Transport and Durability Properties of Self-Consolidating Concrete Using Three Types of Lightweight Aggregates

This paper presents the mass transport properties and some durability aspects of lightweight self-consolidating concrete (LWSCC) using three types of lightweight aggregates having different densities-namely furnace slag (FS), expanded clay (EC), and expanded shale (ESH). The properties of developed LWSCC mixtures were evaluated through comprehensive investigations on porosity and water absorption, sorptivity, rapid chloride permeability (RCP), corrosion resistance (in terms of loss of bond strength and reinforcing bar mass), and drying shrinkage. EC-LWSCC mixtures showed highest water absorption, sorptivity, and porosity when compared with FS/ESH-LWSCCs, where a reduction in sorptivity was observed with age. Consequently, EC-LWSCC mixtures experienced highest relative RCP values; however, all mixtures exhibited improved performance with age to satisfy the low permeability criterion by 91 days. Corrosion resistance of LWSCC mixtures was found to be primarily determined by the type, quality, and properties of aggregates. LWSCC made with EC aggregates showed the highest bond strength loss due to reinforcing bar corrosion. All LWSCC mixtures exhibited drying shrinkage of >= 600 microstrain at 112 days; a substantial increase of the drying shrinkage values were reported for mixtures made of aggregates with higher absorption capacity (such as ESH) and lower coarse-to-fine aggregate ratio.