天津宝坻县隐伏岩溶区地下水开发与地裂缝成生关系研究

在调查分析地裂缝时空分布特征的基础上,研究地裂活动与区内水文地质条件、地下水开采过程的关系,认为过量开采奥灰水是产生地裂缝的主导因素。随着水位下降,盖层介质固结压密作用是导致地面压缩变形乃至地裂缝发生的直接原因。地下水系统结构特征以及固结压密作用的物质基础———松散盖层的厚度、岩性,是构成地面不均匀沉降的充要条件。当这种不均匀变形程度足以使土体连续性破坏时,则地裂缝便在沉降区应力集中的部位发生。

Relationship between karst water exploitation and ground fissure in the unconsolidated sediment area of Baodi County, Tianjin

In this paper,the authors discussed on the relationship between ground fissure development with hydro-geological environment and groundwater exploitation,based on the survey of time-spatial occurrence of the ground fissures.Excessive exploitation of groundwater in Ordovician limestone is the key reason for the formation of ground fissures.With the groundwater table falls,the material in overlying strata will be consolidated,which is the direct reason for the ground compactness and the occurrence of fissures.The structure of groundwater system and the properties of the unconsolidated coverage(the thickness and the lithological characteristics) constitute the necessary and sufficient conditions for inhomogeneous subsidence.When the deformation caused by the inhomogeneous subsidence accumulates to the critical state of the soil,ground fissures will occur in the stress concentration positions.