【摘要】 软弱岩石在破坏前后两个阶段分别具有较明显的应变硬化和应变软化特性,岩石破坏后的残余强度不仅取决于力学参数(内摩擦角和内聚力),还取决于侧应力的大小和外界环境因素的影响。本文根据软岩的这些力学性质,对巷道围岩的稳定性进行了分析,结果表明,巷道围岩出现小范围的破坏是有利于降低支护强度的,允许破坏区的大小和所需的支护强度与岩石在破坏阶段的力学特性有重要的关系,由此关系,本文对充分发挥围岩自承作用的问题作了阐述。更多还原

【Abstract】 The soft rock has a marked strain hardening and strain softening features respectively in two stages before and after failure. The residual strength of rock after failure depends not only on mechanical parameters (the internal friction angle and cohesion) , but also on the magnitude of lateral stress and influence of external environment. This paper analyzes stability of surrounding rock of a tunnel on the basis of these mechanical properties. The results have shown that a small failure of country rock is beneficial to reduction of support density. There is an important relation among the extent of the permissible failed zone, and the necessary support density and mechanical properties of rock in different stages of failure. This paper describes the problem of making use of self-supporting capacity of the surrounding rock.更多还原