Static And Seismic Ressponse Analysis Of Yunfeng Concrete Gravity Dam

Concrete gravity dam, which has many advantages including security, simplicity of design and construction, better applicability to terrain and geology condition and can easily solve difficulties caused by construction diversion and permanent flood discharge, is a dam type predominantly used in practical engineering presently. However, the designing principles used to control construction quantity and reliability of the gravity dam was mainly based on experiences. Therefore, it appears especially importance to develop and apply analytical and numerical methods for such gravity dam. Finite element method, which was developed in 1950s, is an efficient tool for complex structural analysis and had got satisfactory effects in the dam analysis.Till now, Yunfeng concrete gravity dam has served for more than 30 years. According to some regulation, it is necessary to evaluate its security. Based on its service condition, geology situation and load property, it is essential to make further analysis, so that more practical results can be got. Therefore, except for the basis of observations, model experiments and field surveys, it is necessary to fulfill numerical simulation of the dam applying a modern structural analysis method-finite element method, thus reasonable appraisal can be achieved about the security of the dam. As a result, accident can be avoided.Dam 53 of Yunfeng Concrete Gravity Dam was computed using finite element method in this paper. Considering that the axial length of the dam, it was treated as plane strain problem. Firstly, fundamental formulations of finite element method about plane problem in elastic mechanics were deduced, some principles about concrete gravity dam were discussed, stress of concrete gravity dam under static load were solved. Secondly, to analyze seismic response of the concrete gravity dam, subspace iterative method was applied to compute free vibration period of the dam, time integration method was builtup for the seismic time history analysis and formulation of coupled vibration of reservoir water and dam were also deduced. Finally, results of Dam 53 of Yunfeng dam computed under various static and seismic conditions were analyzed respectively, then, relevant engineering measurements were proposed according to various condition.