孟家岗铁矿开采方案及地表铁路安全研究

根据孟家岗铁矿实际地质情况,有铁路、公路于矿区之间穿过,为最大限度地回收资源和保证上部公路的安全运行,确定了房柱法与胶结充填两种采矿方案。通过岩体宏观结构凋查分析、取样、室内岩石力学试验和工程类比,综合确定岩体及充填体力学参数;并采用有限元力学分析软件Comsol Multiphysics对2种不同的开采方案引起公路地表的沉降高度进行了数值计算,模拟计算结果表明:采用"尾砂+普通水泥+粉煤灰+水"配比方案进行胶结充填采矿法采矿时,5#、6#勘探线范围内铁路处的沉降值均小于30 mm,符合安全规程要求,不会影响地表铁路的正常运营,后期地表位移监测结果也较好地验证了尾砂胶结充填采矿方法的正确性。

Study on Mining Scheme and Surface Railway Safety in Mengjiagang Iron Mine

According to the geological condition in Mengjiagang Iron mine,as well as railway,high-way passing through the mining area,in order to maximize the resource recycling and ensure the trans-portation safety of upper railway,two mining schemes including the cemented filling method and room and pillar method were adopt in this paper.Mechanical parameters of rock mass were comprehensively determined based on rock macrostructure survey,sampling,rock mechanics test and engineering anal-ogy.In addition,the software of Comsol Multiphysics was used to calculate the surface sedimentation height caused by the two different mining schemes.The numerical calculation results show that when using cemented filling mining method with the mix proportion scheme of "tailing + cement + fly ash + water",the sedimentation values of railway surface in the range of No.5 and No.6 exploration lines are all less than 30 mm,which meets the requirement of safety regulations,and will not affect the nor-mal operation of railway on the surface.The validity of cemented filling method with tailings is verified well by later surface displacement monitoring results.