Service life prediction model for chloride-induced corrosion of concrete-steel tubular columns

Abstract

<p>Service life prediction of concrete-steel tubular columns in the marine environment is one of the most important criteria. Generally, the chloride-induced corrosion initiation time is considered the end of the service life. Even though cover cracking and crack propagation time contribute significantly to the estimation of service life, especially for fiber-reinforced concrete. In this study, we proposed a service life prediction model for concrete-steel tubular columns considering cover cracking and crack propagation time and validated it from the experimental results. The effect of the mechanical properties of the rust layer and infiltration of rust into open cracks were considered for cover cracking time. Experimental findings were compared to predictions made by the proposed model, indicating that the suggested model can predict cover cracking time for accelerated conditions with some discrepancies. A rate of loading correction was applied to correlate the accelerated corrosion time to real corrosion time. An empirical crack propagation model was developed based on experimental data, and the time until the limited crack width of 1.0 mm was calculated. This model showed that considering cover cracking and crack propagation can extend the service life by up to 20%. Furthermore, a practical model for predicting residual mechanical performance was developed based on experimental data.</p>