Research On The Application Of FEM To The Mass Concrete Structure

In civil engineering, there are some typical problems such as temperature and creep of the mass concrete structure to be studied. Because of their explexity, only a few problems can get accute solutions.With the development of computer technology and numerical modeling techniques, many numerical methods have been established and applied to this field. Finite element method (FEM) is one of the most effective. The application of FEM to the temperature and creep of the mass concrete structure is studied in this thesis. The main works are listed as follows:(1) Some widely used numerical methods are summarized. The priciple of FEM and the application to temperature field and stress field are dissertated in detail.(2) Some typical concrete creep models are introduced. The advantages and disadvantages of these models and their applicable conditions are described generally. Especially, "Nortan creep law" and "Zhu bofang-H.X.Apytkohrh creep model" are expatitated thoroughly. The nonlinear analysis of mass concrete stucture is introduced.(3) On the base of "mixed-layer method", a method using different gridding indifferent regions is proposed. Then the application rules and applicable condition are introduced in detail.(4) The thermal parameters of concrete are studied in the thesis. And the thermal parameters fuction method is proposed.Compared with the traditional methods,a better precision can be obtained.(5) According to the theories and methods mentioned above,the program TEPSAC is developed. The baic structure and the main fuction of this program are introduced briefly. Some key techniques in programming are also presented. The program has been verified by some examples.(6) Simulation of the construction of RCC cofferdam in Three Gorges Project is taken as the example by this program, The result are quite good and can be used in the design and the construction of mass concrete structure.