Triaxial tests on creep characteristics of coastal soft soils

To explore the creep properties of typical structural soft clay in the coastal area of Tianjin, a series of triaxial creep tests are carried out considering the factors such as confining pressure, loading ratio, frequency and so on. The stress-strain-time curves of coastal soft clay under different conditions are obtained. According to the comparison of indoor tests between the original soils and the soils under different experimental conditions, the accelerated creep properties are found. The results show that the coastal silt clay in Tianjin exhibits nonlinear rheological properties of stress-strain, and its creep curves are attenuated. The creep deformation mostly occurs in its early stage, and the deformation tends to be a constant value with the passage of time. Under static loads, the greater the confining pressure, the greater the initial creep rate. Under the same initial loading pressure, the failure stress decreases with the increase of the loading ratio. Under cyclic loads and the same experimental conditions, there exist a structural yield stress and a critical frequency. Once exceeding the two critical value, the phenomenon of creep failure will occur.