Experimental Study on the Use of Natural zeolites as Partial Replacement for Cement in Concrete

Study on the use of natural zeolite as partial replacement for cement in concrete has been carried out in China and in other countries since early 1980. However, very few information has been reported in Indonesia on this subject, although the availability of the natural zeolite in the country is abundant. So far, natural zeolite is only utilized in the agricultural sector. In this research, natural zeolite has been used to partially substitute the ordinary Portland cement (OPC) in concrete. The presence of silicon dioxide in natural zeolite was expected to increase the concrete strength through reaction with the calcium hydroxide from the hydration of OPC. However, results from the investigation revealed that the compressive strength, the tensile splitting strength and the modulus of elasticity of concrete containing natural zeolite decreased with the increase of natural zeolites content