覆岩离层注浆减沉工程有关技术问题研究

Study on Technical Issues of Grouting in Overburden-separation Project

采用流体力学的理论方法结合相似材料模拟实验研究成果,对覆岩离层形成的过程、注浆时机、注浆压力、浆液在离层空间内的流动规律进行了研究。注浆液在离层空间内的流动形式与离层空间的大小、围岩的渗流特性、工作面的推进速度位置等因素有关,根据实验结果可将浆液在离层空间内的流动分为三种形式:即以钻孔为中心的径向流动;以明渠"挟质"形式流动;以密实挤压形式流动。前两种形式一般发生在离层空间未充满浆液的前提下,而后一种则是在离层空间已被充满时的继续高压注入,即饱和密实挤压注浆充填。只有达到饱和密实充填才能取得理想的注浆效果。

According to the theory of fluid mechanics and the studies of simulation experiments,the process of overburden separation,grouting time,pressure and slurry flow regime are investigated.Due to slurry flow regime in the separation relate to the space size of separation,seepage velocity,mining rate,working face location and other factors,according to the experiments,the pattern of slurry flow can be divided into three patterns.One is radial flow around drilling center.Another is open channel flow bring with granules.And the other is dense flow by the form of squeeze.Generally,the first two flow occurred under the situation of the separation space being not filled with slurry,and the latter is filled with under the situation of continued pressure grouting.The effect of reducing subsidence should be achieved only with compacted fill in separation.