考虑渗透力和原始Hoek-Brown屈服准则时圆形洞室解析解

采用原始Hoek-Brown非线性屈服准则,推导了渗透力作用下圆形洞室弹塑性解析表达式。根据解析公式,绘制了渗透力作用下基于原始Hoek-Brown屈服准则的围岩特性曲线、塑性区半径与洞壁支护力关系曲线、塑性区半径与围岩自重应力关系曲线,并与基于Mohr-Coulomb屈服准则以及不考虑渗透力的图形进行了对比研究,研究表明:应用原始Hoek-Brown屈服准则求出的洞室径向位移和塑性区半径都大于应用Mohr-Coulomb屈服准则求出的结果;在围岩情况较好的条件下基于原始Hoek-Brown屈服准则计算的塑性区半径远大于基于Mohr-Coulomb屈服准则算出的值;渗流效应对地下洞室的塑性区半径和洞壁径向位移的影响十分显著。

Analytical solution of circular openings subjected to seepage in Hoek-Brown media

Taking into account of seepage force, the elastoplastic solution of circular openings is derived by using Hoek-Brown failure criterion. The ground reaction curve, relation curve between radius of plastic zone and supporting force of tunnel wall and relation curve between radius of plastic zone and gravity stress of rock mass based on Hoek-Brown failure criterion are drawn, with seepage being considered. By comparing with the curves based on Mohr-Coulomb yield criterion and the curves without considering seepage, we concluded that: the radial displacement of tunnel wall and radius of plastic zone by Hoek-Brown failure criterion are larger than the results by Mohr-Coulomb yield criterion. For good quality rock masses, the radius of plastic zone based on Hoek-Brown failure criterion is much larger than the results by Mohr-Coulomb criterion. The effect of seepage effect on the radius of plastic zone and radial displacement of tunnel wall for underground opening is significant.