Probabilistic Life Prediction for Reinforced Concrete Structures Subjected to Seasonal Corrosion-Fatigue Damage

Abstract

The coupled effect of corrosion and fatigue deteriorates the performance of reinforced concrete (RC) structures. This paper proposes a novel framework for the probabilistic life prediction of aging RC structures under seasonal corrosion-fatigue damage based on the fracture mechanics and equivalent initial flaw size concept. A series of fatigue crack growth tests of steel bars in air and solution environments are conducted to simulate the fatigue crack growth behavior of rebar in different seasons. The framework includes three critical deterioration stages: corrosion initiation–pure fatigue crack growth, competition between corrosion pit growth and fatigue crack propagation, and structural failure. The chloride ingress, cyclic load, corrosion pit growth, concrete cracking, seasonal environmental variation, and corrosion pit-induced stress concentration are considered. Following that, an uncertainty model is established to incorporate various uncertainties associated with the load and environment. The characteristics of different stages are discussed. A parametric analysis is also performed to illustrate the influence of stress concentration, concrete severe cracking, and seasonal environmental variation on the life prediction results. Several conclusions are drawn and future work is discussed based on the proposed study.