PROBABILISTIC RESISTANCE MODEL AND EXPERIMENTAL INVESTIGATION FOR CORRODED RC BRIDGES

It is known that it is very important to build a time-variant probabilistic resistance model for assessing a time-dependent performance, predicting remaining life and optimizing repair strategy for deteriorated RC bridges. Corrosion of steel rebar results in reducing its yield strength, changing the mechanical behavior of corroded reinforcing bars and affecting the bond behavior between concrete and reinforcing bars. The amount of corrosion loss of corroded reinforcing bars affects the failure mode of corroded steel bars. That is to say, the failure mode varies from ductile to fracture. This paper develops a probabilistic resistance model that quantitatively considers the influences of corrosion on the mechanical behavior, collapse mechanism and bond behavior of corroded reinforcing bars. The developed resistance model can capture the random and variability of deterioration mechanism, pitting corrosion distribution, geometrical sizes, corrosion propagation, failure modes and the calculation model of deteriorated RC structures. The accelerated corrosion test of RC structures and destructive testing of existing RC bridges demonstrated the correctness and reliability of the developed model.