3D numerical investigation of the reduction in load capacity of piles embedded in collapsible soil

Most regions of Brazil feature soils with a meta-stable structure, resulting from weathering processes and influenced by the unsaturated condition of the surface soil. Increased moisture has a significant impact on soil structure, potentially leading to differential settlements that can cause damage to buildings situated on these grounds. This study aims to investigate the effect of soil inundation around piles on the load capacity of the pile-soil system. Static load tests with slow loading were conducted at the UNICRUZ Experimental Field, both with dry and inundated soil, on conventional piles and those with tip reinforcement (with 30 cm of compacted gravel). The results of these tests were used to validate numerical simulations performed in the Midas software. The simulations revealed a significant reduction in the support capacity of the pile-soil system after inundation, especially in the lateral resistance of the piles. It is concluded that the experimental and numerical procedures of this study are useful for the design of foundations in soils susceptible to collapse.