北京西山地面塌陷的形成因素浅析

ANALYSIS OF CONTRIBUTING FACTOR TO SURFACE COLLAPSE IN XISHAN REGION, BEIJING

地下采矿是地面塌陷先决条件．自然重力及其他外界触发因素是其发展动因。地面塌陷受覆岩时代及岩性、采空区尺寸大小、煤层倾角、煤层厚度及开采深度、重复采动、水文条件变化、地形地势和松散盖层的影响。

In Xishan region of Beijing,the main occurrences of surface deformation and collapse,resulted fom the coal mining activities, are surfacial moving basins,collapse pits,ground fractures,mountain landslides and the uneven subsidence of ground surface.The major calamities that resulted from them have broad effects. Which strengthened the worsening of the geological environments of hilly region, primarilly analyzed the major factors that may form surfacial collapses in this region,the present authors concluded that the major factors to form collapses and affect the occurrence morphology of the collapses are:variation of the strata dip angles,the size of miningout area and the vertical depth from ground surface, the productive thickness of the coalbeds,the lithological features of coalbed roof,the influence of repeatedly mining,the thickness and lithology of surf actal soil,the influence of regional hydrogeology condition and the relief.