Estimation of ultimate bearing capacity for bulging failure of granular compaction group piles

Abstract

In the present study, a series of full-scale load tests is performed at the construction site of the Western Sea Express Highway in Korea, and the testing results are described. In the present study, a procedure to predict the depth from the ground surface to the center of bulging failure zone in each of the both square and triangular granular group piles under a rigid mat foundation is also proposed. This analytical procedure is established based on the conical modeling of bulging failure shape and the replacement ratio of soft foundation soils. Further proposed is an analytical procedure to estimate the ultimate cylindrical pressure in the reinforced area with granular piles and the ultimate bearing capacity of each of granular pile in-group. This analytical procedure is also established base on the pre-determined depth to the zone of bulging failure and an iterative solution technique. Finally the analytical procedures proposed in this study are verified by analyzing the results of 3D finite element analyses, and the predictions of ultimate bearing capacity of granular piles are compared with the results obtained from the tests and 3D finite element analyses.