基于经验强度准则的有压隧洞覆岩厚度计算

Calculation of Overlay Strata Thickness of the Tunnel with Pressure Based on the Experienced Strength Criterion

对塑性岩体中的有压隧洞而言,根据岩体的强度特性和内压力的大小,通过控制塑性区半径,精确确定最小上覆岩层厚度是非常重要的。在对经典的Jeager方法评述的基础上,基于Hoek-B rown强度准则对岩体破坏的表述和Hoek于1980年所做的假设,以弹塑性理论推导了塑性区应力、塑性区半径、最小上覆岩层厚度的计算公式,并以简单算例说明其应用方法。

To the tunnel with pressure in plastic rock body, it is very important to determine accurately the thickness of the smallest overlay stratum by controlling the radius of plastic zone, according to the intensity and the value of inner pressure of rock body. On the basis of the comment on classical geager method and the description of Hoek- Brown strength criterion to the destroy of rock body and the assumption supposed by Hoek in 1980, the calculation formulas of the stress in plastic area, the radius of plastic zone and the smallest overlay stratum thickness are deduced with the elastic - plastic theory and the application method is explained with an simple example.