Disaster analysis and countermeasures of land subsidence caused by coal cutting in China

In recent years, many coal-producing countries have paid great attention to the land subsidence caused by coal cutting. In China, because of the dense population in coalfield areas, the land subsidence hazard is more serious. After a brief analysis on the mechanism of land subsidence, this paper gives a comprehensive and systematical account on all kinds of hazards caused by the land subsidence in China. The study shows that land subsidence has endangered land, buildings, traffic and communication lines, dykes and dams. It also causes damage to ecological and social environment. In order to lessen the hazard of land subsidence, preventive measures should be taken to reduce the collapse amount, such as extraction with stowing, banded mining system, succession and coordination mining system, or high-pressure mudflow between rock strata. Measures of reinforcing or moving certain buildings should also be taken to reduce the destructive degree. In order to harness the subsidence land and bring them under control for farming, measures should be taken such as filling with spoil or fine breeze, excavating the deeper and covering the shallower land.