Design of socketed piles in weak rock : Williams, A F; Johnston, I W; Donald, I B Proc International Conference on Structural Foundations on Rock, Sydney, 7–9 May 1980, P327–347. Publ Rotterdam: A A Balkema, 1980

Abstract

The design method described in this paper was developed for high load capacity foundations in the city of Melbourne, where the bedrock is silurian mudstone, henceforth called Melbourne mudstone, occurring at depths varying from zero to at least 50 m. On the basis of a wide range of theoretical, laboratory and field investigations, a method for the design of piles socketed into weak rock has been proposed. The method presented differs from existing methods in that it satisfies both allowable settlement and strength criteria, and that it accommodates the general non linear load deformation characteristics observed for such piles. The proposed method allows for the design of socketed piles to support load by side resistance or base resistance only, or, by consideration of the contribution of the two components through relative interaction and mobilization, by both side and base resistance acting together. The application of the design method is discussed on the basis of rock parameters and construction practice, and examples are given. While the proposed method has been developed for piles socketed into the Melbourne mudstone, it is considered that the concepts presented may also apply to a wide range of other rock types.