Methods of resisting hydrostatic uplift in substructures

Abstract

Many underground structures are constructed for use as car parks and shops in basements of buildings and as mass rapid transit stations, depressed roadways and civil defense shelters in cities located in coastal areas where the ground is level and the elevations are low, with an attendant high groundwater table. This paper discusses the various methods of resisting hydrostatic uplift. These include the use of tension piles and the installation of a water pressure relief system under the base slab of the basement. A case history in Singapore employing a pressure relief system below a three-level basement is presented.