Publication Abstract

Proceedings - Fourth International Conference - Piling and Deep Foundations, 1991, Stresa, Italy, (DFI)

Diaphragm Walls, Load Bearing Piles and Piled Soil Reinforcement for a Deep Top Down Basement Construction
J.R. Hollingdworth; Cementation Piling & Foundations Ltd., UK

The Basement, designed and constructed at Aldersgate Street, is reputedly the deepest construction in the City of London. The basement in 25m deep and is for seven levels of car parking. It is supported by a 1m thick diaphragm wall and 2.4m diameter piles with toe levels respectively 30m and 53m below installation level. With such a deep basement in clay subsoil, a particularly challenging and innovative design was required to cope with the ground heave and strength loss in the front of the wall. The construction of this major civil engineering scheme was complicated by very limited access, by structures abutting on three sides of the site, and by an adjacent residential center. The working hours were legally limited to just ten hours per day. The details of the design and in service performance of the foundation works has been described by Fernie at al (1991). This paper describes the methods and techniques used to construct these works.

 article #460; publication #37 (IC-1991-IT)