Centrifuge model study of the response of spudcan with lattice leg to rocking

Abstract

This paper describes a centrifuge model study for examining the influence of lattice leg on the response of a spudcan in clay to combined cyclic loading. The loading apparatus, which superimposes a cyclic lateral load onto a constant axial load on a spudcan foundation is first described. Cyclic-induced settlement of the spudcan is examined using experimental data. The findings showed that the spudcans with lattice legs undergo smaller settlement compared to the ones without lattice, indicating that the lattice helps to reduce the total settlement. Comparison is also made between spudcans which have just been installed and those which have been installed for a long time, the intent being to investigate the influence of installation-induced excess pore pressures on the rocking and settlement of the spudcan. The data shows that installation-induced excess pore pressure influences spudcan behaviour by decreasing the stiffness and strength of the soil around the spudcan. In addition to the larger rotation and settlement under the same moment, spudcan foundation which is subjected to rocking just after installation, hereafter designed "short-term", also generates larger excess pore pressure than one in which installation-induced excess pore pressure has dissipated, hereafter designed "long-term". The "short-term" settlement of spudcans is also larger than the "long-term" settlement and is subjected more "non-linear" with respect to the loading. © 2010 Taylor & Francis Group, London.