CN-116611197-B - Sliding type dangerous rock body identification method based on multiple indexes

CN116611197BCN 116611197 BCN116611197 BCN 116611197BCN-116611197-B

Abstract

The invention discloses a multi-index-based sliding type dangerous rock mass judging and identifying method which comprises the steps of obtaining initial cohesive force, internal friction angle, cohesive length, bottom inclination angle, dead weight and other physical mechanical parameters of a rock mass to be judged, obtaining inherent vibration frequency and damping ratio parameters of a sliding type dangerous rock mass structure at different moments after damage, calculating the cohesive force and internal friction angle after damage, calculating stability coefficients, cohesive stability coefficients and cohesive force anti-slip ratio indexes at different moments after damage of the sliding type dangerous rock mass based on the physical mechanical parameters of the rock mass, and judging the sliding type dangerous rock mass to be judged according to preset judging rules based on the stability coefficients, the cohesive stability coefficients and the cohesive force anti-slip ratio indexes to obtain judging and identifying results. The method is suitable for rapid identification and early warning of the sliding type dangerous rock mass, and can provide new technical support for better coping with the sliding type collapse disaster in high-risk areas of geological disasters.

Inventors

DU YAN
LI HENG
ZHANG XIAOYONG
WU ZHIXIANG
CHEN CHEN
LU GUANG
ZHANG HONGDA
HUANG YULE
XIE MOWEN
ZHANG JINGE
LI YUAN
ZHANG LEI
HUANG ZHENGJUN
Huo Leichen

Assignees

北京科技大学

Dates

Publication Date: 20260505
Application Date: 20221208

Claims (3)

1. The sliding type dangerous rock body identification method based on multiple indexes is characterized by comprising the following steps of: the physical and mechanical parameters of the rock mass to be judged are obtained, wherein the physical and mechanical parameters comprise initial cohesive force, internal friction angle, cohesive length, bottom inclination angle and dead weight of the rock mass, and effective normal stress and shear stress on a sliding surface; acquiring natural vibration frequency and damping ratio parameters of a sliding type dangerous rock structure at different times after damage; Calculating the cohesive force and the internal friction angle after injury; Based on physical and mechanical parameters of the rock mass, calculating stability coefficients, bonding stability coefficients and bonding force anti-slip duty ratio indexes at different moments after the sliding type dangerous rock mass is damaged; Based on the stability coefficient, the bonding stability coefficient and the cohesive force anti-slip ratio index, carrying out slip type dangerous rock mass identification on the rock mass to be identified according to a preset identification rule to obtain an identification result; the calculation formula of the cohesion after injury is as follows: ; Wherein, the Is that Real-time cohesive force of the time sliding type dangerous rock structure, For the initial cohesion of the sliding type dangerous rock structure, Is that Instantaneous natural vibration frequency of the moment slip type dangerous rock structure, For the initial natural frequency of the slip type dangerous rock structure, Is that Instantaneous damping ratio of the moment slip type dangerous rock structure, The initial damping ratio is the initial damping ratio of the sliding type dangerous rock body structure; The calculation formula of the internal friction angle after injury is as follows: ; Wherein, the Is that The real-time internal friction angle of the time sliding type dangerous rock structure, Is the initial internal friction angle of the sliding type dangerous rock body structure, Is that Instantaneous damping ratio of the moment slip type dangerous rock structure, The initial damping ratio is the initial damping ratio of the sliding type dangerous rock body structure; The calculation formula of the stability factor SF is: ; Wherein, the Is the first The cohesive force required for the stability of the rock mass of the bar, Is the first Effective normal stresses on the sliding surface of the bar, Is the first The internal friction angle of the rock mass of the bar block, Is the first The bonding length of the strip block is equal to the bonding length of the strip block, Is the first Shear stress on the sliding surface of the bar; the calculation formula of the adhesion stability coefficient CSF is: ; Wherein, the In order to transfer the coefficients of the coefficients, , Is the first The inclination angle of the bottom surface of the strip block, Is the first Inclination angle of the bottom surface of the bar block; To act on the first The cohesive force of the strip block is that, , To act on the first The cohesion of the bar; To act on the first The component of the downward sliding force on the sliding surface of the bar block, , To act on the first A downward sliding component on the sliding surface of the bar block; Is the first The dead weight of the strip block; The number of the strips is the number of the strips; the cohesive force anti-slip duty ratio The calculation formula of (2) is as follows: ; Wherein CSF represents a bond stability factor and SF represents a stability factor; the sliding type dangerous rock mass identification is carried out on the rock mass to be identified according to a preset identification rule based on the stability coefficient, the bonding stability coefficient and the bonding force anti-sliding duty ratio index to obtain an identification result, and the method comprises the following steps: for the calculated stability factor SF, the binding stability factor CSF and the binding force anti-slip duty ratio Analyzing, wherein when SF and CSF are both greater than 1, the rock body has no sliding trend, and the rock body is a stable rock body, when SF is greater than 1 and CSF is less than 1, the rock body has sliding trend, and the rock body is a dangerous rock body, wherein when the rock body is a dangerous rock body, if If the ratio of the long-term strength to the breaking strength of the structural surface is greater than or equal to the ratio, the rock mass is a dangerous rock mass without degradation trend, if The rock mass is a dangerous rock mass with a deterioration tendency when the ratio of the long-term strength to the breaking strength of the structural surface is smaller than that of the structural surface, and when SF and CSF are smaller than 1, the rock mass is broken and slides down to collapse and break.
2. The multi-index-based sliding type dangerous rock mass judging and identifying method as set forth in claim 1, wherein the obtaining the physical and mechanical parameters of the rock mass to be judged and identified includes: And obtaining initial cohesive force, internal friction angle, cohesive length, bottom inclination angle and dead weight of the rock mass to be judged, and effective normal stress and shear stress on the sliding surface through an in-situ test.
3. The multi-index-based sliding type dangerous rock mass judging method according to claim 1, wherein the acquiring of the natural vibration frequency and damping ratio parameters of the sliding type dangerous rock mass structure at different moments after damage comprises the following steps: measuring the natural frequency of the sliding type dangerous rock structure by using a non-contact remote sensing monitoring technology, and calculating the damping ratio of the sliding type dangerous rock structure, wherein the damping ratio is The calculation formula of (2) is as follows: ; Wherein, the Is the energy loss factor of the sliding type dangerous rock structure, Energy dissipation for two cycles of vibration of the sliding type dangerous rock structure, Is the total energy of the sliding type dangerous rock structure system.

Description

Sliding type dangerous rock body identification method based on multiple indexes Technical Field The invention relates to the technical field of slip type dangerous rock body identification and early warning, in particular to a slip type dangerous rock body identification method based on multiple indexes. Background In recent years, more and more projects are being built in complex and variable high mountain canyons. The occurrence probability of rock collapse disasters is increased in the intangible high-steep slopes distributed in the mountain canyons, and the Shi Gongyun-dimensional safety of daily engineering construction is threatened at any time, so that scientific and rapid identification of dangerous rock masses is developed, and the method has extremely strong research significance and application value in the aspect of engineering safety strategic requirements and the aspect of geological disaster early warning prevention of the mountain canyons Gu Ou. In practice, the stable rock mass is very likely to deteriorate the strength index of the rock mass structural surface or the rock bridge under the actions of earthquake, long-term rainfall or construction blasting and the like, and then the stable rock mass is developed into a dangerous rock mass with high risk. These rock masses are generally located on the shallow part of the steep side slope, and the rock mass is huge in quantity and extremely irregular in shape, so that dangerous rock mass judgment workload is heavy and difficult. Through remote sensing technologies such as laser scanning technology, interference aperture synthetic radar, unmanned aerial vehicle aerial photography technology, infrared thermal imaging technology and the like, and matching with an intelligent algorithm, dangerous rock mass can be rapidly and primarily identified in engineering, but the methods are mostly based on macroscopic important area analysis from the angle of mathematical statistics analysis, and do not strictly realize quantitative analysis of dangerous rock mass from the angle of mechanics, and engineers still need to carry out reasonable mechanical evaluation to determine the dangerous rock mass during on-site investigation. At present, in investigation and identification of dangerous rock embodiment sites, engineers often adopt a single mechanical index of a stability coefficient for evaluation, namely, a threshold value which is different from 1.05 to 1.5 is generally set to realize mechanical analysis of dangerous rock mass. Based on the definition of the stability coefficient, the stability coefficient is the ratio of the anti-slip force to the sliding-down force, and can be used for directly indicating whether the rock mass is instable and damaged, but the transition of the rock mass from the stable stage to the separation stage cannot be identified, and the quantitative mechanical judgment of the dangerous rock mass is difficult to realize. The effect of the method in identifying bad geologic bodies such as high-risk rock bodies is still to be further questioned. Disclosure of Invention The invention provides a sliding type dangerous rock mass judging and identifying method based on multiple indexes, which aims to solve the technical problem that quantitative mechanical judging and identifying of dangerous rock mass are difficult to realize in the prior art. In order to solve the technical problems, the invention provides the following technical scheme: in one aspect, the invention provides a sliding type dangerous rock mass identification method based on multiple indexes, which comprises the following steps: acquiring physical mechanical parameters such as initial cohesive force, internal friction angle, cohesive length, bottom inclination angle and dead weight of the rock mass to be judged, effective normal stress and shear stress on a sliding surface; acquiring natural vibration frequency and damping ratio parameters of a sliding type dangerous rock structure at different times after damage; Calculating the cohesive force and the internal friction angle after injury; Calculating stability coefficients, bonding stability coefficients and bonding force anti-slip duty indexes at different moments after the sliding type dangerous rock mass is damaged based on the physical and mechanical parameters of the rock mass; and based on the stability coefficient, the bonding stability coefficient and the cohesive force anti-slip ratio index, carrying out slip type dangerous rock mass identification on the rock mass to be identified according to a preset identification rule, and obtaining an identification result. Further, the obtaining the physical and mechanical parameters corresponding to the rock mass to be determined includes: And obtaining initial cohesive force, internal friction angle, cohesive length, bottom inclination angle and dead weight of the rock mass to be judged, and effective normal stress, shear stress and other physical mechanical parame