Mechanical characterization of concrete produced with recycled lightweight expanded clay aggregate concrete

In this paper the main mechanical properties of concrete produced with recycled aggregates obtained from crushing both structural and non-structural lightweight concrete are characterized. Various concrete mixes with replacement ratios of 20%, 50% and 100% of two types of coarse lightweight aggregates (LWA) by recycled lightweight concrete aggregates (RLCA) were studied in terms of their compressive strength, tensile strength, modulus of elasticity and abrasion resistance. Generally the experimental results show that all the studied properties are improved with the introduction of RLCA. In particular, concrete with RLCA has higher structural efficiency than the reference concrete, with LWA alone. It is thus concluded that more cost-effective structural lightweight concrete (LWC) can be produced with the introduction of RLCA. Moreover, it is shown that the RLCA obtained from non-structural lightweight concrete can be used to produce structural LWC. There is a slight reduction of the concrete's mechanical properties when the stronger LWA is replaced with the more porous RLCA obtained from non-structural lightweight concrete.