考虑各向异性、剪胀和渗流的柱孔扩张问题统一解

基于统一强度理论，考虑渗流、各向异性、剪胀特性以及中主应力等因素的综合影响，推导了柱孔扩张问题弹塑性解答。结果表明，富水条件下的扩孔问题中考虑渗流体积力的影响是非常有必要的，不考虑渗流影响的扩孔压力比实际工程偏小；渗流体积力越大，塑性区半径越小。另外，传统的扩孔解答假定土体为各向同性初始应力状态高估了极限扩孔压力，也低估了扩孔过程中圆孔周边的塑性区范围，造成工程安全等级偏低。该结果为海底圆形隧道以及渗流条件下地下水平构筑物施工弹塑性分析提供了理论依据，对工程设计具有一定参考价值。

Unified solutions of cylindrical cavity expansion considering anisotropy, shear dilation and seepage

Based on the unified strength theory, analytical elastoplastic solutions for cylindrical cavity expansion are deduced considering seepage, anisotropy, shear dilation and intermediate principal stress. Case study results indicate that it is necessary to consider the effect of volumetric force of seepage on the expansion pressure under rich water condition; and the expansion pressure without considering the seepage is smaller than the engineering practice. The radius of plastic zone would be smaller with the increase of seepage volumetric force. In addition, the traditional analytical solutions of cavity expansion which are based on the isotropic initial stress state supposition overestimate the ultimate expansion pressure and underestimate the plastic zone field around the cavity; and this would result in lower engineering safe class. The results provide some reference value for engineering design and a theory base for the elastoplastic analysis of subsea circular tunnel and other underground horizontal construction under seepage condition.