【摘要】 基于线性Mohr-Coulomb(M-C)强度准则,改进考虑水-力耦合作用下应变软化围岩深埋圆形隧道的应力与位移求解的逐步位移法。该方法全面考虑水-力耦合作用下围岩强度和变形参数的劣化、剪胀角和塑性区内弹性应变的变化。基于平面应变的假设和改进的逐步位移法,将整个塑性区分为n个同心圆环,以弹塑性交界面处的应力应变作为塑性区的初始值,获得塑性区内的应力及位移解。同时,对水-力耦合作用下的强度及变形参数进行分析。研究结果表明:在考虑水-力耦合作用下,应力减小,收敛和塑性半径均变大,位移与塑性半径提高幅值分别为27.00%和3.17%。更多还原

【Abstract】 An improved numerical stepwise procedure for the stress and displacement of a deep-buried circular opening excavated in a strain-softening rock mass under hydraulic-mechanical coupling was proposed. It followed the generalized Mohr-Coulomb(M-C) failure criterion. This method considered the deterioration of the strength, deformation, dilation angle and the variation of elastic strain in the plastic region. The total plastic region was presumably divided into n concentric annuli based on the assumption of plane strain and improved numerical stepwise procedure. The stress and displacement on each ring were expressed by the recursive relation from the initial value of the outermost annulus. Meanwhile, parametric studies were also conducted to highlight the influence of hydraulic-mechanical coupling on stress and displacement. The results show that the stress confinement is lower, and displacement and plastic radius are higher than those obtained when hydraulic-mechanical coupling is not considered. Displacement and plastic radius increase by 27.00% and 3.17%, respectively.更多还原