Progress and research challenges in concrete durability: ionic transport, electrochemical rehabilitation and service life prediction

Concrete durability degradation problems have received considerable attention in both research field and concrete industry during recent decades. To better understand the underlying mechanisms, various numerical models have been put forward aiming at widely concerned scientific issues involved in the entire life cycle of concrete structures: ionic transport in porous medium, degradations induced by multiple factors, as well as the prediction and rehabilitation method to prolong the service life. This letter aims to summarise the major contributions to these interrelated scientific issues particularly from the modelling perspective. The digital characterization of concrete heterogeneity and its influence on ionic transport behaviour will be firstly reviewed. Subsequently, concrete deterioration mechanisms induced by various factors and their internal coupling relationships are discussed in details. Meanwhile, promising electrochemical repair techniques with multi-fold advantages including chloride removal, corrosion inhibition, ASR mitigation and crack repair are systematically summarized. Finally, existing research gaps and future opportunities in these areas have also been visited, which is hoped to break the ice in this challenging field and promote the sustainable development of the concrete industry.