Laboratory Investigation of Load Incremental Effect on the Deformation of Clay Under Axially Loaded Modeled Circular Piles

Abstract

This paper presents the results of recent experimental investigation of load incremental effect on the deformation of clay under axially loaded modeled wooden circular piles in clay. The modeled piles consist of 20 mm diameter, 200 mm length, made up of single pile, 4 No pile group of 2x2 with centre to centre a = 4d, and 9 No pile group of 3x3 with centre to centre a = 3d, were driven into clearly marked layered clay soils differentiated by w = 20%, gamma = 17 kN/m(3) for the weak; w = 10%, gamma = 19 kN/m(3) for the strong) while the third class of reinforced weak layer had hollow reinforcing bars placed in it. The tests were conducted in a specially designed testing equipment/tank. The modeled piles were subjected to axial compressive loads at incremental rate of 0.01, 0.05, 0.1 and 1mm/min respectively. A linear relationship was observed between the load incremental rate and pile axial capacity and pile displacement, which were also visible from the increase in the radius of curvature of the displaced/deformed soil from the pile centre-line.