Recommendations : load-transfer criteria for piles in clay

Abstract : This report presents a comprehensive evaluation of load-transfer criteria for analysis of axially loaded piles in clay. The US Army Corps of Engineers installs thousands of piles each year in the construction of navigational and flood control structures. So that these structures will perform satisfactorily, not only must the capacity of the pile foundations be adequately determined but the load-deformation behavior of the foundation must also be predicted to allow an analysis of the structure for stresses and deformations. Various predictive methods for computing side resistance capacity and shear transfer versus vertical pile movement, f-z curves for clay are presented. Parametric studies were conducted to determine the method that could best represent pile behavior. Instrumented pile loads were used to evaluate the performance of the methods under actual field conditions. Based on these investigations, procedures for determining side resistance and shear transfer versus vertical pile movement are recommended. Keywords: Pile structures; Structural foundations; Axial loads.