Study On Engineering Characteristics Of Rockfill Materials And Stress-Strain In Concrete Face Rockfill Dam

In this paper the engineering characteristics of rockfill materials are systematically discussed and analyzed. Wetting experiments as well as rheological experiments of rockfill materials are carried out, aimed at their deformation behavior especially rheological characteristics and their effect on the deformation of dam body of Concrete Face Rockfill Dam (CFRD).The main contribution includes:(1) The development of CFRD and its study actuality are reviewed. The existing problems in the theoretical research of CFRD are then brought out.(2) The constitutive models of the rockfill materials are compared and some problems and factors that should be taken into account are put forward. The choice of interface elements is discussed.(3) The principle and the creep model of the rockfill materials are discussed, furthermore, an improved creep model considered confining pressure and axial loading is proposed.(4) The study actuality of engineering characteristics of rockfill materials and their trends are summarized. Their deformation and strength characteristics are also discussed. The wetting deformation experiments as well as their numerical analyses are carried out.(5) Creep tests of rockfill materials of a specified CFRD are firstly carried out to obtain the creep parameters that can be used to better understand the rheological characteristics of the materials. A large-scale triaxial apparatus is adopted for the tests .The tests are performed under three different confining pressures for each rockfill material, and three different kinds of axial loading is applied under each confining pressures. The rheology of the rockfill materials are presented and analyzed based on the test results, and the creep parameters are obtained.(6) Based on the parameters achieved in the rockfill creep experiments, the deformation characteristics of dam body of Gongboxia CFRD are studied through a contrast between considering rockfill creep deformation factors and not considering them. The rationality of the present creep model and the reliability of its creep parameters are verified. And an important reference to the design and construction of new building CFRD is offered.