近水平矿体回采顶板覆岩冒落规律分析

Analyses on Roof Overburden Strata Collapse of Remained-slope Mining

针对近水平矿体回采过程中顶板持续垮冒、覆岩沉降及破坏这一复杂的应力重分布、变形和破坏的过程,借助RFPA数值模拟软件,考虑岩体的碎胀效应,以及围岩的不同本构关系,对顶板覆岩的冒落过程进行数值模拟。研究结果表明,碎胀后的岩体对上覆岩层会有一个支撑反力;所以考虑碎胀效应的两方案结果与参考文献相符,并得到了不同计算方案的冒落高度值。所得结果为矿体安全开采提供理论依据,并对认识和研究采场覆岩冒落规律具有一定的借鉴意义。

The caving process of remained-slope mining is a stress redistribution,deformation and failure process. It is also a complex process with the continuous caving of the roof,subsidence and failure of the overburden strata. According to this,it is simulated by RFPA code when the effect of expansion of broken rock mass and the constitutive relation of surrounding rock mass is taken into account. The results show that the results of schemes considering the broken expansion of rock are similar to that of the reference because the overburden strata is given a supporting reaction by the broken rock. The caving heights are obtained under different conditions. The results provide theoretical basis for safe mining. Moreover,it is good for the knowledge and study of the stope overburden strata caving.