超深竖井掘进岩爆特征及防治措施

Characteristics and prevention and control measures of rock burst in excavation of ultra-deep shaft

由于会泽矿3#超深竖井(施工深度达1 526 m)的工程地质条件,在竖井开挖到一定深度后有不同程度的岩爆现象显现,其中两次比较严重的岩爆发生的位置埋深较深,井筒深度达到1 400 m以上。为此建立了井壁地应力监测系统,对岩爆的发生进行预测。根据井壁周边不同深度布置的4个点处的应力变化曲线分析,总结了地应力分布规律,4#位置(东偏南70°)井壁受测压力最大,最大水平主应力可以达到120 MPa以上,其方位与最大主应力方向相符。结合3#竖井工程岩爆现象的分析,以及岩爆发生的特征,给出了预防岩爆所采取的工程措施,为此类工程施工制定岩爆防治措施提供了科学依据。

Due to the engineering geological conditions of 3# ultra-deep shaft in Huize Mine（ the construction depth reached1 526 m）,the rock burst phenomena with varying degrees appeared when the shaft excavated to a certain depth,among which,two more serious rock burst occurred in the locations with deeper depth,and the depth of shaft reached above 1 400 m. Therefore,an in-situ stress measurement system of shaft lining was established to predict the occurrence of rock burst.The distribution laws of in-situ stress were summarized according to the analysis on the stress variety curves of four points laid at different depth surrounding the shaft lining. It showed that the measured stress on the shaft lining at 4# position（ east by south 70°） was the largest,the maximum horizontal principal stress could reach above 120 MPa,and its orientation was consistent with the direction of the maximum principal stress. The engineering measures for prevention and control of rock burst were put forward combining with the analysis on rock burst phenomenon of 3 # shaft and the characteristics of rock burst. It can provide scientific basis for formulating the prevention and control measures of rock burst in similar engineering construction.