与地下水作用有关的地质灾害

人类发展演化过程中,经历了各种各样地质作用所造成的灾害,其中大部分地质灾害的形成都有地下水的参与。据大量事实统计,地下水与岩土体互相作用所造成的地质灾害具有类型的多样性、机理的复杂性、分布的广泛性、灾害的严重性和可控性等特征。同时,目前在生产和科研实践中对地下水作用致灾的重要性认识及勘察研究投入不够,在地质灾害评价预测中对地下水作用的定性定量分析是个薄弱环节。因此,必须强调和加强地下水与岩土体互相作用效应的勘察研究。地下水与岩土体间复杂的物理化学作用必然引起二者物质成分、性质和状态的变化。其中尤以地下水位升降和水力坡度的变化影响最大,从地下水作用致灾机理看,有静水推力、有效应力变化、渗透压力增大、水力楔入、冰劈、水的加载、水化、水击、土体冻融、淋溶和沉淀等作用。文中以渗透变形灾害为例分析了地下水与土体的相互作用效应。在此基础上提出勘察工作应以查明地下水的埋深和补给来源,查明沿渗流方向的地层岩性、成因、物质成分、厚度、空间分布和透水性为主。指出防治对策应针对灾害类型、机理、地质环境、保护目标不同,既以治水为主,又要区别对待,与环境保护同步考虑。

Geological hazard related to underground water

During the history of human development, we have suffered so many kinds of hazard caused by geological process, and most of the hazard have something to do with the interaction of underground water. According to various facts, geological hazard caused by the coupled interactions between underground water and rock (or soil) have the following features: they are various in type, complex in mechanism, broad in distribution, serious and can be controlled. While, at the same time, the importance of cognition and devotion in investigation or researching are not adequate enough, and the quantitative analysis of the interaction of underground water is still weak now. So the reconnaissance and investigation on coupled interaction between groundwater and rock must be enhanced and emphasized. The complex physical or chemical interactions between groundwater and rock (or soil) will result in the changing of substantial component, character and state. In which, the interaction of the rising and falling of underground water is predominate. From the mechanism of the hazard resulted from groundwater, the interactions can be summarized as static water pressure, effective stress changing, penetration pressure, hydraulic wedging, hydraulic splitting, hydraulic loading, hydrolyzing, hydraulic impacting, soil's expanding and shrinking, soil's freezing and melting, and so on. Based on the example of penetration deforming hazard, this thesis analyzed the interaction of groundwater and rock, and at same time put forward the viewpoint that the following items should be cleared in investigation: the depth and compensation source of underground water, the stratum, lithology, causing reason, components, depth, distribution and penetrability along the penetrative direction. This thesis also pointed out that the treatment should correspond to the hazard type, mechanism, geological environment, prevention target, and so on. We should not only based on the primary target of treat underground water, but also correspond to the protecting of the environment.