Experimental Study On The Bonding Behavior Of Reinforced And Carbonized Concrete In Cyclic Loading

The carbonation is one of the main factors which have caused the durabilitydamage to the concrete structure, and which could have a great impact on mechanicalproperties of concrete. The carbonation of concrete has changed the performance ofconcrete itself which lead to the decline in bond performance of reinforced concretestructures.However, in view of the theory of steel reinforcement and the carbonationconcrete bonding performance is still lack of the data and the test research.Thecarbonation reduces the alkalinity of concrete which could make the concrete lose theprotection from the rebar, and also change the bonding behavior of concrete and rebar.However, for now, the study on the bond property of carbonated reinforced concrete isnot mature enough. Thus, this thesis, which is aiming at experimental study on thebonding behavior of carbonated reinforced concrete in cyclic load, is not only theimprovement for the existing anti-seismic property appraisal theory of reinforcedconcrete structures, but also has great theoretical significance and engineering value tothe disaster prevention and reduction of concrete structure.First of all, this thesis attempt to do a complete carbonation experiment on theC20、C30and C40three batches of reinforced concrete samples,and use the standardcube specimens to deteimin the normal and completely carbonation concrete’s tensilestrength.Then through repeated loading test,each sample should be cyclic loaded till thebond-slip curves of those were gained. Besides, the non-carbonation samples in thesame batch should be done in the same way till their bond-slip curves were obtained aswell.Secondly, this thesis analyzes the affection of carbonation to the bond performance of reinforced concrete structure by comparing those bond-slip curves we got. With theintroduction of bond stress degradation rate, the thesis has illustrated the impact ofrepeated loading cycles on the bonding properties of reinforced concrete, and alsocomprehensively analyzed the different bonding performance between the non-carb-onated and fully carbonated reinforced concrete specimens.At last, based on the experiments, this thesis has comprehensively analyzed thebonding performance of carbonated reinforced concrete, especially how that wasaffected by concrete carbonating. Moreover, the constitutive relation is built, which laidthe foundation to further study the bonding behavior of carbonated reinforced concreteunder cyclic loading.The research result of this thesis could promote the development of the bondtheory;furthermore, it will provide the theoretical basis for instructions and engineeringpractice about bond performance of the carbonated reinforced concrete under the cyclicloading.