Analysis of Under-Reamed Piles Subjected To Different Types of Load in Clayey Soil

Under-reamed piles with one or more bulbs have been widely used in almost all types of soil to support a range of structures. in some cases, in addition to vertical compressive or uplift loads, piles must withstand a considerable lateral load. a 3-d finite element study using abaqus software was conducted to examine the behavior of under-reamed piles in clay soil under pure lateral, pure uplift, and combined uplift and lateral loads. in this study, pile (l/d) ratios of 11.66, 15, 20, and 25 were considered by adjusting the pile length to simulate the behavior of rigid and flexible piles. the piles were modeled as a linear elastic material, and the soil behavior was simulated using the drucker-prager constitutive model. the findings show that the lateral resistance of piles with (l/d) ratios of 11.66 and 15 increased slightly when under-reamed piles were used. however, no change in lateral resistance was observed for under-reamed piles with (l/d) ratios of 20 and 25 compared with straight piles. the uplift capacity of under-reamed piles was significantly greater than that of a straight pile. the lateral capacity was marginally influenced by the prior uplift loading, such that it decreased for a rigid under-reamed pile, and increased for a flexible under-reamed pile