Limestone powder

Abstract

Limestone has been successfully used as a constituent of cement and concrete for decades. Fine limestone is commonly included in Portland cement by intergrinding, resulting in an optimal particle size distribution of the modified cement. In other applications, limestone powder is added separately from cement, for producing more stable and robust mixes, especially self-compacting concrete. This chapter examines the performance of limestone modified Portland cement and concrete. The review comprises the effects on cement hydration in relation with the fineness of the limestone, on the fresh properties of mortar and concrete (including its role in self-compacting concrete), and on the strength development in the hardened state. Complementarily, comments regarding sulphate attack and environmental benefits of the use of limestone modified cement are included. Limestone is an effective constituent of cement and concrete, and comparative analyses should always be made to mixes produced to the same strength. In this way, it has to be regarded as a supplementary cementitious material when included by intergrinding with cement clinker, or as a filler when added separately to concrete.