Uplift Performance of Suction Foundations in Sandy Soils for Offshore Platforms

Suction foundations are widely used in the construction of offshore platforms. Their uplift resistance in sandy soil strata is crucial for evaluating the stability of offshore platforms. A scaled-down experimental device was developed to investigate the pull-out performance of suction-type foundations in sandy soil. The relationship between the pull-out performance of suction-type foundations under the influence of different factors (e.g. different uplift directions) and the uplift speed was discussed. The ABAQUS finite element explicit dynamic analysis method was used to study the influence of different drainage conditions, loading speeds, loading angles, and loading methods on the stress change, deformation, and bearing performance of the surrounding soil during the design stage of the suction foundation. The comprehensive testing and numerical analysis results revealed the pull-out performance of suction foundations in sandy soils. The results showed that the uplift performance of the suction foundation is affected by the uplift angle and speed. At low uplift angles, increasing the uplift speed can improve the ultimate bearing capacity of the suction foundation, while at high uplift angles, a lower uplift speed can help improve its uplift resistance. At the same time, the ultimate bearing capacity of the complete drainage simulation is generally higher, which can provide a more conservative safety estimate for engineering design.