深埋圆形硐室围岩塑性形变压力的广义Hoek- Brown破坏准则解及其三元非线性回归模型

 研究侧压力系数l = 1时，以广义Hoek-Brown经验准则为屈服准则的深埋圆形硐室理想弹塑性围岩的塑性形变压力的闭合解。采用较易获得的围岩参数，分别建立最大塑性形变压力随相对初始应力和归一化地质强度指标变化的二元线性回归模型与相对塑性形变压力随相对初始应力、相对塑性区半径和归一化地质强度指标变化的三元非线性回归模型，为预测围岩塑性形变压力提供较为可靠的途径。

ANALYTICAL SOLUTION FOR PLASTIC DEFORMATION PRESSURE AROUND A DEEP CIRCULAR OPENING BASED ON GENERALIZED HOEK-BROWN FAILURE CRITERION AND ITS TERNARY NONLINEAR REGRESSION MODEL

When λ = 1,a closed-form solution of the plastic deformation pressure in elastic-perfectly plastic surrounding rock obeying the generalized Hoek-Brown failure criterion around a deep circular opening is obtained. Employing the easily-obtained parameters of surrounding rocks,a binary linear regression model for the variation of the maximum plastic deformation pressure with the relative initial stress and the normalized Geological Strength Index(GSI) is established,and so is a ternary nonlinear regression model for the variation of the relative plastic deformation pressure with the relative initial stress,the relative plastic radius and the normalized GSI. The two models can supply a reliable approach for predicting the plastic deformation pressure.