Deformation features and failure mechanism of steep rock slope under the mining activities and rainfall

Underground mining activities and rainfall have potential important influence on the initiation and reactivation of the slope deformations,especially on the steep rock slope. In this paper,using the discrete element method(UDEC),numerical simulation was carried out to investigate deformation features and the failure mechanism of the steep rock slope under mining activities and rainfall. A steep rock slope numerical model was created based on a case study at the Wulong area in Chongqing city,China. Mechanical parameters of the rock mass have been determined by situ measurements and laboratory measurements. A preliminary site monitoring system has been realized,aiming at getting structure movements and stresses of unstablerock masses at the most significant discontinuities. According to the numerical model calibrated based on the monitoring data,four types of operation conditions are designed to reveal the effect of mining excavation and extreme rainfall on the deformation of the steep rock slope.

金山店铁矿地下开采引起地表变形规律的离散元模拟研究

用离散单元法对金山店矿山进行了二维模拟研究,得到了其围岩变形规律,且计算结果为圈定地表的移动和陷落范围提供了可靠的依据;同时,对离散元方法的应用,特别是参数选取进行了有益的探讨。

基于数值积分法的地下开采地表变形预测算法

为降低地表变形中竖向位移与水平位移的预测误差,提出基于数值积分法的地下开采地表变形预测算法。根据数值积分法的基本原理,计算地表下沉值、倾斜状况、剪切值、曲率以及竖向位移与水平位移,并依据该算法旋转调整坐标系,同时调整拐点中存在的偏距问题,使理论坐标系旋转为现实开采中的坐标系。结合计算得到的地表变形参数,采用剖面线填充算法分割地表变形作业面,并将分割后的作业面转化为一系列的小矩形,通过叠加小矩形的形式,实现地表变形的预测。经实验验证:上述算法预测地表下沉值、曲率值与倾斜值均与实际结果较为接近,且对不同开采深度与开采宽度的地表水平位移、地表竖向位移预测结果与实际值十分接近,未出现较大误差。