EXPERIMENTAL STUDY ON CREEP CHARACTERISTICS OF SATURATED SAND AND ITS INFLUENCING FACTORS

This paper studies the creep characteristics of saturated sand and its influencing factors. It carries out the high pressure unidirectional compression tests of different density,different grading methods and different loading methods. The test results show that the creep of sand mainly undergoes three stages:instantaneous deformation,rapid deformation and steady-state creep deformation; the compressive modulus increases with the increase of density. The weighted average particle size of samples prepared by similar grading method is 42.4%smaller than that by equivalent substitution method,and the compression modulus is 8%~18% higher. Different loading methods have a certain influence on the final deformation of the sample. After cyclic loading,the compression modulus of samples decreased by 4.3%~10.1%,and the final strain variable increased by 4.6%~6.0%. The statistical analysis of the test data shows that the power function can well fit the stress,deformation and time relationship of saturated sand soil,and finally the creep model is suitable for this sand soil. The research results can be applied to the design and evaluation of sand foundation.