南京长江第五大桥夹江隧道明挖段基坑深降水设计

Deep Foundation Pit Dewatering Design in the Excavation Section of Jiajiang Tunnel at Nanjing Yangtze River Bridge No.5

以南京长江第五大桥夹江隧道明挖段基坑降水为工程背景,针对南京长江漫滩地区上部粘性土层为软土层与硬土成互层结构,在软土层中夹有粉细砂层透镜体,下部砂层的厚度较大(3~40m),为承压含水层等特点,采用Visual MODFLOW软件建立多层含水层地下水模型,提出了合理的深基坑降水方案。

The engineering background is the excavation section of the Jiajiang tunnel in the Nanjing Yangtze River Bridge No.5. The upper clay soil layer in the Yangtze River floodplain area in Nanjing is an interbedded layer of soft soil and hard soil, with fine powder in the soft soil layer. Sand lens body, the thickness of the lower sand layer（3 ~ 40 m）, is a confined aquifer and other characteristics, the use of Visual MODFLOW software to establish a multi-layer aquifer groundwater model, put forward a reasonable deep-pit dewatering program.