Effect of installation mode, pile shape and cycling on the ageing of shaft friction of mild steel piles

Abstract

Significant uncertainty exists regarding the effect of axial cyclic loading and installation technique on the ageing characteristics of displacement piles. To address this, the current study investigates the influence of installation method, pile shape and cyclic loading on the ageing of shaft friction of steel piles in sand. The research is based on field testing that indicated a significant increase in shaft capacity with time for all circular piles. The mode of installation had a notable effect on short-term capacity, although long-term capacity remained largely unaffected. The results also show that one-way tension cycling of piles within the stable zone of the cyclic interaction diagram did not lead to a significant reduction in the growth of shaft friction with time, as observed in first-time tests. Show more