采煤活动对唐山城市建设场地稳定性的影响分析

Analysis on the impact of coal mining on the stability of construction area in Tanshan City

通过InSAR地表变形监测技术和数学模型理论计算,采空塌后期场区地基土的稳定性主要取决于采空区顶部的土体而不是岩体。城市规划区内局部有5层可采煤层,尤其是-200m以下的煤层停采在20世纪70年代以前,已完全塌落、压密、再造。而塌后期的土体底部粘土隔水层被拉裂,在双层水位作用下发生潜蚀形成土洞造成地面不均匀沉陷,影响城市建设场地的稳定性。

By InSAR surface deformation monitoring technology and mathematical model of theoretical calculation,it was found that the stability of ground depended largely on the soil rather than rock of the mined-out area top at the mined-subside later stage.There were five layers of local coal seam at the Urban planning area.Mining the coal seam of below-200m had stopped before 1970’s,thus the seam has been completely,recycled and collapsed.The impermeable clay layer at the bottom of the soil pulled cracking at the mined-subside later stage.It came into being latency-erosion action and soil caves,introducing an uneven land subsidence on the effect of double groundwater levels.The uneven land subsidence has affected the stability of urban construction area in Tangshan.