南京典型段地铁工程对地下水流动态的影响

本文以“南京典型段地铁工程”为研究对象,利用FEFLOW数值模拟软件建立非稳定流数值模型,预测了地铁开挖涌水量大小以及研究了在施工期、运营期和服务期满后区域地下水流场动态变化;分析了地铁建设对仙鹤门水源地流场的影响以及可能引发的环境水文地质问题。结果表明：由于地铁施工开挖导致的隧道涌水以及需要疏干降水,在施工站点和区间隧道地下水位大幅度下降,运营期和服务期满后地下水流场逐渐恢复到初始状态;地铁工程对仙鹤门水源地影响较大的区段主要是龙王山段,其他区段对水源地影响轻微。而研究区内桦墅站至龙王山区段灰岩埋藏浅,岩溶发育强烈,地铁工程可能导致局部地区径流条件发生变化,诱发岩溶地面塌陷灾害。

Research on the influence of typical subway project in nanjing on underground flow dynamics

This paper takes "nanjing typical section subway project" as the research object and uses FEFLOW numerical simulation software to establish unsteady flow numerical model. The magnitude of excavation inflow of subway is forecasted, and the dynamic changes of regional groundwater flow field after construction period, operation period and service expiration are studied and analyzes the influence of subway construction on the flow field of xianhemen water source and the possible environmental hydrogeological problems. The results show that the underground water level of the tunnel in the construction site and the tunnel in the section decreases greatly due to the water gushing and the need to drain the precipitation caused by the subway excavation, and the underground water flow field gradually returns to the initial state after the operation period and service expiration. The longwangshan section is the main section where the subway project has a great impact on xianhemen water source, while the other sections have a slight impact on the water source. However, the limestone in the research area from huashu station to longwang mountain area is buried shallow and karst is developed strongly. Therefore, subway engineering may lead to changes in runoff conditions in local areas and induce karst ground collapse disaster.