This project includes experimental and numerical studies to investigate and assess the impact of vertical loads on a laterally loaded drilled shaft under various conditions. The experimental study includes lab testing and lab-scale load test to examine a drilled shaft subjected to vertical and lateral loads at a reduced scale. With the data obtained from the lab-scale testing, a numerical model was calibrated, which was used to perform a parametric study to scrutinize the effect of many possible factors such as soil stiffness, soil friction angle, and drilled shaft geometry. With all the factors considered in this study, the vertical load does not show significant impact on the lateral deflection of a drilled shaft unless the lateral force is very high and induces a very large deflection. Based on the outcome of this study, it can be concluded that interaction between vertical and lateral loads might be insignificant when the lateral deflection is no greater than 25 mm (i.e., one inch).

Tran-SET Project No. 18GTTSA02