Impact resistance of RC beams with reinforcement corrosion: Experimental observations. (10th December 2020) - Tamai, Hiroki
Highlights: Static and impact resistance of corroded RC beams were studied by experimentally. It is the first experiment study on repetitive impact resistance of corroded beams. The effect of loading conditions on the fracture of corroded beams was investigated. The effect of corrosion was heightened in cases of high-rate dynamic loading. Fracture process of corroded beams under repetitive impact were investigated. Abstract: Reinforcing steel corrosion is a serious problem that may negatively impact the safety and serviceability of reinforced concrete (RC) structures. To properly maintain and manage RC structures with corroded reinforcement, it is necessary to clarify the relationship between the degree of deterioration and the remaining load capacity. Most previous studies have focused on evaluating the load-bearing capacity of RC beams with corroded reinforcement subjected to quasi-static loads. In contrast, there are relatively few studies on the behavior of corroded RC beams subjected to impact loads, as might occur during natural disasters. In this study, RC beam specimens with varying degrees of reinforcement corrosion are subjected to quasi-static and falling-weight impact load tests. Electrolytical means are employed to induce corrosion. The test results are used to evaluate: 1) the impact resistance of RC beams deteriorated by reinforcement corrosion, including the effects of repetitive impact; and 2) the differing effects of corrosion on static load-carrying performance and impact resistance. The results indicate that, for corrosion degrees higher than 10%, the impact resistance is significantly reduced and the failure mode becomes more brittle. The brittleness can be attributed to, at least in part, interactions between flexural cracking caused by the loading and preexisting damage associated with the corrosion process. Furthermore, the results reveal that reinforcement corrosion has a greater influence on impact resistance than on quasi-static load capacity.