps S1-S4, and performing drilling verification operations on the major geological feature points to supplement the engineering and hydrogeological conditions; S6, analyzing the active fault region data, the plotted geological map, the physical field map and the engineering and hydrogeological conditions obtained in steps S1-S5 to determine the regional geological conditions, spatial distribution and activity of the active fault region; S7, synthesizing the ground motion time history record of each seismic event in the active fault region by using ground motion simulation technology according to the regional geological conditions, spatial distribution, activity and regional historical ground motion record data; S8, constructing a tunnel and active fault region intersection model, simulating and analyzing the seismic response and damage evolution law of the tunnel surrounding rock under different action conditions by using a non-continuous deformation method, and evaluating the influence of the active fault region on the tunnel surrounding rock.

2. The method of evaluating the influence of a near-field active fault tunnel on surrounding rock according to claim 1, wherein, The active fault region data further comprises regional geological data.

3. The method of claim 1, wherein, In step S2, the multi-source satellite remote sensing is to observe the active fault region by using optical sensors, thermal infrared sensors and microwave sensors carried by satellites to obtain multi-source remote sensing image data of the active fault region.

4. The method according to any one of claims 1 to 3, wherein, Step S3 comprises the following steps: S31, collecting image information in the region to be plotted by using unmanned aerial vehicle oblique photography; S32, establishing a real scene three-dimensional model according to the image information; S33, combining the real scene three-dimensional model with remote sensing information, virtually depicting on the real scene three-dimensional model, and determining feature points to be manually plotted and verified; S34, manually plotting and verifying the feature points on site to form a plotted geological map.

5. The method according to any one of claims 1 to 3, wherein, The airborne geophysical prospecting is to obtain three-dimensional inversion results of the active fault region by using airborne transient electromagnetic method and / or airborne magnetotelluric method to determine the physical field data of the active fault region.

6. The method according to any one of claims 1 to 3, wherein The drilling verification operation comprises the following steps: S51, drilling holes at the positions of the major geological feature points; S52, actually drilling to obtain cores and related parameters thereof; S53, performing in-hole testing to obtain in-hole geological data; S54, testing the cores to obtain core parameters.

7. The method according to any one of claims 1 to 3, wherein The ground motion simulation technology is to use a direct method, comprising the following steps: S711, when the frequency is the same, assuming a point equals the specified speed response spectrum, and comparing the calculated acceleration response spectrum with the target spectrum; S712, correcting other points that do not meet the requirements of fitting accuracy and performing iterative calculation; S713, when the fitting accuracy of the calculated response spectrum and the target response spectrum meets the requirements, completing the synthesis of acceleration.

8. The method according to any one of claims 1 to 3, wherein, The seismic motion simulation technology is an indirect method, including the following steps: S721, calculating the corresponding power spectrum density function by the response spectrum; S722, obtaining the amplitude spectrum and the corresponding frequency distribution by the approximate relationship between the Fourier amplitude spectrum and the power spectrum to calculate the acceleration; S722, by calculating the difference between the response spectrum of the acceleration and the target spectrum, iteratively correcting the amplitude spectrum according to the difference between the two, so that the calculated response spectrum can fit the target response spectrum and meet the accuracy requirements.

9. The method according to any one of claims 1 to 3, wherein, In step S8, the non-continuous deformation method simulation analysis includes the following steps: S81, establishing a model according to the spatial distribution of the active fault region and the intersection relationship with the tunnel; S82, calculating the unit grid division; S83, inputting the physical parameters of the model; S84, inputting the boundary conditions and seismic spectrum; S85, loading calculation; S81, post-processing the calculation results.

10. The method of evaluating the influence of a near-field active fracture on the surrounding rock of a tunnel according to claim 9, wherein, The loading calculation includes the following steps: S851, adding loading blocks around the model and applying corresponding size loads on the loading blocks to form extrusion stress; S852, symmetrically distributing the loads applied on part of the loading blocks; S853, applying symmetric forced displacement points on the upper load loading blocks to realize one-way displacement of the loading blocks; S854, setting the cohesion of the upper load loading blocks to be maximum to drive the synchronous movement of the blocks around the upper load loading blocks; S855, adding the predicted fault distance of the active fault to the displacement point for simulation calculation.

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