Nonlinear Seismic Response Of Concrete Face Rockfill Dam Numerical Methods And Three-dimensional Effect

A number of high concrete-faced rockfill dams (CFRDs) with the height of more than 200m are being under construction or to be built in the southwest area of China with potentially heavy seismic activity, and these CFRDS are often located in complicated canyon of the river. Therefore, the safety of these high CFRDS subjected to strong earthquake shaking in addition to reservoiring becomes a crucial issue in governing their whole performance. In this thesis, nonlinear dynamic seismic response and three-dimensional effects of high concrete-faced rockfill dams are studied based on numerical finite element analyses.In order to incorporate the nonlinear characteristics of rockfill materials, the equivalent linearization procedure is implemented in three-dimensional finite element analyses. Modified versions of the computer codes THREES are updated in order to effectively capture the structural or geometrical characteristics of concrete-faced rockfill dams. The Hongjiadu concrete-faced rockfill dam is taken as an example. The three-dimensional effect on the dam dynamic response is studied by varying abutment slope, width of canyon and whole scale of CFRDS. Numerical results of dynamic analyses are presented and relevant conclusions are given which are instructive to the evaluation of earthquake-resistant, choosing dam site and design.Moreover, the step-by-step incremental-iterative numerical procedure with computer program CFRDSDB3 based on hypoplasticity bounding-surface constitutive model is developed and it is employed to perform nonlinear dynamic analyses of the Hongjiadu concrete-faced rockfill dam to earthquake shakening. Meaningful conclusions are given, and they will be valuable to the rational earthquake-resistant design of CFRDS.