Research On Rapid Calculation Method For Nonlinear Numerical Analysis Of High CFRD

With the rapid development of water conservancy and hydropower construction in China, height of CFRD is constantly refreshed. Shuibuya dam has been built and it is the highest CFRD in the world. Moverover, the300m high CFRD is also under planning to research. The sites of already built and proposed dam are located in the place of complex topography and geology. With the gradual increase of the height and dam, problems of stress and deformation of dams are becoming more and more outstanding. Better analysis of stress and deformation of CFRD is very important to the design and construction of the dam.Numerical analysis of high CFRD is a very complicated nonlinear finite element problem. Using the finite element method, more number of grids should be adopted in order to get better numerical calculation due to high CFRD scale increases. If making encryption measures, the grid number is even large. These bring very great difficulty for calculation. Former general direct method in memory and computational efficiency can’t meet the needs of computing. In order to save memory and improve the computing speed and accuracy, we need to seek a new calculation method. It is not only of great theoretical significance to the numerical simulation of high CFRD, but also has profound significance to engineering practice. In order to solve this problem, this paper has carried out the following three researches:1. The paper studies the method for preprocessing the matrix, the SSOR-PCG method, the improved iterative format, and the general matrix storage technology. Combined with the need of static finite element calculation of earth-rockfill dam, we present the rapid method using row compression sparse format stores total matrix and making use of SSOR-PCG iterative format to solve large linear equations, and the method to realize a rapid programming. Then the Visual Fortran language is adopted to compile the three-dimensional finite element program for static calculation of earth and rockfill dams based on rapid calculation method.2. Select inerratic CFRD as an example, by adopting the method of different density, get two grid models with different density, and then rapid calculation method and direct method were used for finite element analysis of the inerratic CFRD. The correctness of rapid calculation method is verified by applying to the three-dimensional finite element programming. The efficiency of the two calculation methods are compared, and it verified the feasibility of rapid calculation method being applied to the large-scale finite element calculation. 3. Taking the Shuibuya concrete faced rockfill dam as engineering example, three dimensional finite element model is established. Stress and deformation of Shuibuya concrete faced rockfill dam under different working conditions are calculated by using the program. The result of the stress and deformation of the panel and dam body are analyzed.