Centrifuge modeling of the pile foundation reinforcement on slopes subjected to uneven settlement

Abstract

Uneven settlement often induces the slope instability problem and the consequent inclination in upper structure. The response of the slopes with shallow foundation, vertical pile foundation, and inclined pile foundation subjected to uneven settlement are investigated using centrifuge model tests. The uneven settlement induces a significant progressive failure in the slopes with shallow and vertical pile foundation. By contrast, the slope with inclined foundation maintains good stability. Full displacement field of the slope-foundation system is obtained by employing an image-based measurement method. The inclined pile foundation exhibits much smaller top center displacement and inclination angle than the shallow foundation and vertical pile foundation. The slope failure mechanism is revealed through an integrated analysis of deformation localization and local failure. On that basis, the reinforcement mechanism of the inclined pile foundation is illustrated by the weakening of the deformation localization in the slope and hence preventing the local failure. The corresponding reinforcement effect on the slope is further presented in terms of the reduction of deformation and the restriction to uneven settlement influenced area. Therefore, the inclined pile foundation with an angle of 60° is confirmed to be effective in resisting the uneven settlement and reducing the slope deformation within acceptable foundation inclination.