Stereoscopic identification method and apparatus for disturbance stress evolution process of underground cave surrounding rock

Patent metadata

Field	Value
Publication number	US-12352914-B2
Application number	US-202218051503-A
Country	US
Kind code	B2
Filing date	Oct 31, 2022
Priority date	Apr 12, 2022
Publication date	Jul 8, 2025
Grant date	Jul 8, 2025

Abstract

A stereoscopic identification method and apparatus for disturbance stress evolution process of underground cave surrounding rock perform a numerical inverse analysis of three-dimensional stereoscopic disturbance stress of a surrounding rock of the target underground cave on the basis of measurement values of three-component microseismometers and disturbance stress gauges. During the analysis, the overall prediction values are corrected from point to volume based on the measurement values to achieve a high-precision identification effect of the evolution process of the stereoscopic disturbance stress of the surrounding rock.

First claim

What is claimed is:

1. A stereoscopic identification method for disturbance stress evolution process of rock that surrounds an underground cave, comprising:
collecting rock structural characteristics of a borehole between a target underground cave of which the disturbance stress evolution process is to be measured and a nearby excavated cave through a borehole camera before the target underground cave is excavated;
collecting rock fracture vibration wave information on the periphery of the borehole through a three-component microseismometer placed in the borehole between the target underground cave and the nearby excavated cave during the process of excavating the target underground cave;
calculating microseismic apparent stress evolution information at each source location of rock fracture based on the rock fracture vibration wave information;
collecting disturbance stress evolution information, at a position where a disturbance stress gauge is mounted, through the disturbance stress gauge placed in the borehole during the process of excavating the target underground cave; and
performing a numerical inverse analysis of three-dimensional stereoscopic disturbance stress of a surrounding rock of the target underground cave in combination with the rock structural characteristics of the borehole, the microseismic apparent stress evolution information at each source location of rock fracture, and the disturbance stress evolution information at a position where the disturbance stress gauge is mounted, the result of analysis being taken as a stereoscopic identification result of the disturbance stress evolution process of rock that surrounds an underground cave of the target underground cave.

2. The method according to claim 1 , wherein the three-component microseismometer includes a first three-component microseismometer and a second three-component microseismometer; the disturbance stress gauge includes a first disturbance stress gauge, a second disturbance stress gauge and a third disturbance stress gauge; the first three-component microseismometer, the first disturbance stress gauge, the second disturbance stress gauge, the third disturbance stress gauge, and the second three-component microseismometer are placed in the borehole in order in a direction from the target underground cave to the nearby excavated cave;
during a placing process, the first three-component microseismometer, the first disturbance stress gauge, the second disturbance stress gauge, the third disturbance stress gauge, and the second three-component microseismometer are pushed into corresponding positions in order by a pusher and then the pusher is withdrawn.

3. The method according to claim 2 , wherein a process of positioning a source location of rock fracture comprises:
measuring spatial coordinates of the first three-component microseismometer and the second three-component microseismometer, respectively;
obtaining vibration wave information collected by the first three-component microseismometer and the second three-component microseismometer; and
determining the source location of rock fracture based on an overlapping position of the vibration wave information collected by the first three-component microseismometer and the second three-component microseismometer under a propagation positioning mechanism.

4. The method according to claim 2 , wherein distances from the first three-component microseismometer, the first disturbance stress gauge, the second disturbance stress gauge, the third disturbance stress gauge, and the second three-component microseismometer to a surface of a surrounding rock of the target underground cave are 0.5 m, 1 m, 3 m, 7 m, and 8 m, respectively.

5. The method according to claim 1 , further comprising:
performing a full-hole grouting in the borehole to complete placement after the three-component microseismometers and the disturbance stress gauges are placed at corresponding positions in the borehole.

6. The method according to claim 1 , wherein during the numerical inverse analysis of three-dimensional stereoscopic disturbance stress of the surrounding rock of the target underground cave, performing the following analysis based on an established numerical computing grid for the underground cave, wherein the grid is refined at positions adjacent to a surface of rock that surrounds an underground cave and the borehole:
performing underground cave excavation simulation to calculate a preliminary simulation result of the disturbance stress evolution process during the process of excavating the target underground cave;
performing an inverse-analysis on values of ground stress and material parameters involved in the preliminary simulation result of the disturbance stress evolution process by taking the rock structural characteristics of the borehole, the microseismic apparent stress evolution information at each source location of rock fracture, and the disturbance stress evolution information at a position where the disturbance stress gauge is mounted as basic data, and outputting a target simulation result of the disturbance stress evolution process which conforms to the three of the rock structural characteristics of the borehole, the microseismic apparent stress evolution information at each source location of rock fracture, and the disturbance stress evolution information at a position where the disturbance stress gauge is mounted as a stereoscopic identification result of the disturbance stress evolution process of rock that surrounds an underground cave of the target underground cave.

7. The method according to claim 6 , wherein, during the numerical inverse analysis of three-dimensional stereoscopic disturbance stress of the surrounding rock of the target underground cave, target functions are set with deviations between simulation values and the microseismic apparent stress evolution information at each source location of rock fracture and the disturbance stress evolution information at a position where the disturbance stress gauge is mounted, and then a relationship between parameters for inverse-analysis and the target functions is established with a mechanism of backpropagation neural networks, and optimization is performed with a gradient descent algorithm, and finally updated simulation values are caused to conform to the three of the rock structural characteristics of the borehole, the microseismic apparent stress evolution information at each source location of rock fracture, and the disturbance stress evolution information at a position where the disturbance stress gauge is mounted.

8. A stereoscopic identification apparatus for disturbance stress evolution process of rock that surrounds an underground cave, comprising a processor and a memory stored with computer programs, wherein the processor, when calling the computer programs in the memory, implements the method of claim 1 .

9. A computer readable storage medium, comprising a plurality of instructions stored thereon, wherein the instructions are adapted to be loaded by a processor to implement the method of claim 1 .

Assignees

• Inst Rock & Soil Mech Cas

Inventors

• Li Shaojun
• Feng Guangliang
• Zheng Minzong

Classifications

• G01V1/30 Primary

  Analysis (G01V1/50 takes precedence) · CPC title

• G01V1/288 Primary

  Event detection in seismic signals, e.g. microseismics (G01V1/36 takes precedence) · CPC title

• G06F16/215

  Improving data quality; Data cleansing, e.g. de-duplication, removing invalid entries or correcting typographical errors · CPC title

• G06F2119/14

  Force analysis or force optimisation, e.g. static or dynamic forces · CPC title

• G16C10/00

  Computational theoretical chemistry, i.e. ICT specially adapted for theoretical aspects of quantum chemistry, molecular mechanics, molecular dynamics or the like · CPC title