Study on the anisotropic small strain stiffness of marine clay in China using bender elements

Abstract

Small strain stiffness anisotropy of marine soils plays an important role in determining the natural frequency of offshore wind turbine structures. The small strain stiffness anisotropy is contingent on stress anisotropy and fabric anisotropy, with the latter being assessable via stiffness anisotropy under isotropic stress conditions. In this study, the small strain stiffness of marine clay obtained from the site of an offshore wind farm on the southeast coast of China was measured using a bender element. The effects of void ratio, effective mean pressure, and overconsolidation ratio on small strain stiffness were investigated and the related empirical equations were proposed for predicting the small strain stiffness of the marine clay. Furthermore, the small strain stiffness anisotropy of the marine clay under isotropic consolidation was also investigated. The findings revealed remarkable anisotropy in the small strain stiffness of the tested marine clay.