MECHANICAL PROPERTIES AND DURABILITY OF CONCRETE MADE WITH PORTLAND LIMESTONE CEMENT

European countries have a great deal of experience in the use of Portland Limestone Cements (PLC). In Latin America, most of the cement plants use limestone as a raw material and an increase in cement production is expected in the next few years. The manufacture of this cement would represent a rapid increase of production without environmental consequences. This paper synthesizes data from a research program carried out over two years to determine the effects of limestone filler on concrete and mortar behavior. At early age, the influence of limestone filler on workability, bleeding, initial curing and mechanical behavior (modulus of elasticity, compressive and tensile strength) was studied. Sulfate resistance and chloride penetration, the most important durability problems related with PLC, were also studied. The addition of slag was also investigated to improve the long-term strength and the durability of PLC. Results show that cements containing around 10% of limestone filler provide similar or better mechanical behavior than portland cement concrete, without compromising their durability properties where low chloride diffusion and high sulfate resistance is required. In this case, the environmental impact of cement manufacture decreases because the energy consumption and the carbon dioxide emission are reduced per ton of cement and the combination with supplementary cementing materials (slag, fly ash or natural pozzolan) can improve these aspects.