Utilizing Crushed Limestone Fine Wastes in Algeria as Fillers in Cement Pastes

In Algeria, more than thousand of aggregate crushing station produces annually about 68 million tons of aggregates, essentially of calcareous nature. Unfortunately, more than 20% of manufactured sands are unsuitable to be used as construction sands because of their high fines content that largely exceed the current standard that limit the maximum value to 12%. Similarly, the limestone fillers, which also result from the limestone rocks crushing process, are regarded as inadequate residues and in consequence unexploited. To improve the situation, it is important to improve all the aggregates and sands with high filler content and more particularly sands and the limestone fillers itself. This has favourable effect not only on the economy of the country but also the environment. This paper shows the influence of the characteristics of Algerian limestone fine (proportioning, fineness) on the physical properties, the mechanical performance and durability of cements pastes made with various ratios of water to binder. Obtained results show that the replacement of part of cement by these limestone fillers can improve significantly the mechanical resistance, the workability. This study also shows that the limestone fillers not only have physical effect but also an improved chemical activity by producing new hydrated compounds such as the carboaluminates [2]

Keywords:

Limestone fillers , Cement paste , Mechanical resistance , Carboaluminate