Investigation of mining engineering conducted in Tongting Mine,Taoyuang Mine and Qidong Mine in Huaibei area justifies the fo...

• 通过淮北地区童亭、桃园、祁东等矿井开采实践,认为巨厚松散层下采煤煤岩柱的留设原则为:初期以防水为主,后期以防砂为主。