Elastic and plastic wetting mechanical parameters of rockfill based on deformation law

Wetting deformation is part of the main post-completion deformation of earth-rock dams, which has important influences on the stress deformation behavior of dam body and the safety of dam body for the initial impoundment. Based on the previous research results of wetting deformation characteristics, the proposed wetting deformation model and further comprehensive analysis of a large number of wetting test results, the relationship between wetting strains and their variation rules are summarized and improved, and the elastic and plastic mechanical parameters representing this characteristic are deduced. Under the framework of the nonlinear elasticity theory, a new formula for calculating the Poisson's ratio of wetting is proposed, and the close relationship among the wetting Poisson's ratio, the average effective stress $p$ and the generalized shear stress $q$ is established. In the framework of the plasticity theory, an accurate wetting dilatancy equation is proposed. It is found that the correlation coefficient between the calculated results of the Poisson's ratio and the dilatancy ratio proposed in this study and the test data is above 0.95. Therefore, the proposed methods for the wetting Poisson's ratio and the wetting dilatancy ratio are generally applicable, accurate and reliable, and the research results can provide important reference and support for the study of the wetting deformation characteristics of rockfill and the elastic or plastic simulation of the wetting deformation of rockfill dams.