Abstract: Due to the soil inside the suction caisson, the suction caisson and other marine foundations demonstrate a significant difference in the uplift characteristics. For suction caissons subjected to primarily vertical tensile loads, there exist three different failure modes, “slide failure”, “bottom resistance failure” and “reversed bearing capacity failure”. Different drainage conditions at the bottom of the caisson control the applicable failure mode. In this paper, efforts are made to investigate the suction caissons as a type of foundation for the underwater structures. Numerical analyses are performed to simulate the working mechanism and evaluate the resistance of the reversed bearing capacity failure mode. The most appropriate design method was also proposed through experiments and theoretic analysis.

Key words: Suction Caisson, Uplift, Reversed Bearing Capacity Failure, Finite Element Analysis