CN-121999161-A - Method and system for predicting extrusion type large deformation of inter-layer stratum of composite lithology

CN121999161ACN 121999161 ACN121999161 ACN 121999161ACN-121999161-A

Abstract

The invention discloses a method and a system for predicting extrusion type large deformation of a composite lithology interlayer stratum, which belong to the field, wherein the method comprises the steps of acquiring basic geology and lithology data; the method comprises the steps of constructing a three-dimensional geological model by utilizing processed basic geology and lithology data, carrying out grid division on the three-dimensional geological model based on a preset division rule, carrying out inversion on stress values of grids based on a twice inversion mechanism to obtain accurate stress field cloud images, carrying out viscoelastic-plastic partitioning on the accurate stress field cloud images based on an expansion capacity effect to determine the type of each partition to which each grid belongs, carrying out excavation simulation on the three-dimensional geological model, solving the strain component and displacement of each partition to which each grid belongs based on the expansion capacity effect model, constructing a related data set according to the strain component, the displacement and the basic geology and lithology data, and inputting the related data set into an extrusion type large-deformation prediction model to obtain a deformation prediction result. The invention has higher prediction precision and generalization capability.

Inventors

LI DIANDIAN
ZHOU YONGHONG
CHEN LEI
QU YINGHONG
CHEN CAN
TIAN ZHILI

Assignees

四川川交路桥有限责任公司

Dates

Publication Date: 20260508
Application Date: 20260127

Claims (10)

1. The method for predicting the extrusion type large deformation of the inter-layer stratum of the composite lithology is characterized by comprising the following steps of: Acquiring basic geology and lithology data of a target area, preprocessing and integrating the basic geology and lithology data, and obtaining processed basic geology and lithology data; Constructing a three-dimensional geological model of the target area by using the processed basic geology and lithology data, and carrying out grid division on the three-dimensional geological model based on a preset division rule to obtain a grid cell system; inverting stress values of grids of the grid cell system based on a preset twice inversion mechanism to obtain an accurate ground stress field cloud picture of the target area; Performing viscoelastic-plastic partitioning on an accurate stress field cloud image of a target area based on an expansion effect, and determining the type of a partition to which each grid in a grid unit system belongs; performing excavation simulation on the three-dimensional geological model based on numerical simulation, and solving the strain components and displacement of the subareas of the residual grids after the excavation simulation based on the expansion effect model; and constructing a related data set according to the strain component and the displacement of each grid belonging to the partition and the corresponding processed basic geology and lithology data, and inputting the related data set into a pre-constructed extrusion type large-deformation prediction model to obtain a deformation prediction result.
2. The method for predicting the extrusion type large deformation of the inter-layer stratum of the composite lithology according to claim 1, wherein the basic geology and lithology data comprise stratum structure data, lithology mechanical data, bedding distribution data and ground stress data; The stratum structure data comprises lithology combination type, single lithology single layer thickness and alternating frequency of an interlayer section, main lithology thickness, interlayer lithology type, interlayer thickness and extension length of the interlayer section; The lithologic mechanical data comprises elastic modulus, internal friction jiao, density, cohesive force and poisson ratio of a interlayer section; the bedding distribution data comprises the relative position, the tendency, the spacing and the internal friction jiao of the bedding and the tunnel; The ground stress data comprise a viscosity coefficient, an expansion coefficient, a humidity change maximum value, a permeability coefficient and a dilatation coefficient.
3. The method for predicting the extrusion type large deformation of the inter-layer stratum of the composite lithology according to claim 2, wherein the twice inversion mechanism is as follows: extracting basic geology and lithology data of each grid, and constructing feature vectors according to the basic geology and lithology data of each grid; inputting the feature vector into a pre-constructed primary inversion model for stress solving to obtain an initial ground stress field cloud picture; And constructing a numerical model of the target area, performing secondary inversion on the initial ground stress field cloud image according to the numerical model to obtain a ground stress field cloud image subjected to secondary inversion, and taking the ground stress field cloud image subjected to secondary inversion as an accurate ground stress field cloud image.
4. The method for predicting the extrusion type large deformation of the inter-layer stratum of the composite lithology according to claim 3, wherein constructing a numerical model of a target area, performing secondary inversion on an initial ground stress field cloud picture according to the numerical model to obtain a ground stress field cloud picture after the secondary inversion comprises the following steps: stress monitoring values of a plurality of monitoring points of the target area are obtained; Based on a numerical simulation algorithm, constructing an initial numerical model by taking an initial ground stress field cloud picture as a boundary load and taking lithologic mechanical data and ground stress data as input parameters; Operating an initial numerical model, determining stress simulation values of grids, and extracting stress simulation values of grids corresponding to a plurality of monitoring points; determining stress relative errors of all monitoring points according to the stress monitoring values and the stress simulation values of all the monitoring points; Judging whether the stress relative errors of all the monitoring points are smaller than a preset threshold value, if not, correcting the boundary load and the input parameters based on a preset correction rule, and recalculating the relative errors of all the monitoring points until the stress relative errors of all the monitoring points are smaller than the preset threshold value, so as to reconstruct a numerical model by the corrected boundary load and lithologic data, and obtaining a final numerical model; And determining final stress data of each grid according to the final numerical model, and generating a final ground stress field cloud picture according to the final stress data of each grid, wherein the final ground stress field cloud picture is used as a ground stress field cloud picture after secondary inversion.
5. The method for predicting the extrusion type large deformation of the interbedded strata of the composite lithology according to claim 4, wherein the preset correction rule comprises: Adopting a control variable method and increasing or decreasing input parameters by a preset adjustment step length; And (5) adjusting the boundary load distribution form and refining the stress concentration area grid.
6. The method for predicting the extrusion type large deformation of the inter-layer stratum of the composite lithology according to claim 2, wherein the types of the subareas comprise a viscoelastic area, a viscoplastic area and a viscoplastic residual area, and the expansion effect model comprises a viscoelasticity model constructed on the basis of a Kelvin model, a viscoplastic model constructed on the basis of a double-shear stress yield model and a residual model constructed on the basis of a Centipeda model.
7. The method for predicting the extrusion type large deformation of the inter-layer stratum of the composite lithology according to claim 1, wherein the method for solving the strain component and the displacement of the subarea of each remaining grid after excavation simulation based on the expansion capacity effect model comprises the following steps: obtaining the thickness of each grid; When the type of the partition is a viscoelastic region, calling a viscoelastic model, taking stress data, elastic modulus, viscosity coefficient and expansion coefficient corresponding to each grid as input of the viscoelastic model to obtain total strain, and determining viscoelastic displacement according to the total strain and thickness; When the type of the partition is a plastic region, a plastic model is called, the internal friction jiao and the expansion coefficient corresponding to each grid are used as the input of the plastic model, a plastic strain component is determined, and the plastic displacement is determined according to the plastic strain component and the thickness; When the type of the partition is a viscoplastic residual region, a residual model is called, the expansion coefficient, the elastic modulus and the viscosity coefficient corresponding to each grid are used as input of the residual model, the total residual strain is determined, the initial displacement is determined according to the total residual strain and the thickness, the additional displacement is determined according to the expansion coefficient and the viscosity coefficient, and the residual displacement is determined according to the initial displacement and the additional displacement.
8. A system for predicting a large deformation of a composite lithology in a manner of extrusion of a interbedded strata, for implementing the method for predicting a large deformation of a composite lithology in a manner of extrusion of a composite lithology in a interbedded strata according to any one of claims 1 to 7, said system comprising: The data acquisition module is used for acquiring basic geology and lithology data of the target area, preprocessing and integrating the basic geology and lithology data, and obtaining processed basic geology and lithology data; The grid construction module is used for constructing a three-dimensional geological model of the target area by utilizing the processed basic geology and lithology data, and carrying out grid division on the three-dimensional geological model based on a preset division rule to obtain a grid cell system; the stress inversion module is used for inverting the stress value of each grid of the grid cell system based on a preset twice inversion mechanism to obtain an accurate stress field cloud image of the target area; The grid partition module is used for carrying out viscoelastic-plastic partition on the accurate stress field cloud image of the target area based on the expansion capacity expansion effect and determining the type of partition to which each grid in the grid unit system belongs; the displacement solving module is used for carrying out excavation simulation on the three-dimensional geological model based on numerical simulation, and solving the strain components and displacement of the subareas of the residual grids after excavation simulation based on the expansion effect model; the deformation prediction module is used for constructing a correlation data set according to the strain component and the displacement of each grid zone and the corresponding processed basic geology and lithology data, and inputting the correlation data set into a pre-constructed extrusion type large deformation prediction model to obtain a deformation prediction result.
9. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the method of inter-strata extrusion type large deformation prediction of composite lithology of any one of claims 1-7 when the computer program is executed by the processor.
10. A computer readable storage medium having stored thereon a computer program, which when executed by a processor, implements the method of inter-strata extrusion type large deformation prediction of composite lithology according to any one of claims 1-7.

Description

Method and system for predicting extrusion type large deformation of inter-layer stratum of composite lithology Technical Field The invention belongs to the field of stratum deformation prediction, and particularly relates to a method and a system for predicting extrusion type large deformation of a composite lithology interlayer stratum. Background In tunnel engineering construction, the composite stratum (including interbedded layers, interlayers, bedding development areas and the like) has complex lithology combination and large difference in mechanical properties, is easily influenced by expansion effect, capacity expansion effect and aging creep, is extremely easy to generate large deformation disasters, seriously threatens construction safety, delays construction period and increases engineering cost. Therefore, the accurate inversion of the ground stress field of the tunnel site area and the pre-judgment of the stratum deformation in the construction process are core requirements for the safety control of the composite stratum tunnel construction. In the prior art, a single model or a simplified processing mode is adopted for inversion and deformation prediction of the ground stress field, and the method has the defects that firstly, the ground stress field is calculated by relying on a single numerical simulation or a traditional machine learning model, a rough calculation-fine correction hierarchical calculation system is not formed, when the actual measurement data of a small sample are faced, the calculation accuracy is low easily, secondly, the deformation prediction model does not fully consider the regional mechanical response characteristic of a composite stratum, so that the deviation of a deformation prediction value and an actual measurement value on site is larger, and the support decision cannot be guided accurately. Disclosure of Invention The invention aims to provide a method and a system for predicting extrusion type large deformation of a laminated stratum with composite lithology, which are used for solving the problem of low deformation prediction accuracy in the prior art. In order to achieve the above purpose, the present invention adopts the following technical scheme: In a first aspect, the invention provides a method for predicting extrusion type large deformation of a laminated stratum of composite lithology, which comprises the following steps: Acquiring basic geology and lithology data of a target area, preprocessing and integrating the basic geology and lithology data, and obtaining processed basic geology and lithology data; Constructing a three-dimensional geological model of the target area by using the processed basic geology and lithology data, and carrying out grid division on the three-dimensional geological model based on a preset division rule to obtain a grid cell system; inverting stress values of grids of the grid cell system based on a preset twice inversion mechanism to obtain an accurate ground stress field cloud picture of the target area; Performing viscoelastic-plastic partitioning on an accurate stress field cloud image of a target area based on an expansion effect, and determining the type of a partition to which each grid in a grid unit system belongs; performing excavation simulation on the three-dimensional geological model based on numerical simulation, and solving the strain components and displacement of the subareas of the residual grids after the excavation simulation based on the expansion effect model; and constructing a related data set according to the strain component and the displacement of each grid belonging to the partition and the corresponding processed basic geology and lithology data, and inputting the related data set into a pre-constructed extrusion type large-deformation prediction model to obtain a deformation prediction result. Preferably, the basic geology and lithology data comprise stratum structure data, lithology mechanical data, bedding distribution data and ground stress data; The stratum structure data comprises lithology combination type, single lithology single layer thickness and alternating frequency of an interlayer section, main lithology thickness, interlayer lithology type, interlayer thickness and extension length of the interlayer section; The lithologic mechanical data comprises elastic modulus, internal friction jiao, density, cohesive force and poisson ratio of a interlayer section; the bedding distribution data comprises the relative position, the tendency, the spacing and the internal friction jiao of the bedding and the tunnel; The ground stress data comprise a viscosity coefficient, an expansion coefficient, a humidity change maximum value, a permeability coefficient and a dilatation coefficient. Preferably, the two-time inversion mechanism is: extracting basic geology and lithology data of each grid, and constructing feature vectors according to the basic geology and lithology data of each grid; input