Stone-mortar compatibility: Thermo-hygric cycling induced aging of masonries polluted by salt.
Résumé
Volubilis is an archeological site of North Africa inscribed as a UNESCO World Heritage. The site is in an advanced state of degradation, partly because of the salt crystallization phenomenon that happened in the main building stone. These salts are transferred to the stone through incompatible mortars previously used on the site. In this paper, the compatibility of a restoration mortar is studied, by subjecting it to the salt crystallization phenomenon. Two mortars will be used: Orleans mortar, a new restoration mortar, and Volubilis mortar, the one currently used on the site. To that end, masonry prototypes (stone-mortar samples) were polluted with a saline solution of NaCl and subjected to artificial aging tests that reproduce accurately the climatic environment of the site.