Study on the creep behavior of Tianjin marine soft clays and its improved Mesri model

Abstract

Abstract Marine soft clays are widely distributed in coastal areas. Owing to their strong creep properties, soft clay foundations undergo significant post-construction settlement, thereby affecting the life cycle of buildings. In this study, the creep behavior of Tianjin marine soft clays was investigated by consolidated-undrained triaxial creep tests. Based on the creep test results and the Mesri creep model and by treating the final clay deformation under each increment of load as the initial strain, an improved Mesri creep model that describes both the stress-strain and strain-time relationships using hyperbolic functions was established. The creep curves under various levels of cell pressure and deviatoric stress showed notable decay and stable creep characteristics but contained no accelerated creep stage. The stress-strain isochronous curves exhibited notably nonlinear characteristics. Relative to the results calculated by the Singh-Mitchell and Mesri models, the results calculated by the improved Mesri model were in better agreement with the test results, which suggests that the established model is suitable for describing the creep behavior of Tianjin marine soft clays and can provide a reference for predicting the long-term settlement of foundations.