白象山铁矿河床下开采地表沉降数值模拟分析

针对设计采用嗣后充填采矿法的白象山铁矿的主矿体位于青山河床下的状况,为了保障矿山安全生产,采用数值模拟方法,对矿体、围岩及断层进行建模,对断层采用岩体弱化的方法建立模型,对于重点研究的地表和对结果有影响的断层进行细化网格的划分,并依据设计的连续倾斜进路尾砂充填法对模型进行开采与充填,分析地表沉降情况。通过计算分析,确定了位于地表河流中部即横坐标为400 m处的最大沉降值0.23 m。根据模拟结果,提出了对存在安全隐患的断层注浆加固的处理方法。经过再次运算得出最大沉降值减小到0.15 m,研究结果验证了采矿方法的安全可行性与注浆加固方法的安全有效性。

Numerical Simulation Analysis of Ground Surface Subsidence During Mining of Baixiangshan Iron Mine under a Riverbed

In view of the main orebody of Baixiangshan iron mine is located under Qingshan river.In order to guarantee the safe mining，the numerical simulation method is used to build model of the ore body，surrounding rocks and faults.Faults model is built with rock weakening method.The surface and the faults with large influence are meshed，and then the caving and filling on the model are made by the continuously inclined drift stoping method with tailings backfilling to analyze the situation of surface subsidence.Through analysis and calculation，the maximum settlement value at the central river with the X-coordinate 400m is determined to be 0.23 m.According to the simulation results，an approach for grouting reinforcement of faults in risks was proposed.Through the calculation，the maximum settlement value is reduced to 0.15 m.The results verify the feasibility and safety of mining methods and the safety effectiveness of the grouting reinforcement method.