Experimental Study On Flexural RC Members Strengthened With Prestressed Carbon Fiber Reinforced Polymer Plates

Along with the rapid development of national economy and the gradual improvement of people's living standards, people raise even higher claim to the quality of buildings and habited environment. Some old buildings need more factions, which makes those need to be strengthened. In addition a large number of buildings from 1950s to 1960s which have reached the whole life, need reinforcement too. Furthermore some existing new buildings have some problems because of design, construction and management and so on. The bridge structures have the same problems too. So that, the repair and strengthening of buildings become the hotspot besides the improvement of building quality.Strengthening with prestressed CFRP is a new strengthening technique which has been developed in the last decade. The strengthening method with prestressed CFRP improves the mechanic behavior of components by adhering the prestressed CFRP to components with special binding agent.According to the research project of traffic office of Hunan province, the experimental and theoretical study on flexural RC members strengthened with prestressed CFRP were carried out. The contents are as follows.1. Practical tensioners and a series of tensioning system of CFRP plate were invented to make the industrialization development of the strengthening method with prestressed CFRP.2. In the static test of small-size flexural members(2.2m~3.2m)with prestressed CFRP plates, there have been studied that the carrying capacity, flexural rigidity and crack resistance of the strengthened members. the gap of antistripping performance of prestressed and nonprestressed CFRP plate, the influence of different initial stress levels on strengthening effect.3. The strengthening engineering of the Jingang Bridge in Liuyang city with prestressed CFRP plates and the load test of the bridge was completed and the strengthening effect was evaluated. Some optical grating measuring points were settled on the CFRP plates to monitoring the influence of surrounding temperature, humidity, ultraviolet radiation, creep of concrete, vibration of vehicles and other factors to the prestressed CFRP plates and evaluate the long-term serviceability of the prestressing strengthening system.