Study on strip mining size under thick alluvium and thin bedrock

On the basis of the observation data of strip mining under structure and combining with numerical simulation,the surface subsidence rule of different mining and reservation width in strip mining under thick alluvium and thin bedrock were analyzed.The study shows that the calculated subsidence coefficient according to common strip mining is smaller than the actual value;the subsidence increases along with bedrock thinning with same mining width,and it is small when mining width is small with same bedrock;the subsidence increases more obviously with mining width increasing with thinner bedrock.In order to ensure the significance to control subsidence,while designing the mining and reservation width,not only design principle but also bedrock thickness should be considered,which can make the supporting terrane exist in bedrock.