A review and comparative analysis of corrosion-induced time to first crack models

Generally, the time to repair/replacement of reinforced concrete structures due to chloride-induced corrosion is determined by cracking of the concrete cover. Hence, many researchers have focused on the development of calculation methods for this time-to-first-crack. This paper stemmed from the authors’ search to find a reliable, consistent model for predicting future condition state in a cracking limit state, service life structural model, and the confusion which arose from a multitude of different models postulating to give the most accurate results. Three well known mathematical models are examined and compared. The problems with them are illustrated and a modification, arising from an earlier trigonometrical derivation error, is also presented and directly paralleled with the original versions. This results in compliance with previous experimental results and so is ultimately proposed as a means of predicting time to crack initiation when the use of more advanced, computationally intensive FE models is inappropriate.

► This paper examines three well-known models for time-to-first-crack of concrete.
► The problems with them are described and illustrated.
► A modification to these models is presented.
► A model is proposed ultimately as being appropriate for network-level modeling.