ABSTRACT

With ageing, older jacket platforms may have less than perfect pile cap conditions. A centrifuge model study has been conducted to evaluate the spudcan-pile interaction under free and fixed pile head conditions during spudcan penetration in soft clay. Owing to the weakened restraint at the pile head, the pile lateral deflection increases significantly whereas the bending moment reduces by a large extent. The bending pattern of a free-head pile is different from that of a fixed-head pile, and the pile bends towards the spudcan at shallow spudcan penetration depths and subsequently bends away from the spudcan when the spudcan penetrates further. An analytical approach is then conducted to evaluate the pile responses with partially fixed pile cap condition.