Abstract：According to the engineering and dynamic characteristics of certain clay，the relationship between dynamic and static elastic modulus of the clay with different water contents has been studied by standard compaction test，compression test，wave velocity measurement and analysis of dynamic and static elastic parameters of seven clay samples. The ratio of water content to density is used as a variable to study dynamic，static elastic parameters. The transformations of dynamic，static elastic modulus and dynamic，static Poisson¢s ratios have been constructed. The test results indicate that：(1) the relationship between dynamic or static elastic modulus and water content is a cubic curve，and so are the dynamic and static Poisson¢s ratios. The dynamic and static moduli decrease while static and dynamic Poisson¢s ratios firstly decease and then increase when water content increases；(2) the cubic curve is also suitable for the relationship between the ratio of dynamic to static elastic modulus and the ratio of water content to density. The ratio of dynamic to static elastic modulus increases while the ratio of the static to dynamic Poisson¢s ratio firstly deceases and then increases when the ratio of water content to density increases；(3) the dynamic elastic modulus is larger than the static one；but the dynamic Poisson¢s ratio is smaller than the static Poisson¢s ratio；(4) the ratio of water content to density as transformation variable between dynamic and static elastic parameters has high fitting accuracy；(5) the static and dynamic Poisson¢s ratios vary smaller than the elastic modulus when the water content changes and the similar results have been gotten when the ratio of the water content to density changes. This research presents the experimental basis for the application of dynamic and static elastic moduli of clay in engineering and also provides a new method to study the relationship between the dynamic and the static elastic modulus of clay.
