隧道地应力测试及岩爆预测研究

Research on in-situ stress measurement and rockburst forecast in tunnels

高地应力以及由此诱发的地质灾害(如岩爆等)是目前隧道施工中经常遇到的工程地质问题,地应力测试则是进行隧道岩爆及其其他灾害预测预报的重要内容,利用岩石声发射Kaiser效应测试地应力应用较为广泛,作者采用岩石声发射Kaiser效应法对隧道岩体初始地应力场进行了测试,结果表明,笔架山隧道应力总体状态为稳定型,岩体应力量级普遍较低。利用所测得的地应力场数据,结合国内外相关岩爆判据判定和理论分析,进一步得出笔架山隧道不会发生岩爆的结论。通过2D-σ有限元数值模拟,对笔架山隧道开挖中是否会产生岩爆等施工地质灾害做出了最终的判定,这种综合预测方法的准确性和可靠性较以前单一的岩爆预测方法大大提高,在岩爆预测理论和工程应用方面具有很好的参考价值。

High in-situ stress with some geological disasters induced, such as rockburst and large deformation, is an serious engineering problem always happening in tunnel construction, however, in-situ stress measurement is an important factor for the forecast of rock burst and other geological disasters; a test method using Kaiser effect of rock is being used widely at present. In the paper, the initial geo-stress field was researched by the method of Kaiser effect measurement; the numerical value and orientation of in-situ stress was gotten, and those results proved that the stress state of the tunnel is stable; the in-situ stress was being at a low lever, then this results was used in the criterion for rock burst and some theoretical analysis, the conclusion that rock burst will not appear was taken. Finally, through numerical simulation by 2D-σ software, the conclusion upwards was also validated. In a conclusion, the poly-method of rockburst forecast is prior to other single method in veracity and reliability, and is valuable in the theory and engineering application of rockburst forecast.