Concrete made with zeolite and metakaolin: A comparison on the strength and durability properties

An experimental investigation was carried out to evaluate the mechanical and durability properties of concrete mixtures containing natural zeolite (NZ) and metakaolin (MK) in binary blended system up to 20% replacements. Concrete mixtures were evaluated for compressive strength, penetration of water under pressure and water absorption in 30 minutes and 24 hours at various ages up to 90 days. Water to binder ratio and total cementitious materials content were kept constant for all mixtures as 0.4 and 400 kg/m3 respectively. The results showed that despite the observed decrease of compressive strength of proposed composites, they gained enough strength at the later ages similar to that of normal concrete. Moreover, the results confirmed the beneficial effects of zeolite and metakaolin on the durability indexes of concrete which lead a green and environment-friendly concrete.