裂隙岩体应力渗流耦合模型在压力隧洞工程中的应用

HYDROMECHANICAL COUPLED MODEL OF JOINTED ROCK MASS AND ITS APPLICATION TO PRESSURE TUNNELS

首先,通过三维有限元方法数值模拟山西万家寨引黄工程高压出水岔管在通水期间围岩和衬砌中的渗流场特征;然后,结合工程通水期间渗压计和多点位移计的监测结果,分析岔管衬砌和围岩内的渗透压力的分布规律及岔管围岩的位移场变化规律。工程实践表明:在围岩弹性模量小于钢筋混凝土弹性模量的情况以及满足围岩的水力劈裂压力大于岔管内压的条件下,岔管钢筋混凝土衬砌方案是切实可行的。研究成果对其他类似工程的设计和施工具有一定的指导作用。

Water flow in fractured rock mass is commonly cared about in most rock engineering cases. Based on 3D FEM numerical analysis, seepage characteristics in rock and concrete lining of outlet bifurcation in Shanxi Yellow River Diversion Project under high inner water pressure are obtained. Furthermore, via field measurements of pore water pressure by osmotic pressure gauge in concrete lining and displacements in surrounding rocks by multi-point extensometers, it can be concluded that the variation law of water pressures in concrete from field measurements are quite similar with those from numerical results. The research results show that the reinforced concrete lining should be adopted in the case of elastic modulus of rock mass less than that of concrete, even when the hydraulic jacking pressure of rock mass is greater than the inner water pressure. The conclusions from the research work can be adopted in other similar tunnel engineering.