复杂地质条件下引水隧洞围岩稳定性分析

地下工程具有广阔的发展前景,而其围岩的稳定性关系到工程的施工安全以及运行安全。采用有限元分析方法,对计算模型的有限变形原理、洞室参数的选择进行了介绍。依托柳坪水电站引水隧洞工程,依据相关设计参数,建立三维整体模型,模拟了复杂地质条件下引水隧洞在开挖不支护、开挖支护完成后、地震工况条件下围岩稳定性计算结果,说明隧洞围岩主要受到压应力的作用,且通过衬砌能有效地控制围岩变形。并对结果对比分析,得出了3种工况的安全系数均大于1,隧洞围岩结构稳定性较好,且引水隧洞垂直方向变形均大大超过水平方向等结论,为施工及结构设计提供参考。

Study on Adjacent Rock's Stability of Diversion Tunnel under Complicated Geology

There is a broad developing prospect for underground tunnel,and the stabilization of its adjacent rock is related to the safety of constrction and running.By using the three-dimensional finite element analysis method,the calculation model is introduced here,including the finite element deforming principle and the choice of chamber parameters.Depending on the diversion tunnel of Liuping Hydropower Station and basing on related design parameters,the whole three-dimensional model is built,and the calculation results are simulated for the adjacent rock's stability of the diversion tunnel under the condition of complicated geology,which is after excavation and supporting and under seismic condition.It is also detailed that the adjacent rock mainly suffered from compression stress,and the deforming could be controlled by lining effectively.At last,the results achieved are contrasted and analyzed to obtain such the conclusions that the assurance factors under three work conditions are all greater than 1,the adjacent rock's stability is good,and the vertical deforming is greater than the horizontal deforming largely.All these could provide references for the construction and structural design of similar projects.