岩溶区某拟建隧道的地下水灾害评价

Groundwater Disaster Assessment of a Proposed Tunnel in Karst Region

根据重庆市某典型岩溶区隧道工程的水文地质调查结果,对区域内岩溶发育特征及其影响因素、地下水灾害评价等进行探讨。研究表明,该区域地质构造、水动力模式、地层岩性和地形地貌特征对岩溶发育有重要影响,造成该区域发育大量岩溶洼地、落水洞、溶洞和地下暗河等岩溶地貌。通过大气降水入渗法和地下径流模数法进行隧道用水量计算发现,前者得到隧道多年平均降雨量的日涌水量为16069.52m^3/d,为后者的2.7倍。针对隧道开挖的环境地质问题,如隧道开挖形成较大的集水廊道可能造成隧道两侧较大范围内水源枯竭、岩溶塌陷,隧道涌水及施工过程中的废水、废渣外排污染等问题进行分析。研究可为相似工程提供经验参考。

Based on the hydrogeological survey of tunnel engineering in a typical karst area of Chongqing,the characteristics of karst development and its influencing factors,and the evaluation of groundwater disasters are discussed. The study shows that the geological structure,hydrodynamic model,stratigraphic lithology and topographic features of the region have an important impact on the development of karst,resulting in a large number of karst depressions,falling water caves,karst caves and underground rivers.Through the calculation of tunnel water consumption by the infiltration method of atmospheric precipitation and the modulus method of underground runoff,it is found that the daily inflow of annual average rainfall of the former is 16069.52 m^3/d,which is 2.7 times of that of the latter.Aiming at the environmental geological problems of tunnel excavation,such as the formation of large catchment corridor in tunnel excavation,which may cause water source exhaustion,karst collapse,tunnel water gushing,waste water and waste residue pollution in the construction process,etc.,are analyzed.The research can provide experience reference for similar projects.