Study On Method Of Cause And Stabilization Of Cracks In Concrete Dams

Combining with prototype observation data of Chen Cun dam, the correlative methods of cause and stabilization of dam's cracks in running course are studied by using mathematical theories and mechanical methods. The main contents are as follows.(1) The cause of concrete dam's crack is analyzed, and the main cause mining system of crack is trussed based on B/S pattern. Combining rough set theory with neural network, the realized method of cause mining of crack is presented, and the main cause of crack was mined by living example.(2) The established method of gray prediction model, BPNN model and statistical prediction model are discussed. Aiming at nonlinear dynamic characteristic of crack, a nonlinear assembled prediction model is advanced based on wavelet neural network, and the relative program is developed, and the assembled prediction model is proved with measured data. The distinguished method of crack destabilization is researched, and two control guideline of dam's crack destabilization is discussed.(3) The simulation theory of temperature field and the calculative method of temperature field in Marc are analyzed, and the various finite element models of concrete dam's crack are contrasted. According to the above research, referenced to the engineering case, the temperature field is simulated, and the effect of load on the crack is discussed to estimate the rough position of crack.(4) The fractal character of crack is analyzed, and the crack is simulated to a fractal signal be constituted of different frequency. The DWT arithmetic of ameliorative FFT is applied to distill secular component of crack. Finally, the method could approximately be used to analyze stabilization of crack, and the effect of method is proved based on example.(5) The crack simulation theory using multiple-node element and contact model and the realized approach of the theory in Marc is discussed, and the relation between COT and load is studied by using simulation. According to the above analysis and control guideline, the diagnostic and prediction model of crack destabilization is discussed.