A SOLUTION FOR QUARRY LIMESTONE DUST RECYCLING

Quarry dust is a product of the extracting process. In quarrying activities, the rock is extracted and transformed into various sizes: as a waste, a fine aggregate generally useless to be disposed of and able to produce environmental pollution is produced. The disposal of this type of waste is a further cost of the extracting process, further it is a risk especially for subsoil reserves of wa-ter that can be easily reached during rainfalls and for the sea when quarries are close to the coast. The productive use of quarry dust with the double aim of disposal and protection of the environment seems a right strategy. The Italian-Maltese extracting industry covers a great segment in the world with a great produc-tion of fine waste that has become a problem to be solved rapidly. In some cases quarries are lo-cated close to protected areas and to the sea with higher risk for the environment (an example is the limestone extracting industry of Trapani). In this context, the paper reviews the strategies proposed in the use of limestone fine waste, especially for concrete, and discusses an experi-mental program aimed to observe the modification of the mechanical properties of concrete made by substituting partially the fine aggregate (sand) with the fine limestone waste produced in the area of Trapani.