超大面积港池深基坑截渗与降水分析  

Seepage and precipitation analysis of untra-large-area basin deep foundation pit

作　　者：李松斌[1] 谢小明[1] 肖莹萍[2] 

机构地区：[1]中交四航局第二工程有限公司,广东广州510300 [2]华南理工大学,广东广州510640

出　　处：《水运工程》2015年第10期182-187,共6页Port & Waterway Engineering

摘　　要：挖入式港池基坑往往具有面积大、开挖深度大、紧邻河海等特点,因此港池基坑的止降水难度大、风险高。卡塔尔多哈新港港池基坑为石灰岩上覆沉积砂层的双层强透水地层中的超大深基坑。本工程地下水控制设计采用嵌岩地下连续墙和深井降水的组合方法。通过对地下连续墙内外水位实测资料的分析可知,其隔渗效果较差。地下连续墙在该工程中的功能仅体现在改变了其周边局部区域的渗流场。利用地下水模拟系统软件包GMS中的MODFLOW模块进行港池基坑局部片区的基坑降水计算,通过改变深井降水的各参数(包括抽水井数量、抽水量和井距)对深井降水进行优化设计,为类似工程的深基坑降水设计提供借鉴。Foundation pits of excavated-in basin often has large area and large dredging depth, and they are often close to rivers and sea, so the precipitation of foundation pits of excavated-in basin is difficult and faces high risks. A foundation pit of excavated-in basin in Qatar Doha is super large and deep. Geological conditions of the project site are double strong permeable stratum of sedimentary sand overlying limestone. Groundwater control design of the project uses diaphragram retaining walls and deep wells. Based on the analysis of water level inside and outside the underground continuous wall, seepage flow effects of the underground continuous wall is poorer. Functions of underground continuous walls in this project only embodied in the change of seepage of some areas surrounding the underground continuous wall. Based on MODFLOW module of GMS, we calculate foundation pit precipitation of basin local area. By changing the parameters of deep well precipitation （ including the pumping well number, water output and well spacing, and optimize the design of deep wells precipitation, which can be helpful to the design of foundation pit dewatering for similar projects.

关 键 词：挖入式港池 深基坑 降水 地下连续墙 深井 

分 类 号：TU753[建筑科学—建筑技术科学]