Stochastic modeling for bond deterioration between rebar and concrete due to reinforcement corrosion

Abstract

Reinforcement corrosion has a significant impact on the bond behavior between rebars and concrete. Accelerated corrosion tests and pullout tests were conducted on 24 concrete cube specimens with embedded rebars to investigate the non-uniformity of corrosion and establish a deterministic model for the bond strength-slip relationship. Then, the probability distribution of the ultimate bond strength for 132 specimens, the peak slip for 79 specimens, and the stochastic process of the ultimate bond strength changing with the corrosion level for 204 specimens from previously published studies were analyzed. By introducing the probability distribution and stochastic process into this deterministic model, a stochastic model is suggested to evaluate the bond deterioration between the rebar and the concrete owing to the reinforcement corrosion. The results showed that: The non-uniformity of reinforcement corrosion was verified since the remaining diameters obeyed an extreme value I distribution. The ultimate bond strength and peak slip obeyed normal distributions and how the ultimate bond strength changed with the corrosion level was a normal stochastic process. The error percentage between the stochastic model and the test results was less than 5 %, indicating that the bond strength can be well predicted when giving a corrosion level.