The Influence Of Geologic Defects On The Evolution And Variation Of Concrete Dams

Owing to the significant influence of geological defects on evolution and variation of concrete dams, many models and methods pertinent to the problem are presented in this work. And how geological defects influence on evolution and variation of concrete dams are studied by applying the models and methods presented. At the same time, some methods are presented to diagnose the behavior variations of the dams. The main contents are as follows.(1) The engineering characters of geological defects detrimental to dam safety are investigated. Based on the investigation, the systematic geology-engineering-mechanics models are built up to evaluate the geological defects' influence on the evolution and variation of the gravity dam and arch dam. Then by use of monitoring data and Elman recurrent neural networks, the method to build up time series evolution model of geological defects is presented. And the application indicates that the method is effective.(2) Nonlinear rheological models of thick and zero-thickness structural planes are presented. And incremental expressions of finite element for simulating creep of the structural planes are derived.(3) Damage-reheological characters of rock structural planes are discussed, and the damage-reheological model for them is presented. Coupled creep and seepage equations for structural planes and equivalent continuum medium are derived. Creep and seepage coupled model for hybrid medium is presented, and FEM program for the coupled model is developed.(4) Deformation and stress evolution mechanism of gravity arch dams under the influence of geological defects is drawn out by the above numerical methods. And the rules how the strength, creep and seepage of geological defects influence on deformation and cracks evolution of the dams are derived.(5) Based on fractal theory, partial least squares, genetic simulated annealing algorithm and data fusion methods, three methods are presented to diagnose dam variation. And the methods are proved to be effective by the applications.