极高应力条件下岩体开挖面应力测量方法研究

RESEARCH ON MEASUREMENT METHOD FOR STRESS OF ROCK EXCAVATION SURFACE UNDER EXTRA-HIGH STRESS

鉴于现有几种应力测量方法在极高应力(岩体应力与强度比/Rc>0.5)环境下的局限性,提出基于部分恢复变形的切缝解除法测量极高应力条件下岩体表面应力,并从理论模型上说明其确定极高应力的可行性。应用该方法对锦屏二级水电站科研试验洞开展实测研究,实测得到的最大应力可达80 MPa。该方法在测量过程中既不需获取完整岩芯,又不需要超高压力设备。测试设备轻便、操作简单,测量快速,适合于极高应力条件下表面应力测量,可为洞室岩爆防治、支护以及边坡治理提供实测地应力资料。

For the limitations of current in-situ stress measuring methods when they are carried out in high in-situ stress conditions（/ Rc 0.5）,a new goestress measurement method called based on partly restoration slot relief method is proposed to measure in-situ surrounding rock stress in high stress condition,and its feasibility is illustrated by theoretical model.This new method was applied at an experimental tunnel in Jinping II hydropower station,China;and the measured maximum stress is 80 MPa.When the test is carried out,it is not need to obtain intact rock core,meanwhile,the instruments of extra-high pressure is not requried.The device of this method is light weight,the operation is easy and quickly.It can be used to measure in-situ rock stress in high stress condition.it provides measured stress for prevention of the cavern rockburst and slope treatment.