经验强度准则确定有压隧硐上覆岩层最小厚度的方法

水工建筑中,据岩体的强度特性和内水压力的大小,精确确定有压隧硐上覆岩层最小厚度是非常重要的。文章在对经典方法进行评述的基础上,引入反映岩体非线性破坏特征的经验强度准则,视有压隧硐为内水压力和岩体初始应力联合作用的弹性体,据经验准则对岩体破坏的表述,理论推导了坚硬无裂缝岩体中有压隧硐上覆岩层最小厚度计算公式。最后,以简单算例说明文中方法。

METHOD OF DETERMINING OVERLYING STRATA MINIMUM THICKNESS OF TUNNEL IN HYDRAULIC ENGINEERING WITH HOEK-BROWN STRENGTH CRITERION

As an important piece of work in hydraulic engineering, it is the key to determine the minimum thickness of overlying rock formation of the tunnel under pressure. On the basis of introducing the method of calculating the stress of surrounding rocks and the failure character of rock mass, the authors derived the equation of determining the minimum thickness of overlying rock formation with the Hoek-Brown strength criterion. In order to explain the method, an example is offered in the paper. It is shown that the method can not only determine the minimum and maximum thickness of overlying rock formation, but also decide the failure and stability of tunnel. So it is available to engineering practice in the future after proved.