Chloride ingress into structural lightweight aggregate concrete in real marine environment

This study aims to characterize the chloride ingress into structural lightweight aggregate concrete (SLWAC) in real marine environment. For this, common normal weight concrete (NWC) and SLWAC produced with different water/binder ratios, types of aggregate and types and contents of binder were exposed to submerged, tidal and atmospheric conditions. Chloride profiles were obtained at 1 and 3 years of exposure and their chloride diffusion coefficients, Dcl, and surface chloride contents, Cs, were analysed. At least for water/cement ratios up to 0.55, Dcl was little affected by the type of aggregate, regardless of the exposure conditions. However, Cs and hence the chloride penetration at a given depth were higher in SLWAC with lightweight aggregates (LWA) of higher porosity or without a protective denser outer shell. SLWAC with dense LWA were able to achieve equivalent chloride penetration resistance to NWC with the same composition.