带压开采煤层底板破坏深度数值模拟研究

Research on Numerical Simulation of Seam Floor Destruction Depth under Pressure Mining

伴随煤炭开采深度的加大,带压开采在深部矿井开采中的应用越来越广泛。以金庄煤矿北二盘区的首采面为工程背景,利用FLAC数值模拟软件分析煤层开采过程中底板应力及破坏特征,采用经验公式预计和现场地质雷达探测2种方法得到底板破坏深度。结果表明:煤层底板下0~10 m内岩体破坏较为严重,不具备阻水能力;煤层底板下10~25 m内岩体虽发生了局部破坏,具备一定的阻水能力。由经验公式预计和现场地质雷达探测得到底板破坏深度分别为22.36 m和25 m,综合3种测定结果,确定底板破坏深度为25 m。

With the increasing depth of coal mining, the application of mining with pressure in deep mine mining is very widely. Takes the initial surface mining in north second disc region of Jinzhuang coal mine as engineering background, uses FLAC numerical simulation software to analyze the stress and damage bottom seam mining process characteristics, uses empirical formula and field geological radar to get the depth of floor damage. The results showed that: under the coal floor within 0 ~10 m,more serious damage to the rock that it do not have water-blocking ability; Within 10~25 m under the coal floor, the occurrence of localized damage, but the extent of the damage is relatively low with a certain ability to block water. Expected by the empirical formula and field geological radar to get the depth of floor damage was 22.36 m and 25 m. Consolidated results of three assays to determine the depth of floor damage 25 m.