| A continuous rise of crude-oil prices in the world. As renewable resource hydroelectric power plays more and more important role in energy supply, relaxing the bottleneck of resources that China encounters in the process of development in the 21st century. With implementing of the West Grand Development Strategy and"the project for delivering electriciy from the west to the east", one batch of high concrete dam is building or will be constructed in southwest in China. The reservoir capacities of these projects reach several billion cubic meters; and most of these projects build in strong earthquake region. Once the dams are failure, society and people will suffer from the disaster to economy development, people's life and,property. So seismic safety is a key problem in the design of dams. Effective structural measures are very useful in improving the safety of dam and intensifying the resistance of load.In this paper, based on the National Natural Science Foundation-funded projects"Deep high-pressure saturated unified multi-scale constitutive relation of concrete and static and dynamic model tests(50679006)". With the advancement of Ahai hydraulic engineering, this paper carries on physical and mechanical properties of emulation materials, dynamic model test study and finite element analysis on steel fiber reinforced concrete (SFRC) strengthened seismic mitigation measures for the dam. The main contents are organized as followed.(1) In large scale model shaking table test of concrete gravity dam, How to develop a type of similar model material to meet the similar requirements have been a noticeable focus. In order to obtain a ideal material for large scale. model test, this dissertation investigated the features of low strengthen-emulation concrete materials including their uniaxial proportions in tensile and compressive loadings, dynamic natures. The deformation and relationship of concrete under tensive and compressive loading were researched referring to mechanical properties of common concrete.(2) The characrisitics and component of the material were given. The design and analysis of the model material experiment were also described. The simulation theory and deign of the model dam sections were inroduced. Main influence factors in the model test were analyzed, such as damping, Poisson ratio, high-frequency modes, size of boundary,constraint conditions etc. Based on numerical analysis, several correction coefficients wereused to correcting the conversion of test results and response of crude model in the paper.(3)Experimental study were made to study the characteristics of RC so as to find the method to simulate the RC in the model test.In this papar embedded metal fiber four-point bending of beam reinforced concrete(RC). Based on an overall consideration of various factors,the method can improve ductility and wholeness of emulation concrete. Full range elastic-plastic program of RC and former are identified according to load-deflection curve.The method can be used to do dams strengthened with RC experiment.(4)Sectional experiments of the dynamic model were made to Ahai RCC dam and the results of the experiments were analyzed and compared. Four typical sections, such as water retaining dam section, overflow dam section, factory dam section and scouring dam section were included in the model test. Non-seismic measure and steelbar-strengthening measure of each monolith were considered respectively. The effect of the reinforcement bars on starting crack state and the entire safety of the dam was studied.(5)Based on ANASYS10.0 software, the nonlinear finite element analysis on reinforcement strengthend seismic mitigation measures of Jin'anqiao RCC dam is carried out in the paper. The effect of the allocated positions, numbers and forms of the reinforcement bars on starting crack state, crack propagation, crack penetration and the entire safety of the water-retaining monolith is numerically simulated by the concrete model based on nonlinear theory and fracture mechanics.(6) By multifactorial analysising the model test results and numerical conclusion, the paper shows that it is effective to appropriately adopt the reinforcement measures for seismic resistance of dams.
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