Physical modelling of bending moments in single piles under combined loads in layered soil

Abstract

Pile foundations are very important elements in the design of railways and bridges. In many projects, piles are under the combination of vertical and horizontal loads. In this regard, the maximum moment which is applied to the piles is a key factor for designers. Therefore, in this study, experimental investigations on loaded single piles in sandy soils with different energies in various conditions of loading and relative densities were performed. Nine physical modeling tests were created to evaluate the load-deflection response, bending moment and strain along with the driven aluminum model pile. The single piles were subjected under both horizontal and combination of horizontal and vertical loads. The dimensions of soil tank and model pile were designed by considering chamber size effects and internal scale effects. The results showed a significant difference in magnitude and shapes of bending when the mole pile was subjected to combined loads with a relative density of 30% (loose) and 75% (dense). Additionally, the combined load test results demonstrated that the bending moments and lateral deflection of the pile head increase substantially in the presence of vertical loads. Finally, two computational models were proposed to estimate the maximum moment on the piles.