Research on Roadway Surrounding Rock Classification Method at Strongly Weathered Zone

摘要

The mining area at mining superior limit approaches outcrop adjacency of coal seam. Its coal or rock mass situates on strongly weathered zone and oxidized zone. The weathered fissure of coal or rock mass is increasing. And the bulky degree and fragmentation degree of surrounding rock are relative bigger under all kinds of external force acting, such as digging and mining , etc.., which makes the strength of coal or rock mass much lower than that of the deep-seated unweathered coal or rock mass . During the digging and upkeep work, the roadway which situates at strongly weathered zone easily generates series of problems, such as surrounding rock load-bearing descending and ground behaviour intensifying, etc...In order to solve these engineering problems, the surrounding rock at strongly weathered zone need be properly classified, which can scientifically determine roadway support pattern and support parameters. However, at present, the conventional surrounding rock classification methods in coal mine can't well classify surrounding rock of strongly weathered zone. So, for the surrounding rock characteristics at strongly weathered zone, this article detailedly analyses the major factors affecting roadway surrounding rock type and proposes the surrounding rock classification method which suits strongly weathered zone roadway. This method has been applied surrounding rock classification in entry of Datun Mining Group, resulting in good social and economic benefit.