水力测试法在煤层底板破坏探测试验中的应用

Application of Hydraulic Test Method in Floor Damage Test of Coal Seam

针对团柏煤矿下组10#煤带压开采的现状,对该煤层10-115工作面开采引起的底板破坏深度采用水力测试法进行了探测。结果表明:①从定压进水量测试结果看,在煤层开采过程中底板岩层因矿压增减发生了裂隙收缩与扩张,采面距在0～25 m阶段底板最为薄弱,此后底板裂隙进入收缩的恢复阶段,但裂隙的闭合性又远远低于原始状态;②从起始水压测试结果看,10#煤底板的矿压直接破坏深度为9.4 m,其下的扰动带岩层抗水压强度明显减弱,矿压与扰动破坏深度共计12 m。

Aiming at the status quo of 10^# coal seam mining under safe water pressure of aquifer in lower series coal of Tuanbai Coal Mine,hydraulic test method was applied to detect the damage depth of the 10^# coal seam floor due to mining in 10-115 working face. The results show that there is a process of fractures shrink and expansion due to mine pressure increasing or decreasing during coal mining according to test results of the constant pressure water inflow. Coal floor where is apart from mining face between 0 to 25 meters is the weakest. Later, floor fractures began to shrink, however, the closure extent of these fractures was lower than original state. It is shown from the test results of starting water pressure that the direct fractural depth in floor due to the 10^# coal seam mining is 9.4 meters,the capability of anti-hydraulic pressure of the rock layer decreases obviously in disturbance belt under coal floor. The total depth of rock pressure damage and fractural depth is 12 meters.