岩土力学Issue(4)：1187-1193,7.
考虑剪胀效应的深埋圆形隧道围岩应变软化弹塑性解
Elastoplastic solutions to strain-softening behavior of surrounding rock masses of deep circular tunnels considering dilatancy effect
摘要
Abstract
The nonlinear volumetric increase of rock masses can influence the safety of tunnel excavation; thus it is important to accurately evaluate the dilation mechanism of surrounding rock masses in the plastic zone. However, most of the existing studies solve the stress and strain states in strain-softening rock masses of deep circular tunnels by using the constant or linear dilation model. In order to overcome this deficiency, based on the finite difference method, a new analysis approach is proposed. It can consider the nonlinear dilatancy effect as well as the strain-softening behavior of surrounding rock masses. Moreover, the calculated results are compared with those from other existing methods to verify the calculation accuracy of the proposed method. And then a further study is made to investigate the influence factors of the dilatancy coefficient in the plastic zone with different qualities and support pressures of limestone rock masses, and to compare deformations of surrounding rock masses by the constant and nonlinear dilation models. The results indicate that: for rock masses with lower value of geotechnical strength index (GSI) and poor quality, the confining stress primarily controls the degree of the dilation in the plastic zone; and the deformations at the opening surface with constant and nonlinear dilation models distinguish greatly.关键词
非线性剪胀效应/应变软化特性/有限差分法/剪胀系数Key words
nonlinear dilatancy effect/strain-softening behavior/finite difference method/dilatancy coefficient分类
交通工程引用本文复制引用
崔岚,郑俊杰,章荣军,张威..考虑剪胀效应的深埋圆形隧道围岩应变软化弹塑性解[J].岩土力学,2014,(4):1187-1193,7.基金项目
新世纪优秀人才支持计划资助项目(No. NCET-06-619)。 （No. NCET-06-619）
