Estimation of Friction Capacity of Driven Piles in Sand: Effect of Sand Dilation

This paper is dedicated to investigate the effect of sand dilation during pile axial loading on ultimate shaft capacity of driven piles in sand based on a database comprising of 37 well-documented full-scale pullout pile load tests collected from literatures. The results indicated that the contribution of sand dilation during pile axial loading to the measured shaft capacity is significant for piles with diameter less than 0.40m in medium dense and dense sand especially at low stress level. In some cases, sand dilation may contribute to as high as 45% of the measured shaft capacity. For piles with diameter greater than 0.60m, the contribution of sand dilation to the measured shaft capacity is small and generally less than 10% especially at high stress level. A design methodology for tension piles in sand which incorporates the effect of sand dilation is proposed in this study. The validity of the proposed method was verified by comparing prediction with measurement made on a well-documented field case from literature. The comparison indicated that the proposed approach gives reasonable prediction and thus can be used to predict shaft capacity of driven piles in sand.Presented at the Conference CESARE'22 3rd Coordinating Engineering for Sustainability And Resilience, May 6th – May 9th, 2022, Irbid, Jordan, ISSN:2788-620