OPTIMIZATION OF MAINTENANCE STRATEGY FOR CORRODED REINFORCED CONCRETE COLUMNS UPON GAMMA PROCESS

With the continuous degradation of in-service reinforced concrete (RC) structures, owners are urgently concerned about managing and maintaining a sea of RC members at the proper time with limited funds. Thusly, an optimized approach for the maintenance strategy of corrosion-damaged RC columns is presented upon the gamma process. By analyzing the performance deterioration of the corroded RC columns, proposed are the calculation models for estimating the residual bearing capacity under different damaged levels and various loading conditions. Meanwhile, the gamma process is adopted here to predict the failure probability of corroded columns by considering the uncertainty of structural deterioration. Moreover, the optimal maintenance time of the structure is determined by balancing the maintenance cost and the risk of structural failure. A numerical example is given to demonstrate the effectiveness of the models proposed. The results show that: the residual bearing capacity of RC columns can be significantly affected by the rebar corrosion level and load condition; when the allowable degradation limit of the corroded structure is smaller, the optimal maintenance time of the structure is advanced, and the corresponding expected relative cost increases.