Thermal effects on the dynamic properties of marine sediment under long-term low cyclic stress

Abstract

Thermal problems may be encountered in offshore engineering applications, such as pipeline engineering activities and submarine nuclear waste storage. However, few studies have focused on the behaviours of marine sediment involved temperatures, especially under long-term low cyclic loads. In this study, a series of undrained temperature-controlled triaxial tests were carried out to study the thermal effects on the dynamic properties of marine sediment from the South China Sea (SCS) under long-term low cyclic loading. The experimental tests were performed at different temperatures and cyclic stress ratios (CSRs). The dynamic deformation, pore pressure and degradation of the strength of the samples were measured and analyzed. Two modified models for predicting the pore pressure and degradation of marine sediment are presented based on the experimental data. The results indicate that the temperature-induced pore pressure increases with increasing temperature as a power function without draining and loading. The axial strain, loading-induced pore pressure and degradation index decrease with increasing temperature. The CSRs have a substantial influence on the axial strain and loading -induced pore pressure.