The Response Surface Method Based On Fem And Its Application To Reliability Analysis For Gravity Dams

The gravity dam plays an important role in hydraulic engineering. The problems of strength and stability of gravity dam for the sake of safety need be highly considered in duration of design, construction and work. The main task of structural reliability is to study the influence of uncertainties on structures. Reliability analysis of gravity dam is significant to its design, construction and management. Its entire study has important significance in economy of structural design, and structural safety. The reliability of gravity dam has been analysis by stochastic finite element method in this article, the main works of this thesis are as follows:1. It builds three-dimensional finite element model of gravity dam, and makes a analysis file which includs a complete cycle simulation analysis based on the parametric design language APDL of ANSYS in the article. The major work is: running analysis file that contains the order flow with software ANSYS, initializing the probability of design, and building date-base which for design probability of the finite element analysis.2. The reliability of intensity for the two-dimensional plane of concrete gravity dam issues is researched with the method of Monte Carlo according to the variability of load.3. Considering the material parameters and the load changeability, the reliability of intensity and stability for the three-dimensional finite element model of concrete gravity dam is researched with the response surface method. As the upstream water level, the condensational force against sliding, the friction coefficient correlation and the uplift pressure etc are random variables, the influence of its coefficient of variation to the reliability index is discussed.4. The correlation of the random input and output variables is researched.5. Taking the four-parameter model of the Concrete damage model into account, the reliability of intensity and stability for the concrete gravity dam is researched and the sensitivity of the random correlation were calculated.