Study On The Failure Law Of The Surrounding Rock Of Highway Tunnel

Stability of the surrounding rock is crucial in the process of the highway tunnel construction,once surrounding rock instability,it can damage equipments in the room of hydroelectric station,traffic tunnel and mining gallery.Surrounding rock instability also threaten engineers′personal security.Therefore,research tunnel stability have significance in underground space for the effective and rational development,optimization and construction to ensure the project smoothly conducted.This paper depends on The Qin Ling Zhong Nan mountain highway tunnel,the tunnel deeply buried(800.0m),longly lines(18.02×2km),and complex geological conditions.Mixed gneiss which is brittleness and in high geo-stress level is the main rock in the tunnel.It is prone to accour dynamic rock burst and zonal fracturing phenomenon.Based on the definition of deep and under high geo-stress deep rock masses mechanical properties research at home and abroad,this paper quo two characteristic scientific phenomenona,which are rock burst and zonal fracturing phenomenon.With Zhong Nan mountain tunnel project overview,the paper from MTS-AE rock mechanics experiment,acoustic emission and drilling in the site and numerical analysis using the FLAC3D numberical analysis software three aspects to research rock burst problem,discovering the law of the"time-space-strength"in deep rock burst and exploring zonal fracturing phenomenon in the deep rock masses.This paper conclud the top and the bottom appear the area of high stress on the analysis of secondary stress in circular tunnel,which are met two conditions of rock burst occurrence:①rock body reserves sufficient elastic strain energy;②damage caused by the stress concentration.Conclud rock burst acoustic emission characteristics and the dynamic evolution by acoustic emission forecasting technology.From the numerical analysis using the FLAC3D numerical analysis software,in the process of tunnel ventilation construction,the more near to main tunnel place,the bigger disturbance on rock nearby,the more subsidence tunnel ventilation upper stratum,but the sphere of disturbance is same to the former tunnel constrution′s,and continuously reache to the rock depth.Rock burst is a release of energy,both gradual process and mutation process.Rock burst occurrence directly related to excavation and support measures,so carried out rock burst control measures provide a reliable basis with the phenomenon of rock burst prevention in high geo-stress deep rock masses,and also has important in theoretical and engineering application values.