Carbonation-induced early corrosion propagation based service life assessment model (CECP-SAM)

Department of Civil Engineering, University of Hong Kong, Hong Kong, China

Abstract

Supplementary cementitious materials (SCMs) are widely used for sustainable concrete. However, this is challenged due to the deteriorated resistance towards carbonation-induced corrosion. This paper introduces the establishment of a novel carbonation-induced early corrosion propagation based service life assessment model (CECP-SAM). Except for concrete carbonation, this model is characterized by considering the early corrosion propagation (incipient cracking) and the use of supplementary cementitious materials. Based on experimental and numerical methods, the effects of binders, water/binder (W/B) ratio, cover thickness, rebar diameter, semi-carbonation zone, cathode-anode ratio on service life are investigated by CECP-SAM. The model is justified by using the results from a field investigation in Hong Kong. Performance-based service life equations and prescriptive design criterions are also given based on CECP- SAM.