Influence of both stirrup spacing and anchorage performance on residual strength of corroded RC beams

Abstract

In this study, the influences of both stirrup spacing and anchorage performance on the residual strength of corroded RC beams are investigated. With the increase of stirrup spacing, the applied load is easily transferred to the anchorage region, and with the increase of the corrosion ratio of rebar, the mechanism of corroded RC beams shifts from beam action to arch action. In the case of non-uniform corrosion of the main rebar, the maximum deviation ratio of the corrosion ratio of main rebars is over 0.9, and the beam suffers flexural failure due to the yielding of rebars in the extremely corroded region. In the case of uniform corrosion of the main rebars, the maximum deviation ratio of the corrosion ratio of main rebars is below 0.9, and there are two situations. If the bottom portions of the stirrups are sufficient, the applied load is restricted in the support span, and the corroded beam presents a flexural failure mode. On the other hand, if the bottom portions of the stirrups are insufficient, the applied load is transferred to the anchorage, and the corroded beam is inclined to suffer bond failure. Moreover, when the beam suffers bond failure, the residual strength depends on the anchorage performance. Copyright © 2011 Japan Concrete Institute.