Inclined Pullout Capacity of Suction Anchors in Clay over Silty Sand

Abstract

This study presents a range of numerical modeling to evaluate the pullout capability of suction anchors subjected to inclined mooring loading in a clay-over-silty-sand deposit. Comprehensive numerical models were generated, which were validated against existing centrifuge testing and numerical modeling results. A parametric study was then carried out to assess the effects of the anchor length, padeye location, mooring angle, and layered deposits on the pullout capacity of suction anchors. According to the numerical simulation results, the following key design factors were obtained: (1) the optimal padeye position, (2) the ultimate horizontal and vertical pullout abilities, and (3) the horizontal load distributions at different padeyes. A simple framework of calculating the combined VH surfaces of the anchors was developed for preliminary prediction of the pullout capacity of suction anchors in a clay-over-silty-sand deposit that provides the optimized location of padeyes and more accurate prediction for the holding capacity of anchor. The design method proposed by this study can contribute to optimize and improve the current design guideline for more accurately predicting the bearing capacity of anchors in clay-over-silty-sand soil deposits.