Alkali-activated mortars from rock muds. Experimental mix-design and tests for the prototyping of sustainable building products

Several experiments on alkali-activated materials are focused on reducing raw materials and the reusing of scrabs of different supply chains in construction field. With the aim to increase the development of applied research in this sector, with direct repercussions and advantages for the environment footprint, at Politecnico di Torino are under development many tests concerning the mix-design of mortars and concretes with the use of waste and SRM from ornamental rocks quarries. In particular, the use of rock muds from the sawing process is an interesting application of SRM that, currently, are landfilled with relevant costs; in 2010, only for the Valle Ossola quarries district, the amount of the waste burial of these materials was 70.000,00 tons/year (source: Assograniti). After the recent economic crisis this amount was halved, more or less, but it’s still a relevant problem for the local activities, like as for the analogous ones of the other district of Luserna area in Piedmont. In addition, it must also be considered that the construction sector is also among the most impactful in terms of environmental footprint. In Europe, this field as a whole consumes 50% of extracted materials, emits 35% of greenhouse gases and produces 30% of waste (source: ARCADIA Project, Italian LCA Database, 2021). For these reasons, looking for new ways of reusing waste or by-products can meet several needs at the same time: not least, encouraging circularity processes in the construction and infrastructure sectors, boosting compliance with CAM (Minimum Environmental Criteria) with significant advantages for Green Public Procurement. The research in progress have recently been enriched by new directions, aimed at the reuse of dredging silts from hydroelectric basins. The results of these research are meeting the favour of many Italian productive activities in different regions, since the methodology and the application results are transferable in different territorial contexts.