厚松散层薄基岩煤层开采地表沉降速度及其影响因素研究

Research on surface subsidence velocity and influencing factors by coal mining under thick loose layers and thin bedrock

为研究厚松散层薄基岩煤层开采引起的地表沉降速度变化规律,以淮南矿区某矿110801首采工作面为工程背景,采用有限差分软件FLAC3D分别对不同开采速度、采高、采宽、松散层厚度和基岩层厚度条件下煤层开采地表沉降速度进行模拟研究,分析地表沉降速度变化规律及各影响参数对地表沉降速度的敏感性大小。结果表明:地表沉降速度随开采速度、采高、采宽的增大而增大,但随基岩层厚度、松散层厚度的增大而减小;地表最大沉降速度随开采速度、采高、采宽的增大而线性增大,随松散层厚度的增大而线性减小,与基岩层厚度呈幂函数减小关系;各影响因素对地表最大沉降速度的敏感性从大到小依次为采宽、基岩层厚度、松散层厚度、开采速度、采高。

To study the law of surface subsidence velocity caused by coal seam mining under thick and loose layers and thin bedrock,taking the 110801 first mining face of a mine in Huainan Mining Area as the engineering background,the finite difference software FLAC3D was used to simulate the surface subsidence velocity of coal mining under the conditions of different mining speed,mining height,mining width,loose layer thickness and bedrock layer thickness conditions,and the influence mechanism and sensitivity of various parameters on the surface subsidence velocity were obtained.The results indicate that:the surface subsidence velocity increases with the increase of mining speed,mining height and mining width,but decreases with the increase of foundation rock thickness and loose layer thickness;the maximum surface subsidence velocity increases linearly with the increase of mining speed,mining height and mining width,and decreases linearly with the increase of loose layer thickness,which decreases in power function with the thickness of bedrock layer;the sensitivity of each influencing factor to the maximum surface subsidence velocity is mining width,bedrock layer thickness,loose layer thickness,mining speed and mining height in descending order.