Field Investigation of Influences of Load on Pile Top on Negative Skin Friction Behaviors

Abstract

In order to study influences of applied load on pile top on the negative skin friction behaviors of piles, field investigations of negative skin friction behaviors of three identical piles with different loads on pile top are made in the same site. Test results show that applied load on pile top affects negative skin friction behaviors evidently. Additional settlement of pile induced by negative skin friction becomes larger, negative skin friction induced by the settlement of soil surrounding the pile becomes smaller with the increase of load on pile top. Dragload induced by negative skin friction decreases and position of neutral point in pile moves up while applied load on pile top increases. While there is no applied load on pile top, additional settlement induced by negative skin friction is minimum, dragload induced by negative skin friction is maximum and the neutral point is the farthest from the top of piles. The field investigation results may be useful to the further research for negative skin friction behaviors of pile.