Research On Bearing Capacity Of Corroded Reinforcement Concrete Component

Reinforcement corrosion can directly affect structure’s applicability and safety,accidents caused by structure failure happen sometime. How to evaluate these corrodedstructures and predict their residual capacity is an urgent problem in current civilengineering. This article research on from three respects mainly: the mechanism ofreinforcement corrosion in concrete and the study of electrochemical acceleratedcorrosion experiment, non-rust finite element model validation and the corroded finiteelement simulation study.Firstly, the mechanism of reinforcement corrosion in concrete is analyzed deeply inthe paper. There are two steps to be corroded for reinforcement in concrete. At first,reinforcement surface passivated membrane is damaged by concrete neutralization andchloride penetration, then the reinforcement is activated renewedly without protection,at last the bar is corroded. Based on the mechanism of reinforcement corrosion inconcrete, the study of electrochemical accelerated corrosion experiment is done, thestudy of the correlation between all kinds of corrosion experiments and actual structureis also analyzed, which provides theoretical basis to design the electrochemicalaccelerated corrosion experiment.Secondly, the experiment research and the finite element model validation is done.Six reinforced concrete simply supported beams are made, the scantling is morepractical. A new tool of stirrup kinking is designed. A new insulation level modes isadopted at the contact position between the longitudinal reinforcement and the stirrup.Distributive girder, reaction beam and template are designed and built. By the loadingtest of simply supported beams, the following conclusions can be drawn: the non-rustfinite element model is reasonable, which prepares for the numerical simulation on loadcarrying capacity of corroded RC beam considering Bond-Slip.Finally, Based on the Bond-Slip between the steel bars and concrete, the finiteelement models of reinforcement concrete simply supported beam with differentcorrosion rates are built for analyzing the load carrying capacity of corrodedreinforcement concrete beam. In the model SOLID65, LINK8and Combine39are usedto simulate concrete, steel bar and bond-slip between bars and concrete in ANSYS. The effect of corrosion ratio on bonding force between bars and concrete are simulated byadjusting the parameter of combine39. Besides, the area reduction of bar’s section anddecrease of yielding stress are also considering for calculating the load carrying capacityof RC beam under different corrosion ratios. The results shows with the corrosion ratioincreasing the stiffness of beam should decrease, slip between bars and concrete shouldbe larger, the load carrying capacity should obviously decrease and ductile failureshould turn to brittle failure.