Mechanism And Technology Of Failure Of Rock Rodaway Support In High Stress Weak Surrounding Rock

This paper aiming at the problem of Xiaoyun coal mine high stress soft roadway in support and reinforcement, mainly in high stress soft roadway surrounding rock instability mechanism and its supporting technology as the research object. Based on comprehensive study through multidisciplinary and multiple methods, this paper puts forward a new method of repairing the surrounding rock by using the combined support technology of "compressible U steel shed (frame) + anchor +anchor rope+delayed grouting". The technology has achieved good reinforcement effect.Xiaoyun coal mine east wing track roadway surrounding rock supporting existing poor surrounding rock condition, mining stress and tectonic stress increase , impact strength increasing etc , it has the characteristics of large deformation and rheology, the roadway has been in the process of deformation and failure, the deformation law can be divided into three periods: rapid deformation period, stable deformation period and rheological deformation period. Because of the rheological and hulking deformation of roadway surrounding rock is very obvious,the supporting system is subject to large deformation pressure , if the support system can not be compressed in time, the deformation pressure makes the surrounding rock damage and change into the loose pressure,it is likely to make the support system deformation and lose effect, and this is where the deformation failure mechanism of roadway engineering.Based on the research results of roadway surrounding rock characteristics and surrounding rock instability mechanism, in Xiaoyun coal mine east main roadway control problems, adopt "compressible U steel shed (frame) + anchor + anchor rope+delayed grouting" retaining technology. In order to verify its feasibility, the computer simulation and comparative analysis are carried out by using FLAC3D numerical analysis software , and the simulation has confirmed four supporting scheme. Simulation results show that Plan 4 "compressible U steel shed(frame) + anchor + anchor rope+delayed grouting" can form stable bearing ring, to realize the same level of hierarchical reinforcement and make timely high resistance of supporting pressure condition, to ensure long-term stability of the roadway.In the engineering practice, the plan of "compressible U steel shed(frame) + anchor + anchor rope+delayed grouting" is carried out, and the supporting effect is monitored and analyzed. Site monitoring and data show that the support of "compressible U steel shed (frame) + anchor +anchor rope+delayed grouting" can meet the requirements of the production section. After reinforcement treatment, the deformation of roadway surrounding rock is greatly reduced and tends to be stable, the relative displacement of the top and bottom plate is 115mm, and the relative displacement of the two groups is 92mm, compared with the surrounding rock of the tunnel, the stability has been greatly improved.At the same time, the force of bolt and anchor rope is more reasonable.