Publication Abstract

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

9 Testing and Analysis of Preliminary Test Piles in Very Weak Chalk
S.P. Corbet & D.S. Culley; G. Maunsell & Partners, Consulting Engineers, UK D.E. Sherwood & J.E.M. Cockcroft Bachy Group, UK

The design construction and testing of three 40m long 1.2m diameter instrumented bored piles at the site of the River Yare Viaduct on the A47, near Norwich, Norfolk U.K., is described. The analysis of the results and the changes made to the contract design are discussed. The tests were intended to provide site specific parameters for the design of working piles. The unlined bores of the piles in the chalk were supported with three different fluids, water, bentonite suspension and a polymer drilling fluid. The differences between the load carrying capacities of the three piles and construction techniques is examined. The implications of the preliminary trials on the final pile lengths and layout is discussed. The relationship between the development unit shaft friction and static cone test local friction is examined and a relationship between these parameters is presented.

 article #450; publication #37 (IC-1991-IT)