Research Article
S.B. AKPILA
Abstract
The performance of both square and circular foundation on clay in the offshore Niger Delta has been attempted based on wave load simulation. Horizontal forces were evaluated from the impact of varying wave heights on circular piles while the empirical methods of Skempton, Brinch Hansen and Vesic were used to evaluate vertical loads. Sliding failure of square footing begins when the ratio of vertical load to area and undrained shear strength,V/Asu, assumes negative values (i.e. at H/Asu > 3.427) while for circular footing, it occurs when mean value of the ratio of horizontal force to footing area and undrained shear strength, H/Asu, is greater than 0.0816. For square footing stability against sliding , the vertical load should be at least twice the anticipated horizontal load,while for circular footing, the vertical load should be at least 75 times the horizontal load anticipated when the ratio of foundation depth to breadth is lesser than one, Df /B<1.0, and 70 times for Df /B>1.0. For square foundation with Df /B>1.0, higher horizontal force of about 10.5 times greater than those for Df /B<1.0 are required to initiate sliding.