LAUSR

ABSTRACT Skirted semi-deep foundation becomes an increasingly prevalent option for offshore and onshore structures. Behavior of these foundations on clay with constant and variable undrained shear strength is required to be investigated. In this study, finite element analyses are conducted to evaluate vertical bearing capacity. The effect of different factors, including embedment depth ratio, soil-skirt interface property, and shear strength profile have been studied and outcomes compared to previous researches. The results showed that load carrying behavior enhances with increasing the skirt depth and roughness and decreasing the degree of soil heterogeneity. Foundation capacity for typical skirt roughness condition in practical design can be calculated assuming rough soil-skirt interface due to the negligible disparity of bearing capacity factors for skirt friction coefficients of 0.5 to 1. Furthermore, a new solution based on vertical bearing capacity ratio of semi-deep to surface foundation (VBCR) is proposed which indicates the efficiency of utilizing skirt.