湖南长沙县江背镇地面塌陷发育特征和成因机理分析

Analysis on the Distribution and Formation Mechanism of Ground Collapse in Jiangbei Town of Changsha County in Hu'nan Province

摘要:

地面塌陷地质灾害严重制约着城市的发展，长沙县江背镇河田一带有着悠久的采石灰岩矿的历史，形成了大量的采坑和采空区，加之区内浅层覆盖型岩溶发育，采空塌陷和岩溶塌陷对周边居民生产生活有极大的影响。本文在系统收集和研究前期资料的基础上，通过综合的勘查手段查明了本区地面塌陷发育特征并进行成因机理分析：采空塌陷具有三阶段变形的特点，主要受地层岩性、地质构造、地下水、采矿活动控制；岩溶塌陷主要由潜蚀效应、垂直渗压—自重效应引起，受地层岩性、岩溶发育情况、上覆土层“二元结构”、地下水等因素控制。两种地面塌陷均是自然与人为影响因素相互作用、相互影响、共同叠加而形成的。现状地面变形处于基本稳定状态但仍有继续发展的可能，据此提出了相关的防治建议。

Abstract:

Geological disasters of ground collapse severely restricts the development of cities. The area of Hetian in Jiangbei town in Changsha county has a long history of limestone mining. A large number of mining pits and goafs have been formed. Shallow covering karst are developed well in this area. The ground collapse of goaf and karst has a great impact on the production and life of surrounding residents. Based on systematic collection and research of previous data, distribution of ground collapse in this area has been identified by using comprehensive investigation methods, and the formation mechanism has been analyzed. The collapse of mining subsidence has the characteristic of three-stage deformation. It is mainly controlled by geological lithology, geological structure, groundwater and mining activities. Karst collapse is mainly caused by subsurface erosion effect, vertical seepage pressure self weight effect. It is controlled by geological lithology, karst development, the "binary structure" of overlying soil layers and groundwater. Both types of ground subsidence are formed by the interaction, mutual influence, and superposition of natural and human factors. The current ground deformation is in a basically stable state. But there is still a possibility of further development. Based on this, relevant prevention and control suggestions have been proposed.