Experimental investigation on single model pile in sloping ground under lateral load

Abstract

Piles have been extensively used for supporting axial loads and lateral loads for variety of structures including high rise buildings, transmission towers, power stations, offshore structures and highway and railway structures. Many transmission towers, high rise buildings and highway and railway bridges are constructed near steep slopes which are supported by pile foundations. These structures may be subjected to large lateral loads such as strong winds or earthquakes. When piles are constructed in sloping ground, the behaviour of piles under lateral load is different from piles in horizontal ground. The present investigation is to study the behaviour of piles on sloping ground under lateral loads. A series of laboratory model test had been carried out on the instrumented pile on horizontal ground, 1V: 2H slope and 1V: 1.5H slope with the relative density of sand at 30%, 45% and 70% and varying embedment length to diameter ratio of 25, 30, and 35. From the experimental results, the behaviour of the pile was studied by its lateral load - pile head displacement response and bending moment profile along the pile shaft. From the load-deflection and bending moment behaviour, a correction factor for the lateral load capacity and the maximum bending moment for the sloping ground was obtained. An equation for the depth of fixity for the cohesionless soil including the effect of ground surface, relative density and embedment length was obtained. This experimental study is also used to develop a graphical non-dimensional relationship, between the lateral load and maximum bending moment in pile.