Influence of test conditions on the shear modulus and damping ratio of K 0 consolidated Bohai marine clay

Soils surrounding offshore foundations experience complex stress paths under cyclic wave, wind, and earthquake loading, including triaxial compression, triaxial extension, and direct simple shear. Because clay dynamic properties depend strongly on stress path, data from a single stress condition may not represent in-situ behavior. This study examines dynamic shear modulus, damping ratio, and accumulated cyclic strain of K0-consolidated remolded saturated Bohai clay under these three stress states through cyclic triaxial compression, triaxial extension, and direct simple shear tests. At the same accumulated strain, dynamic and normalized shear moduli are highest in compression, followed by extension, and lowest in direct simple shear. Damping ratio shows less consistent variation among stress paths, further confirming its stress-path dependence. The findings support unified prediction models for clay dynamic properties across stress paths and improve assessment of offshore foundation response. The results highlight the need for representative multi-path testing in offshore foundation design and assessment.