【摘要】 基于峰值应力后具拐点的应变非线性软化本构模型,且同时考虑中间主应力2s,对岩体形变影响的条件下及等压荷载下圆形硐室围岩塑性区应力分布规律、围岩承载机制及围岩与支护之间作用关系进行研究,得到无支护硐室围岩自承地应力上确界{}ossupp、围岩压力下确界{}ainfp等反映实际硐室围岩工作状况的重要概念。给出了{}ossupp、{}ainfp的表达式以及它们与地应力op间的关系式。所得到的塑性区应力、塑性区半径、围岩压力和硐室周边位移等研究结果,与基于理想弹塑性体的Fenner解答相比,要更接近实际硐室围岩中的对应量值。更多还原

【Abstract】 Under the conditions of according with strain nonlinear softening constitutive model of having inflexion point after peak stress of practical rock and considering rock deformation influence due to intermediate principal stress2s,stress distribution laws of surrounding rock plastic zone of circular cavern under the condition of uniform pressure,the mechanism of load bearing and acting relation between surrounding rock and support are studied. Some important conceptions of working status of practical cavern surrounding rock are obtained;such superior certain limit sup{pos} of self-support geo-stress and inferior certain limit inf{pa} of supportless cavern surrounding rock. The expressions of sup{pos}, inf{pa} and the relation formula between sup{pos}and geo-stress 0p,between inf{pa}and geo-stress p0 are given. The research results of plastic zone stress,plastic zone radius,surrounding rock pressure,and surrounding rock displacement are more nearly actual correspondence values of cavern surrounding rock with Fenner solution based on ideal elastoplastic materials.更多还原