Triaxial creep characteristics and empirical model for saturated coral sand

The riaxial drainage creep tests are performed on saturated coral sand under different cell pressures and deviator stress levels. The results show that the cell pressure and deviator stress have significant effects on creep deformation. The specific performance is that when the deviator stress is large or the cell pressure is small, the creep deformation is large, and the creep phenomenon is obvious. The traditional Singh-Mitchell and Mesri creep models are used to describe the creep characteristics of coral sand. It is found that the calculated results of the two models are quite different from the test results under high deviator stress conditions, which cannot accurately describe the creep behavior of the coral sand. By analyzing the reasons for the large error between the model and the test results, the stress-strain and strain-time relationships are expressed by hyperbolic functions, and a new creep model is established. The predicted results of the new model are in good agreement with the test results.