Numerical Simulation Study Of Concrete Gravity Dam Reinforced With FRP

In High-Intensity Earthquake Region, Seismic performance of concrete gravity is directly related to the safety of the vast region downstream industrial and agricultural production and people’s lives and property, which has a particular practical significance. Currently, the main anti-seismic measure of dam is reinforcement, so reinforcement material has become one of the main research topic. In recent years, Fiber Reinforced Polymer is widely used in civil engineering. In this paper, Koyna dam was taken as the research object, discussed improvement against static and dynamic loads after local enhancement measures with FRP through the numerical simulation. The research contents include:(1) The numerical model of concrete structure reinforced with FRP is established. Concrete is simulated by the MISO model, FRP is assumed as linear elastic, the interface is modeled using the simplified model by Lu. Through test results of beams in the literature to verify this model. The crack distribution and failure pattern of the beam with or without reinforcement, the stress distribution of FRP under loading of different levels, and the mechanism of the concrete/FRP interface are analyzed specifically. The numerical results are in well agreement with the experimental results obtained lately, demonstrating the effectiveness of the model. It provides theory basis for gravity dam reinforced with FRP.(2) Study on the concrete gravity dam reinforced with FRP sheet. Take the case of Koyna, the effects and mechanism of FRP sheet reinforced on the dam heel and near the jetty head slope were studied. First through the destruction analysis of dam under the action of water head overload, studied the static strengthening effect of FRP materials; And then through the concrete gravity dam nonlinear dynamic time history analysis under earthquake excitation, studied the seismic strengthening effect of FRP materials. By comparing the crack distribution pattern, crack extension process, displacement and displacement acceleration of dam crest, principal stress distribution and so on with and without FRP sheet under the static and dynamic load, to reveal the reinforcement effect and mechanism of FRP sheet. The study shows that the crack development can be effectively alleviated if the weak parts of concrete gravity dam is surface-strengthened by FRP sheet, and this measure also plays a certain role in distributing cracking of concrete.(3) Study on the concrete gravity dam reinforced with FRP rebars. Two kinds of reinforcement methods with prestressed FRP rebars were used and the two ends of the FRP rebars are respectively inserted into the dam and the bedrock, studying the reinforcement effects through numerical simulation. The study shows that this measure can reduce crack extension speed, which can improve the ability of the dam against static and dynamic load.