The present paper aims to establish a versatile strength theory suitable for elasto-plastic analysis of underground tunnel surrounding rock. In order to analyze the effects of intermediate principal stress and the roc...The present paper aims to establish a versatile strength theory suitable for elasto-plastic analysis of underground tunnel surrounding rock. In order to analyze the effects of intermediate principal stress and the rock properties on its deformation and failure of rock mass, the generalized nonlinear unified strength theory and elasto-plastic mechanics are used to deduce analytic solution of the radius and stress of tunnel plastic zone and the periphery displacement of tunnel under uniform ground stress field. The results show that: intermediate principal stress coefficient b has significant effect on the plastic range,the magnitude of stress and surrounding rock pressure. Then, the results are compared with the unified strength criterion solution and Mohr–Coulomb criterion solution, and concluded that the generalized nonlinear unified strength criterion is more applicable to elasto-plastic analysis of underground tunnel surrounding rock.展开更多
文摘The present paper aims to establish a versatile strength theory suitable for elasto-plastic analysis of underground tunnel surrounding rock. In order to analyze the effects of intermediate principal stress and the rock properties on its deformation and failure of rock mass, the generalized nonlinear unified strength theory and elasto-plastic mechanics are used to deduce analytic solution of the radius and stress of tunnel plastic zone and the periphery displacement of tunnel under uniform ground stress field. The results show that: intermediate principal stress coefficient b has significant effect on the plastic range,the magnitude of stress and surrounding rock pressure. Then, the results are compared with the unified strength criterion solution and Mohr–Coulomb criterion solution, and concluded that the generalized nonlinear unified strength criterion is more applicable to elasto-plastic analysis of underground tunnel surrounding rock.
文摘首先,使用ABAQUS软件,分析研究了超高层钢框架-钢板核心筒结构(宁夏电视塔方案III)的动力特性。数值结果表明:结构方案III的侧向刚度比钢框架-支撑核心筒结构(方案I)大,扭平周期比减小,扭转效应相应地减弱。钢板剪力墙的条带模型(Strip Model,SM)不仅能准确地模拟出钢板的屈曲后行为,而且能明显地节省计算资源。因此,接着,基于开发出的抗震钢板剪力墙条带模型用户单元子程序(称为UEL for SM),进行9度罕遇地震(620 cm/s2)作用下结构的弹塑性动力时程分析,以检查结构的变形指标和塑性发展情况。数值结果表明:结构的最大层间位移角出现在中部楼层段,结构构件的屈服机制合理体现多道抗震防线。
