Model study on the performance of single-finned piles in clay under lateral load

Abstract

Generally, foundations of many structures, such as transmission towers, bridge abutments, ocean engineering structures, marine dolphins, dock-fendering systems, and moorings are subjected to different modes of lateral loading. This research aims to study an alternative and novel technique to improve the lateral pile capacity in clay using fins at the top of piles. Laboratory small-scale model tests were carried out to study the behavior of laterally loaded finned piles installed in clay soil for different undrained shear strengths (Cu = 11 and 15 kPa). The effects of different factors, such as pile type, stiffness, geometric dimensions, and shapes of fins, were studied. Moreover, the effects of the fin number and inclination angle were also investigated. Results emphasized that there is an increase in the lateral pile resistance against the lateral load after placing fins at the top of the pile head. It has been found that the optimum length of the adopted fins should equal 0.4 of the pile embedded length and the fin width should equal the pile diameter. The existence of fins improved the behavior of finned piles by 1.67 and 1.55 for piles of L/D = 10 in the case ofCu = 11 and 15 kPa, respectively, compared to regular normal piles in the same condition. Also, the improvement in L/D = 22 piles due to fins reached to 1.29 and 1.35 for the case of Cu = 11 and 15 kPa, respectively.