露天煤矿边坡中软弱夹层的蠕动变形特性分析

Study on Non Linear Creep Property of Weak Layer in Slope of Open Pit Coal Mine

软弱夹层非线性蠕动变形特征分析，明确了其力学强度的变化、本构关系的非线性特征·根据老化理论提出了软弱夹层的一般流变方程，确定由等速蠕变向加速蠕变过渡的临界应变量作为破坏时刻的破坏应变量，从而建立长期抗剪强度与应力作用时间变化的关系，对于非稳定蠕动变形，等速蠕变阶段的应变速率与剪应力超过长期极限强度的程度有关。

The non linear creep property of the weak layer was analyzed and the change property of its mechanics strength and the non linear property of its stress strain relationship were indicated. On the basis of the aged theory, a common creep equation was proposed. Subsequently, the damage strain was defined as critical value from the steady state creep rate to the increasing state creep rate, and the relationship between the long term shear strength and the stress changing rate with time was concluded. As to the instability deformation of the creep slope, the strain rate of the steady state creep is associated with its shear stress level to exceed its shear strength limit.