Response of shaft friction along existing piles to deep excavation

Excavation following the installation of pile may significantly affect the original behavior of installed piles. To better understand the shaft friction response of existing piles during deep excavation, the principle of pile loading transfer was discussed in this study. Based on the concept of interface normal stress and interface relative displacement, a 5-segment distribution pattern of pile shaft friction was proposed. The varying law and practical calculation model of shaft friction subject to deep excavation was also proposed through numerical analysis. Its feasibility was verified against case histories and this could provide possible reference to pile design incorporating excavation effect.