Investigating the Behavior of Foundation Piles Experiencing Downdrag

Abstract

In foundation piles, the friction between the soil and the pile in most cases resists the downward weight of the building until equilibrium is achieved. However, in many cases a surcharge load is placed under the structure after initial loading, causing the soil to compress and cause a downward force on the pile which causes further settling of the structure. In this project, the behavior of friction forces under reversal of direction was studied in a laboratory environment for many different materials. An existing hyperbolic model was modified to fit the data, and a linear relationship was found between the roughness of a material and the behavior of the friction force development.