Evaluating the protecting effects of two consolidants applied on Pietra di Lecce limestone: A neutronographic study

In this work a combined laboratory-based and neutronographic investigation was carried out on a type of limestone, known as Pietra di Lecce stone, widely used in Italian Baroque as construction material. The limestone was treated with two different commercially-available coatings, namely nanosilica and nanolime, and artificially weathered by salt crystallization and temperature/relative humidity jumps. The aim was to provide an experimental evidence of the protective and consolidating effectiveness of the two treatments by looking at the water absorption process occurring inside the pore network of the analyzed stones. The analysis of the wetting front position revealed significant variations in the water absorption kinetics among the investigated samples, suggesting different mechanisms of interaction between the inorganic consolidants and the underlying bulk stone. Finally, a quantitative evaluation of the best effectiveness of the two products was addressed, particularly useful in view of an appropriate choice of restoration procedures to be applied to building materials.