LAND SUBSIDENCE OF COAL MINE AREAS IN HUANGHE-HUAIHE PLAIN, EASTERN CHINA

摘要

It was proved by observation that expanding / compressing of water- bearing unconsolidated sediments of Cenozoic beds in coal mine area in Huanghe- Huaihe Plain varies with depth and season, and the chief dewatering- compression segment is in lower part of the sediments induced by groundwater drainage from mine pits. The relationship between strata compression and breakage of mine shafts is analyzed. Numerical calculation of viscosity mechanics attests that a big vertical stress is added to shaft walls around level of interface between soft soil strata and hard bedrocks due to dewatering- compression within bottom Cenozoic strata, and it can lead shaft failure as it exceeds the intensity limit of shaft materials.