A method and apparatus for geological hazard assessment based on digital numerical integration

Abstract

This invention provides a method and apparatus for geological hazard assessment based on digital-numerical integration. First, based on collected geological information data, a three-dimensional geological model and a geological information model of the assessment area are established. Then, the three-dimensional geological model is quantified to obtain a numerical model. The stress field of the assessment area is calculated using the numerical model, and then added to the geological information model to obtain a digital-numerical integrated geological information model. Finally, different geological hazards are assessed based on the digital-numerical integrated geological information model to obtain the assessment results. The geological hazard assessment method based on digital-numerical integration provided by this invention simplifies the application of three-dimensional geological model data in numerical simulation processing, combining the powerful three-dimensional geological modeling capabilities of EVS and FLAC. 3D The powerful computing capabilities of numerical simulation make the assessment of geological hazards simpler and more accurate.

Description

Technical Field

[0001] This application relates to the field of geological hazard assessment technology, specifically to a geological hazard assessment method and apparatus based on digital numerical integration. Background Technology

[0002] Sudden geological disasters during construction can cause enormous losses to human life and property. Therefore, geological hazard assessment of the construction area is of great significance for the standardization and decision-making of engineering projects. With the continuous development of geological engineering informatization, numerical simulation technology and three-dimensional geological modeling technology are being used more and more widely in the assessment of geological hazards in geotechnical engineering.

[0003] In previous technologies, three-dimensional geological models were typically constructed based on actual geological conditions. These models were used to more intuitively and accurately display the geological conditions of the site, or to simulate disaster processes using numerical simulation techniques.

[0004] Numerical simulation and 3D geological modeling are both important analytical tools for geological hazard assessment. However, currently, data from 3D geological models are difficult to apply easily in numerical simulation processes. Summary of the Invention

[0005] To overcome the problems existing in related technologies, the present invention provides a geological hazard assessment method and device based on digital numerical integration, which can overcome or partially solve the above problems.

[0006] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0007] In a first aspect, embodiments of the present invention provide a geological hazard assessment method based on integrated digital and numerical methods, characterized in that the method includes:

[0008] Based on the collected geological information data, a three-dimensional geological model and a geological information model of the assessment area are established.

[0009] The three-dimensional geological model is quantized to obtain a numerical model;

[0010] The stress field of the evaluation area is calculated using the numerical model.

[0011] The stress field is added to the geological information model to obtain a digital-numerical integrated geological information model.

[0012] The digital numerical integrated geological information model is used to assess different geological hazards and obtain assessment results.

[0013] Optionally, establishing the three-dimensional geological model and geological information model of the assessment area includes:

[0014] Based on the geological information data, a three-dimensional geological model and a geological information model of the evaluation area are established using EVS.

[0015] Optionally, the step of numerating the three-dimensional geological model to obtain a numerical model includes:

[0016] The three-dimensional geological model is exported as a DXF format file using EVS, resulting in DXF format files for the lithology model and the fault model.

[0017] Convert the DXF format file of the lithology model to a FLAC3D format file;

[0018] Import the FLAC3D format file of the lithology model and the DXF format file of the fault model into FLAC. 3D The FLAC was obtained 3D Numerical model.

[0019] Optionally, converting the DXF format file of the lithology model to a FLAC3D format file includes:

[0020] Convert the DXF format file of the lithology model to an STL format file;

[0021] The STL format file of the lithological model is split to obtain tetrahedral splitting results;

[0022] The tetrahedral subdivision result is converted into a FLAC3D format file using an interface program;

[0023] The tetrahedral subdivision results of the lithological model include the node coordinate data and node connection data of the tetrahedral elements.

[0024] Optionally, the step of partitioning the STL format file of the lithological model to obtain tetrahedral partitioning results includes:

[0025] Determine the location of the profile lines in the lithological model to obtain the profile;

[0026] The cross-section is processed into a planar straight line diagram;

[0027] The processed lithology model's STL format file is imported into MeshPy via an interface program for mesh generation, resulting in a tetrahedral mesh.

[0028] Optionally, before obtaining tetrahedral partitioning results by partitioning the STL format file of the lithological model, the method further includes:

[0029] The overlapping surface data in the lithological model were removed using the meshlab software.

[0030] Optionally, the step of converting the tetrahedral subdivision result into a FLAC3D format file via an interface program includes:

[0031] Obtain the node file and ele file that store the tetrahedral mesh generation results;

[0032] The node and ele files are output as flac3d format files.

[0033] Optionally, adding the stress field to the geological information model to obtain a digital-numerical integrated geological information model includes:

[0034] The stress field data is converted into APDV file format using an interface conversion program;

[0035] Import the stress field data in the APDV file format into EVS;

[0036] The stress field is added to the geological information model to obtain a digital numerical integrated geological information model.

[0037] Optionally, after assessing different geological hazards based on the digital numerical integrated geological information model and obtaining the assessment results, the method further includes:

[0038] The evaluation results are then visualized.

[0039] Secondly, embodiments of the present invention provide a geological hazard assessment device based on digital numerical integration, characterized in that the device comprises:

[0040] The model building module is used to build a three-dimensional geological model and a geological information model of the assessment area based on the collected geological information data.

[0041] The numericalization module is used to convert the three-dimensional geological model into a numerical model.

[0042] The stress field calculation module is used to calculate the stress field of the evaluation area through the numerical model.

[0043] An add module is used to add the stress field to the geological information model to obtain a digital-numerical integrated geological information model;

[0044] The assessment module is used to assess different geological hazards based on the digital numerical integrated geological information model and obtain assessment results.

[0045] First, based on collected geological information data, this embodiment of the invention establishes a three-dimensional geological model and a geological information model of the assessment area. Then, the three-dimensional geological model is quantified to obtain a numerical model. The stress field of the assessment area is calculated using the numerical model, and then added to the geological information model to obtain a digital-numerical integrated geological information model. This enables the application of three-dimensional geological model data in numerical simulation processing. This solution assesses different geological hazards based on the digital-numerical integrated multivariate geological information model, combining the powerful three-dimensional geological modeling capabilities of EVS and FLAC. 3D The powerful computational capabilities of numerical models can meet users' needs for analyzing complex calculation results.

[0046] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart illustrating the steps of a digital-numerical integrated geological hazard assessment method provided in an embodiment of this application.

[0049] Figure 2 This is a diagram illustrating the visualization programming and module functions for modeling tunnel water inflow information, provided in an embodiment of this application.

[0050] Figure 3 This is a schematic diagram of a surrounding rock grading model provided in an embodiment of this application;

[0051] Figure 4 This application provides a flowchart for adding a stress field to a tunnel geological information model.

[0052] Figure 5 This application provides a model for calculating the stress ratio of tunnel rockburst strength.

[0053] Figure 6 This application provides a model for calculating the strength-to-stress ratio of the surrounding rock in a tunnel with large deformation, as provided in an embodiment of this application.

[0054] Figure 7 This application provides a model for calculating the strength-to-stress ratio of the surrounding rock in a tunnel with large deformation, as provided in an embodiment of this application.

[0055] Figure 8 This is a schematic diagram of a PSLG provided in an embodiment of this application;

[0056] Figure 9 This is a schematic diagram of a three-dimensional PLC provided in an embodiment of this application;

[0057] Figure 10 This application provides an embodiment of a FLAC. 3D A schematic diagram of the default coordinate system in the diagram;

[0058] Figure 11 This is a schematic diagram of a model data conversion process provided in an embodiment of this application;

[0059] Figure 12 This is a schematic diagram of a model visualization display process provided in an embodiment of this application;

[0060] Figure 13 This is a schematic diagram illustrating a multi-layer display of a three-dimensional lithology model provided in an embodiment of this application;

[0061] Figure 14 This is a schematic diagram showing a multi-layer display of a geostress field information model provided in an embodiment of this application;

[0062] Figure 15 This is a structural block diagram of a geological hazard assessment device based on digital numerical integration provided in an embodiment of this application. Detailed Implementation

[0063] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0064] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0065] In this application embodiment, the relevant basics of geological analysis are first introduced:

[0066] EVS (Earth Volumetric Studio) is a 3D modeling and analysis software applicable to the field of Earth sciences. It can achieve true 3D modeling, analysis, and visualization of geological body data. Models created with EVS can realistically reflect geological structural morphology, tectonic relationships, and the changing patterns of internal properties within geological bodies. The models can be cut in any way to facilitate multi-angle observation and research. EVS can be used to analyze various types of geophysical data in diverse environments, meeting the needs of geology, geochemistry, environmental science, mineral exploration engineering, oceanography, and archaeology, among other fields.

[0067] FLAC 3D Fast Lagrangian Analysis of Continua 3D (FLAC) is a simulation software developed by ITASC, Inc. It is capable of simulating the stress characteristics and plastic flow analysis of three-dimensional structures in soil, rock, and other materials. 3D The actual structure is fitted by adjusting the polyhedral elements in the 3D mesh.

[0068] Cesium is an open-source library for geospatial information visualization developed in JavaScript. It was originally created by AGI (Analytical Graphics) in 2011. Cesium is based on WebGL and uses WebGL for graphics rendering. Because Cesium is a 3D virtual globe engine developed using WebGL, it has two advantages: 1. It can draw 3D graphics directly in a browser without requiring any plugins. 2. It supports operating systems such as Windows and macOS and is compatible with various browsers.

[0069] Reference Figure 1 , Figure 1 A flowchart illustrating the steps of a geological hazard assessment method based on digital numerical integration according to an embodiment of the present invention is shown. The method includes:

[0070] Step 101: Based on the collected geological information data, establish a three-dimensional geological model and a geological information model of the assessment area.

[0071] In this embodiment, the geological information data includes specific geological information data required for establishing a three-dimensional geological model and various other geological information models, such as borehole data, DEM (Digital Elevation Model) data, profile maps, geothermal data, rock mechanical parameters, hydrogeological data, surrounding rock classification data, and geostress data. These data can be obtained through exploration data and experiments.

[0072] The three-dimensional geological model is a three-dimensional quantitative stochastic model generated by integrating geological, well logging, geophysical data and various data or concepts. In essence, it is a three-dimensional grid, and each node in the grid has a series of attributes, such as porosity.

[0073] Step 102: Numericalize the three-dimensional geological model to obtain a numerical model.

[0074] In this embodiment of the application, the numerical model may be FLAC. 3D Numerical model. The three-dimensional geological model is numerically converted to obtain FLAC. 3D Numerical modeling, specifically the conversion of data format, involves transforming the data of the three-dimensional geological model established by EVS into FLAC. 3D Numerical models can compute data in various formats, and this approach can be combined with EVS's powerful 3D geological modeling capabilities and FLAC. 3D Numerical models have powerful computational capabilities.

[0075] Step 103: Calculate the stress field of the evaluation area using the numerical model.

[0076] In this embodiment, the inversion analysis method of the geostress field can be used to calculate the stress field. The inversion analysis method of the geostress field is mainly based on the stress trial-and-error method. Fixed boundary conditions or stress boundaries are set on the four sides of the model, and a fixed boundary is set on the bottom surface of the model to restrict the displacement of the model in the Z direction. Tectonic stress is applied to the model in the form of stress boundaries to simulate the tectonic stress in the region. The direction and magnitude of the set stress boundaries should conform to the regional background tectonic stress. Based on the above boundary conditions, by continuously comparing the trial calculation results with the measured results, until the calculated results at the measuring points achieve the maximum fit with the measured geostress values, the boundary conditions at this point are considered to realistically reflect the actual situation.

[0077] Step 104: Add the stress field to the geological information model to obtain a digital numerical integrated geological information model.

[0078] Adding the calculated stress field as an attribute to the multivariate geological information model achieves the purpose of adding the stress field to the multivariate geological information model. The geostress data exported and saved as APDV file format is imported into EVS, and the calculation results are combined with the geological simulation established above using the krig_3d module to obtain a digital numerical integrated multivariate geological information model, which facilitates the analysis of disasters induced by high geostress. Figure 4 This application provides a flowchart for adding a stress field to a multi-element geological information model of a tunnel, as illustrated in this embodiment. (See also...) Figure 4 Specific examples are as follows:

[0079] 1. Use the read_lines module to import tunnel axis data and unit data on the tunnel axis for disaster analysis, and use the poly_spline module to smooth the axis;

[0080] 2. Map the imported cell data onto the smoothed tunnel axis using the interp_cell_data module;

[0081] 3. Use the interp_cell_data module to map the lithological information of the lithological model onto the tunnel axis;

[0082] 4. Since the field information belongs to nodal data, the interp_data module is used to map the ground stress field information onto the tunnel axis;

[0083] 5. Finally, use the cell_to_node module to convert the cell data on the tunnel axis into node data.

[0084] Step 105: Based on the digital numerical integrated geological information model, assess different geological hazards and obtain assessment results.

[0085] Different digital numerical integrated geological information models are selected for disaster assessment based on different geological hazards. In this embodiment, the analysis of high ground stress induced hazards can be carried out by using a digital numerical integrated model of multi-dimensional geological information of the tunnel. The specific process is as follows: first, the node_computation module is used to calculate the obtained node data to obtain the disaster analysis results of each area on the tunnel axis; then, the cross_section_tubes module is used to read the calculation results in the node_computation module to realize the three-dimensional modeling of the tunnel high ground stress induced hazard analysis results.

[0086] Specifically, for rockburst hazard analysis, this embodiment can use Tao Zhenyu's criterion method, and is not limited thereto. Tao Zhenyu's criterion method is mainly based on σ... c The rockburst grade is discussed using the ratio of / σ1, where σ c σ1 represents the single-phase compressive strength of the rock, and σ1 represents the maximum principal stress of the original rock. The criteria for determining the rockburst level are as follows:

[0087]

[0088] The analysis was conducted using a digital numerical integrated model of the obtained multi-geological information of the tunnel. The strength-stress ratio on the tunnel axis was calculated using the node_computation module, and the tunnel model was established using the cross_section_tubes module. To obtain a better display effect, the tunnel diameter can be appropriately increased, and finally the rockburst intensity of each mileage section was obtained. Figure 5 This application provides a model for calculating the stress-to-strength ratio of tunnel rockburst strength in an embodiment of the present application. (Through...) Figure 5 It allows for a clear view of the likelihood of rockbursts occurring at each mileage section, enabling analysis and prediction of actual engineering projects.

[0089] For the analysis of large deformation disasters in tunnels, this application adopts the rock mechanics criterion prediction method given in the "Railway Tunnel Design Code" (TB10003-2016) for classifying large deformations in soft rock. Table 1 is the classification table for large deformations in soft rock given in the "Railway Tunnel Design Code" (TB 10003-2016):

[0090] Table 1. Classification of Large Deformations (《Code for Design of Railway Tunnels》(TB 10003-2016))

[0091]

[0092] As shown in Table 1, the degree of large deformation mainly depends on the surrounding rock strength Rb and the maximum principal stress σmax, but the surrounding rock strength is not the same as the rock strength. The strength of the surrounding rock is mainly affected by two factors: rock strength and geological structure. In this embodiment, the parameters of the influence of geological structure on the surrounding rock strength given by Jia Xuebin (2016) can be used. By converting the uniaxial saturated compressive strength of the rock in the region according to the location of the corresponding geological structure, the strength Rb of the surrounding rock in that region can be obtained. Table 2 shows the degree of influence of geological structure on rock mass strength given by Jia Xuebin:

[0093] Table 2. Influence of Geological Structures on Rock Mass Strength (Jia Xuebin, 2016)

[0094]

[0095]

[0096] Based on statistical analysis of soft rock test data in the tunnel area, assuming the compressive strength RC of the main soft rock strata in the tunnel area is taken as 20 MPa, the conversion coefficient of the uniaxial saturated compressive strength of the rock in each section of the tunnel is imported into the software as unit data using ELF files. To make the obtained analysis results more accurate, the cell_to_node module is used to convert the unit data into node data; then the node_computation module is used to calculate the ratio of surrounding rock strength stress in different areas of the tunnel, and the resulting calculation model is obtained.

[0097] Figure 6 This is a model for calculating the strength-to-stress ratio of the surrounding rock under large deformation in the left tunnel. Figure 7 This model calculates the strength-stress ratio of the surrounding rock for large deformation in the right tunnel. In this model, metamorphic sandstone strata are not analyzed for large deformation. The fault regions traversed by the tunnel require separate calculation of node data. According to the attached table, the conversion factor for the fault regions is taken as 0.33, and the maximum principal stress value in the fault regions is approximately 15 MPa. The calculated strength-stress ratio of the surrounding rock in the fault regions is approximately 0.44. Therefore, Class I large deformation may occur in the fault regions traversed by both the left and right tunnels. This method is used to analyze and predict the large deformation of the surrounding rock at each mileage section of the tunnel.

[0098] In this embodiment of the application, the three-dimensional geological model includes a lithology model and a fault model without faults; the multi-element geological information model includes at least one geological information model.

[0099] Optionally, step 101 includes:

[0100] Based on the geological information data, a three-dimensional geological model and a geological information model of the evaluation area are established using EVS.

[0101] The establishment of a 3D geological model of the assessment area using EVS can be achieved by using indicator kriging based on borehole data and DEM data. The borehole data package contains borehole numbers, X and Y coordinates of borehole points, depth or elevation of each lithological interface within the borehole, and the lithology of the corresponding segment. The DEM (Digital Elevation Model) data is a digital representation of the terrain surface morphology. DEM data can be obtained using domestic GIS (Geographic Information System) software.

[0102] Table 3 is an example of a borehole data file format provided in this application embodiment. The top and bottom lithological surface elevations can also be replaced with the depths of lithological interfaces. If replaced with the depths of lithological interfaces, an additional column for borehole opening elevation data is required. After the borehole data is compiled, it needs to be converted into a PGF file using EVS. Based on the converted PGF file, the stratigraphic sequence in the borehole is divided using the make_geo_hierarchy module to obtain a GMF file. The obtained GMF file is then imported into the krig_3d_geology module for formation modeling. If borehole data is needed to build a lithological model, the PGF file can be used directly for modeling.

[0103] The PGF, GMF, and APDV file formats are the primary ASCII input file formats in EVS. A PGF file is a set of data files, where each section represents the lithology of a single borehole; typical borehole columnar sections can be easily converted to PGF format. A GMF file format represents a series of geological horizons used to define geological layers; each horizon can contain any number of XYZ coordinates, but interpolation is still required to handle interlayers and dipping strata. The "make_geo_hierarchy" module can generate GMF files from PGF files. The APDV (Analysis Point Data Value) format is suitable for all analytical data measured at a single point. Even data detected within very small intervals should generally be represented as a single-point (XYZ coordinate) detection at the midpoint of that interval. This format should be used for the time-domain data of a single analyte.

[0104] Table 3 Examples of borehole data file formats

[0105]

[0106] The specific process of establishing a three-dimensional geological model mainly includes the following steps:

[0107] 1. First, enter the borehole data into an Excel file, and then convert the imported EVS borehole data Excel table into a GMF file to build the model surface;

[0108] 2. Define the interpolation range based on the DEM data and select an appropriate elevation as the base of the model;

[0109] 3. Set the mesh type in the krig_3d_geology module to the Finite Difference option, and set the mesh parameters reasonably according to the actual situation of the model to divide the three-dimensional mesh;

[0110] 4. Transfer the data from krig_3d_geology to the indicator_geology module, and select the indicator kriging method for lithological modeling. When modeling, set the Lithology Method option to smooth to obtain a lithological model with smooth stratigraphic interfaces.

[0111] 5. For fault modeling, it is first necessary to find the spatial relationship between the fault and the tunnel axis, use the draw_lines module to draw the position of the fault line, and then use the extrude module to extrude the fault according to the position of the fault line and set the dip angle of the fault to obtain the fault plane.

[0112] 6. After establishing the fault plane, use the surf_cut module to cut the model using the fault plane, and finally use the intersection_shell module to screen the fault plane according to its thickness to obtain the fault model.

[0113] The appropriate altitude refers to the altitude selected as the bottom surface of the model, which can encompass the entire modeling area. For example, when building a tunnel model, the selected altitude as the bottom surface of the model should be able to encompass the entire tunnel.

[0114] The indicated kriging method is a non-parametric geostatistical method. For the lithology of a point in space, an indicated transformation is required according to the following formula: where I(x, Z) i The value is the indicator transformation obtained based on the lithology observed at point x.

[0115]

[0116] If a series of different lithologies Z are given i Then the lithology estimate at a certain point x0 is I*(x0, Z). i The calculation method for ) is as follows:

[0117]

[0118] The variation function of the indicator Kriging is:

[0119]

[0120] The experimental variation function of the indicator Kriging is:

[0121]

[0122] After fitting the variance function, the theoretical indicator variance function is obtained. Following the acquisition of the theoretical indicator variance function, the conditions of unbiased estimation and minimum variance must be met, resulting in the indicator kriging equations:

[0123]

[0124] Where μ is a Lagrange multiplier; γ(x α x β Z i ) is x α With x β The indicative variogram values ​​between; γ(x) α , x0; Z i () represents the point to be estimated x0 and the sampling point x. α The value of the indicator variation function between them; after solving the above system of equations, λ can be obtained. α (Z i Then, by following the calculation method for lithology estimation, the probability of a certain lithology appearing at the point to be estimated can be obtained.

[0125] The establishment of a multi-dimensional geological information model of the assessment area using EVS can include models for tunnel water inflow, surrounding rock classification, high ground temperature, and geostress. In this embodiment, the tunnel water inflow can be calculated using a suitable formula for each mileage segment of the left and right tunnels. Surrounding rock classification data can be obtained from the survey report of the target tunnel, and this data can be rewritten into an ELF file format to prepare for subsequent modeling. High ground temperature data can generally be obtained from the survey report, yielding a fitting equation for the temperature-depth curve, or a fitting equation based on the measured ground temperature gradient, surface temperature, and depth. The rock mechanics parameters in the calculation model can be set by comprehensively considering survey data, experimental simulations, and empirical data. The following is an example of the process for establishing models for tunnel water inflow, surrounding rock classification, and high ground temperature:

[0126] (I) Example of the process of establishing a water inflow information model:

[0127] The "Specifications for Hydrogeological Investigation of Railway Engineering" (TB10049-2016) and the "Handbook of Railway Engineering Geology" (1999 revised edition) provide formulas for calculating water inflow using different methods. The formula for the precipitation infiltration method is as follows:

[0128] Q = 2.74·α·W·A

[0129] In the formula, α is the precipitation infiltration coefficient; W is the annual precipitation in mm; and A is the catchment area of ​​the aquifer through which the tunnel passes in km². 2 Besides the precipitation infiltration method, there are other methods such as the groundwater runoff modulus method and the groundwater dynamic method to calculate tunnel water inflow. One can choose one of these methods to calculate the water inflow, or multiple methods can be used to calculate the water inflow and the average value of the water inflow can be taken as the water inflow. This application does not impose any restrictions on this.

[0130] First, the water inflow is calculated using the formula. The calculated water inflow, along with data such as the route, starting mileage, and ending mileage, is then written into an Excel spreadsheet and rewritten as an ELF file (Executable and Linking Format). The ELF file format is used for binary files, executable files, object code, shared libraries, and kernel dumps. Figure 2 A diagram illustrating the visualization programming and module functions for tunnel water inflow information modeling provided in this application is shown below. Figure 2 The `read_lines` module is used to read the ELF files containing water inflow data for the left and right tunnel lines respectively. This information is then passed to the `tubes` module to obtain the tunnel water inflow information model. Table 4 shows an example of a normal water inflow data file format for the left and right tunnel lines provided in this application embodiment.

[0131] Table 4. Normal water inflow data file format for the left and right tunnels.

[0132]

[0133] The ELF file format, used to store line segment data, contains the X, Y, and Z coordinates of the line segment nodes. This file describes the position of the line segment nodes in three-dimensional space and the attribute values ​​at that point. ELF files must be saved in ASCII format, with data separated by commas, spaces, and tabs. The file extension must be .elf for the file to be recognized by software. Different parts of an ELF file are primarily separated by file tags. An example of an ELF file tag is shown below:

[0134] COORD_UNITS“m”

[0135] Define the units of coordinates in the file.

[0136] NUM_DATA 7 1

[0137] This indicates the number of node data items and the number of cell data items contained in the file. "7" means that the file contains two node data items, and "1" means that the file contains one cell data item.

[0138] NODE_DATA_DEF 0 "TOTHC" "log_ppm"

[0139] Define the name and unit of the node data. The first value "0" is the sequence number of the node data, and the second value...

[0140] "TOTHC" defines the name of the node data, and the third value "log_ppm" defines the unit of the node data.

[0141] CELL_DATA_DEF 0 "Indicator" "Discreet Unit"

[0142] Define the cell data; the definitions of related values ​​are the same as above.

[0143] LINE 5

[0144] At the beginning of the line segment, "5" indicates that the unit data of this line is 5.

[0145] CLOSED

[0146] It needs to be written at the end of the line segment, defining the line segment as a closed segment when the first and last points are connected.

[0147] END

[0148] Placed at the end of the document, it indicates the end of the document.

[0149] Table 5 is an example of an ELF file format provided in the embodiments of this application.

[0150] Table 5 Examples of ELF file formats

[0151]

[0152] (II) Example of the process of establishing a surrounding rock classification information model:

[0153] First, the obtained surrounding rock classification data is rewritten into ELF file format, with the surrounding rock grade of each segment written into the ELF file as unit data. The obtained surrounding rock classification data ELF files for the left and right tunnels are imported into the software using the read_lines module, and then the tubes module is used to model the tunnel, resulting in the tunnel surrounding rock classification information model. Figure 3 This is a schematic diagram of a surrounding rock grading model provided in an embodiment of this application. See also... Figure 3 As can be seen, different grades of surrounding rock sections can be represented by different colors. For example, Grade V surrounding rock sections are represented by red, Grade IV surrounding rock sections by yellow, and Grade III surrounding rock sections by blue.

[0154] (III) Example of the process of establishing a high ground temperature information model for tunnels:

[0155] In this embodiment, the fitting equation for the temperature-depth curve can be obtained based on the field ground temperature test results. After obtaining the temperature-depth fitting equation, the tunnel temperature field is analyzed using the burial depth node data in the geological model established by EVS. The grid accuracy in the Z direction of the model is set to 40, and the bottom elevation of the model is set to 2700m (selected according to the actual situation of the model). The node_computation module is used to calculate the tunnel temperature field based on the burial depth node data, and the final high ground temperature information model of the tunnel is obtained.

[0156] The fitting equation for the temperature-depth curve, obtained from the on-site ground temperature test results, is as follows:

[0157] y = 0.0214x + 2.576

[0158] In the formula, x represents depth and y represents ground temperature; by engineering analogy, the ground temperature gradient is 2.14℃ / 100m.

[0159] Optionally, step 102 includes:

[0160] Sub-step 1021: Export the three-dimensional geological model as a dxf format file using EVS to obtain dxf format files for the lithology model and the fault model.

[0161] The DXF format file is an AutoCAD (Drawing Interchange Format) drawing exchange file, a file format developed by Autodesk for data exchange between AutoCAD and other software. DXF is an open vector data format, which can be divided into ASCII and binary formats, and is widely used, becoming a standard in practice. The three-dimensional geological model includes a lithological model and a fault model.

[0162] Sub-step 1022: Convert the dxf format file of the lithology model into a flac3d format file.

[0163] Sub-step 1023: Import the FLAC3D format file of the lithology model and the DXF format file of the fault model into FLAC. 3D The FLAC was obtained 3D Numerical model.

[0164] Optionally, sub-step 1022 includes:

[0165] Sub-step 10221: Convert the DXF format file of the lithology model into an STL format file.

[0166] The STL (Stage Lithography) file format was created by 3D Systems and originally used for stereolithography computer-aided design software. STL files describe the surface geometry of a 3D object, but not its color, texture maps, or other common 3D model attributes. STL formats exist in both text and binary formats. An STL file consists of definitions for multiple triangle faces, each including the 3D coordinates of its vertices and the face's normal vector.

[0167] Sub-step 10222: The STL format file of the lithology model is split to obtain tetrahedral splitting results.

[0168] The processed results are output using the save_evs_field module, along with their vertex, line segment, and attribute data, and then imported into the Triangle to ultimately achieve mesh generation for arbitrary cross-sections.

[0169] Sub-step 10223: Convert the tetrahedral subdivision result into a FLAC3D format file through the interface program.

[0170] The tetrahedral subdivision results of the lithological model include the node coordinate data and node connection data of the tetrahedral elements.

[0171] Optionally, sub-step 10222 includes:

[0172] Sub-step 111: Determine the position of the profile line in the lithological model to obtain the profile.

[0173] In this embodiment of the application, the thin_fence module of EVS is used to extract arbitrary cross sections in the model. The position of the section line that needs to be cut in the established model is determined, thereby obtaining the required cross section of the model.

[0174] Sub-step 112: Process the cross-section into a planar straight line diagram.

[0175] The planar straight line graph format, i.e., the PSLG format, requires the meshpy.triangle module in Python to perform meshing of arbitrary cross-sections of the stratigraphic model. Therefore, the meshed region needs to be represented in the form of PSLG. After obtaining the cross-section, the cross-section is processed to meet the definition of PSLG.

[0176] Figure 8This is a schematic diagram of a PSLG provided in an embodiment of this application. A PSLG is a collection of vertices and line segments. The region boundary of a PSLG is composed of line segments, and the endpoints of these line segments are vertices in the PSLG. The shape with the smallest area among all closed shapes containing hole points is set as a hole. In the figure, "4" is composed of vertices and line segments composed of vertices. When the region to be subdivided contains holes, the coordinates of the hole points (the coordinates of point A in the figure) need to be input.

[0177] Sub-step 113: Import the processed lithology model's STL format file into MeshPy via the interface program for mesh generation, obtaining tetrahedral meshing results.

[0178] MeshPy is a constraint triangulation module for Python that can improve the generation of high-quality triangles and tetrahedral meshes, and is mainly used in various finite element simulations.

[0179] Optionally, before sub-step 10222, the method further includes:

[0180] Sub-step 10224: Remove overlapping surface data from the lithological model using MeshLab software.

[0181] The MeshLab software (3D geometry processing system) is an open-source, scalable system for processing and editing unstructured 3D triangular meshes. It aims to provide a complete set of tools for scanning, editing, cleaning, merging, inspecting, presenting, and transforming mesh data.

[0182] In this embodiment, directly meshing the model generated by the standard stratigraphic model building module in EVS will result in meshing failure. The inventors discovered through analysis that this is because the generated stratigraphic model has overlapping layers; that is, each stratigraphic layer in the model contains data for both its top surface and the bottom surface of the overlying stratigraphic layer. These two surfaces are actually the same layer. This problem clearly means that the derived model does not meet the definition of a 3D PLC (piecewise linear complex). To achieve tetrahedral meshing of the stratigraphic model, it is necessary to analyze the data structure of the stratigraphic model to ensure that the data structure meets the requirements of a 3D PLC.

[0183] MeshLab software is used to remove overlapping surface data to ensure the model meets the definition of a 3D PLC. The 3D model to be meshed needs to be expressed in the form of a 3D PLC. For a 3D PLC set composed of elements, it must meet the following two requirements: the boundary of each element in the set is the union of some elements in the set; if two different elements in the set intersect, the intersection of these two elements is the union of some elements in the set. A 3D PLC can flexibly describe the 3D features of geometry. For example, it allows patches, line segments, and vertices to be at arbitrary positions in space, allowing users to constrain the meshing results based on boundary conditions. The specific implementation method of a 3D PLC is to discretize the surface of the 3D PLC to be meshed into a set composed of nodes and triangular meshes. First, the generated model needs to be exported to DXF file format using the write_cad module, then the model format is converted to STL file format, and finally, overlapping surface data is removed using MeshLab software.

[0184] Figure 9 This is a schematic diagram of a three-dimensional PLC provided in an embodiment of this application. As can be seen from the figure, the PLC does not allow the units thereto to intersect. For example, two facets can only intersect on a set of vertices or line segments belonging to a set.

[0185] Optionally, sub-step 10223 includes:

[0186] Sub-step 121: Obtain the node file and ele file that store the tetrahedral mesh generation results.

[0187] The node file mainly stores the node data in the tetrahedral mesh generation results, while the ele file mainly stores the tetrahedral mesh data.

[0188] Sub-step 122: Output the node file and ele file as a flac3d format file.

[0189] In this embodiment, the TET_FLAC function, using Python, reads the node and ele files (containing tetrahedral mesh generation results) obtained from MeshPy.tet, converts the data, and outputs a FLAC3D format mesh file. The node file mainly stores the node data of the tetrahedral mesh, and the ele file mainly stores the tetrahedral mesh data. By reading and converting the data from the node and ele files using Python, the computational model obtained from the mesh generation can be imported into FLAC. 3D Calculated in the middle.

[0190] In addition, in this embodiment, outputting the node file and ele file as a flac3d format file may specifically include: changing the prefix of the node coordinate data in the tetrahedral partitioning result to a first form, changing the prefix of the node connection data in the tetrahedral partitioning result to a second form, and changing the identifier of the unit in each group under the first label. The first and second forms are formats that conform to the flac3d file format requirements. When writing data to flac3d, the format is changed before writing to FLAC. 3D When writing node coordinate data to FLAC3D, the node coordinate data in the FLAC3D file needs to be prefixed with "G node ID"; while when writing to FLAC3D... 3D When writing element data, the node connection data of tetrahedral elements needs to be prefixed with "ZT4". Therefore, the prefixes of the node coordinate data and node connection data in the tetrahedral meshing results need to be modified. The first tag is the *GROUPS tag. After modifying the node data and element data, the identifiers of the elements in each material group are written under the *GROUPS tag to complete the conversion between the two model file formats.

[0191] It should be added that before exporting the node and ele files as FLAC3D format files, the tetrahedral elements of the lithology model need to be converted to FLAC format. 3D The arrangement follows the right-hand rule. The "right-hand rule" refers to the coordinate system's right-hand rule, which states that regardless of how the coordinates are chosen in space, they always have a certain orientation. Figure 10 It's FLAC 3D A schematic diagram of the default coordinate system in the diagram.

[0192] Tetrahedral elements of lithological models and FLAC 3D The definition of the tetrahedral mesh is the same, but because FLAC 3D The node arrangement order of tetrahedral elements in the model must satisfy the "right-hand rule". However, the node arrangement order of tetrahedral elements in the lithological model is not arranged according to the "right-hand rule". Therefore, it is necessary to obtain the correspondence between the nodes of the two types of tetrahedral elements in order to complete the data conversion between the models. Figure 11 This is a schematic diagram of a model data conversion process provided in an embodiment of this application, which converts the node arrangement order of tetrahedral elements in a lithological model into a FLAC-compliant format. 3D The node arrangement order of the "right-hand rule".

[0193] Optionally, step 104 includes:

[0194] Sub-step 1041: Convert the stress field data into APDV file format using an interface conversion program.

[0195] The APDV file format is a file format in EVS. The analysis point data value (.apdv) format is applicable to all analysis data measured at a certain point.

[0196] Sub-step 1042: Import the stress field data in the APDV file format into EVS.

[0197] Since the post-processing of the obtained numerical model requires importing the calculation results of FLAC3D into EVS, the APDV file input format provided by EVS is used as the data interface. The file mainly stores the X, Y, and Z coordinate data of points in space, as well as the values ​​of different attributes at each point. The file format is simple, and the data obtained from numerical simulation can be imported into the software by writing a data interface program.

[0198] Sub-step 1043: Add the stress field to the geological information model to obtain a digital numerical integrated geological information model.

[0199] Optionally, after step 105, the method further includes:

[0200] Step 106: Visualize the evaluation results.

[0201] This application selects the Cesium platform as the display platform for multivariate geological information models, and no limitation is made here. Figure 12 This is a schematic diagram of a model visualization display process provided in an embodiment of this application. See also... Figure 12 First, the model needs to be output in DXF / DWG format using the software's write_cad module. The output model is a boundary representation model composed of triangular meshes. Then, 3DS MAX software is used to convert the DXF / DWG format to DAE (Digital Asset Exchange, 3D interactive file format) file format. Finally, the model is displayed on the web using the DAE file format. The DAE file format is generally used for exchanging digital data between multiple graphics programs.

[0202] Cesium Lab's 3D model attribute import function allows users to assign attributes to different parts of a model created in EVS and generate 3D Tiles model files. These files can then be uploaded to the platform for display across different layers, which users can access via a web interface. Furthermore, users can click on different parts of the model to highlight them and display corresponding information. This feature displays text and images of the selected part's attributes in a pop-up window on the right side of the website interface.

[0203] Figure 13This is a schematic diagram illustrating a multi-layer display of a three-dimensional lithology model provided in an embodiment of this application. Figure 13 This paper presents the effect of jointly displaying a 3D geological model uploaded to the Cesium platform with the platform's provided 3D surface imagery data. In this embodiment, the model's position can be set below the ground surface during upload, resulting in a high degree of alignment between the model's upper surface and the ground surface. By adjusting the surface transparency, the combined display effect of the 3D geological model and 3D surface imagery data is improved. Figure 13 The window on the right shows the effect of displaying detailed information about a stratum by clicking on it with the mouse. Users can add different information to the model as needed to achieve a 3D display of the model on the web and the display of corresponding text and chart data.

[0204] Figure 14 This is a schematic diagram showing a multi-layer display of a geostress field information model provided in an embodiment of this application.

[0205] In summary, the geological hazard assessment method based on digital-numerical integration provided in this application includes first establishing a three-dimensional geological model and a multivariate geological information model of the assessment area using EVS, and then numerically converting the three-dimensional geological model to obtain FLAC. 3D Numerical model and through the FLAC 3D The stress field of the assessment area is calculated using a numerical model. By adding this stress field to the multivariate geological information model, a digital-numerical integrated multivariate geological information model is obtained, enabling the application of 3D geological model data in the post-processing of numerical simulation. This scheme assesses different geological hazards based on the digital-numerical integrated multivariate geological information model, combining EVS's powerful 3D geological modeling capabilities with FLAC. 3D The powerful computational capabilities of numerical models can meet users' needs for analyzing complex calculation results. Furthermore, after obtaining the evaluation results, the established model and the analysis and evaluation results can be visualized across platforms, making it convenient for users to view and analyze them.

[0206] The assessment method provided in this application embodiment can be implemented by a geological disaster assessment device based on digital numerical integration.

[0207] Reference Figure 15 , Figure 15 This is a structural block diagram of a geological hazard assessment device based on digital numerical integration, as provided in an embodiment of this application. Figure 15 As shown, the evaluation device includes:

[0208] The model building module 201 is used to build a three-dimensional geological model and a geological information model of the assessment area based on the collected geological information data.

[0209] The numericalization module 202 is used to numerically convert the three-dimensional geological model into a numerical model.

[0210] The stress field calculation module 203 is used to calculate the stress field of the evaluation area through the numerical model.

[0211] Add module 204 to add the stress field to the geological information model to obtain a digital numerical integrated geological information model.

[0212] The evaluation module 205 is used to evaluate different geological hazards based on the digital numerical integrated geological information model and obtain evaluation results.

[0213] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. Those skilled in the art, under the guidance of this application, can make many modifications without departing from the spirit and scope of the claims, all of which are within the protection of this application.

[0214] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, apparatus, or computer program products. Therefore, embodiments of the present invention can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of the present invention can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0215] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0216] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0217] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0218] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0219] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0220] The above provides a detailed description of the geological hazard assessment method and apparatus based on digital numerical integration provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A geological hazard assessment method based on digital-numerical integration, characterized in that, The method includes: Based on the collected geological information data, a three-dimensional geological model and a geological information model of the assessment area are established. The three-dimensional geological model is quantized to obtain a numerical model; The stress field of the evaluation area is calculated using the numerical model. The stress field is added to the geological information model to obtain a digital-numerical integrated geological information model. The digital numerical integrated geological information model is used to assess different geological hazards, and the assessment results are obtained. The process of numerating the three-dimensional geological model to obtain a numerical model includes: The three-dimensional geological model is exported as a DXF format file using EVS, resulting in DXF format files for the lithology model and the fault model. Convert the DXF format file of the lithology model to a FLAC3D format file; Import the FLAC3D format file of the lithology model and the DXF format file of the fault model into FLAC. 3D The FLAC was obtained 3D Numerical model; The step of adding the stress field to the geological information model to obtain a digital-numerical integrated geological information model includes: The stress field data is converted into APDV file format using an interface conversion program; Import the stress field data in the APDV file format into EVS; The stress field is added to the geological information model to obtain a digital numerical integrated geological information model.

2. The method according to claim 1, characterized in that, The establishment of the three-dimensional geological model and geological information model of the assessment area includes: Based on the geological information data, a three-dimensional geological model and a geological information model of the evaluation area are established using EVS.

3. The method according to claim 1, characterized in that, The step of converting the DXF format file of the lithology model into a FLAC3D format file includes: Convert the DXF format file of the lithology model to an STL format file; The STL format file of the lithological model is split to obtain tetrahedral splitting results; The tetrahedral subdivision result is converted into a FLAC3D format file using an interface program; The tetrahedral subdivision results of the lithological model include the node coordinate data and node connection data of the tetrahedral elements.

4. The method according to claim 3, characterized in that, The process of partitioning the STL format file of the lithological model to obtain tetrahedral partitioning results includes: Determine the location of the profile lines in the lithological model to obtain the profile; The cross-section is processed into a planar straight line diagram; The processed lithology model's STL format file is imported into MeshPy via an interface program for mesh generation, resulting in a tetrahedral mesh.

5. The method according to claim 3, characterized in that, Before obtaining tetrahedral partitioning results by partitioning the STL format file of the lithological model, the method further includes: The overlapping surface data in the lithological model were removed using the meshlab software.

6. The method according to claim 3, characterized in that, The step of converting the tetrahedral subdivision result into a FLAC3D format file via an interface program includes: Obtain the node file and ele file that store the tetrahedral mesh generation results; The node and ele files are output as flac3d format files.

7. The method according to claim 1, characterized in that, After assessing different geological hazards based on the digital numerical integrated geological information model and obtaining the assessment results, the process further includes: The evaluation results are then visualized.

8. A geological hazard assessment device based on digital numerical integration, characterized in that, The device includes: The model building module is used to build a three-dimensional geological model and a geological information model of the assessment area based on the collected geological information data. The numericalization module is used to convert the three-dimensional geological model into a numerical model. The stress field calculation module is used to calculate the stress field of the evaluation area through the numerical model. An add module is used to add the stress field to the geological information model to obtain a digital-numerical integrated geological information model; The assessment module is used to assess different geological hazards based on the digital numerical integrated geological information model and obtain assessment results; The numericalization module is specifically used for: The three-dimensional geological model is exported as a DXF format file using EVS, resulting in DXF format files for the lithology model and the fault model. Convert the DXF format file of the lithology model to a FLAC3D format file; Import the FLAC3D format file of the lithology model and the DXF format file of the fault model into FLAC. 3D The FLAC was obtained 3D Numerical model; The added module is specifically used for: The stress field data is converted into APDV file format using an interface conversion program; Import the stress field data in the APDV file format into EVS; The stress field is added to the geological information model to obtain a digital numerical integrated geological information model.

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