A Novel Composite Reinforced Mortar for the Structural and Energy Retrofitting of Masonry Panels

Abstract

Existing masonry buildings become more and more outdated depending on the actual state of conservation, but also in relation to the renovation of the performance requirements stated in current code and guidelines. Therefore, two fundamental aspects emerge as drawbacks: mechanical resistance and thermal conductivity. The structural retrofitting often consists of a covering by means of Composite Reinforced Mortar (CRM), which involves a pre-impregnated fiber mesh into an inorganic binder (e.g. lime-based mortar), while an additional insulation layer is designed for thermal scope. In this study a new composite, concerning a fly-ash based geopolymer and a glass fiber mesh (namely Composite Reinforced Geopolymer Mortar - CRGM), is proposed. The goal is to demonstrate its ability of improving both the shear strength and the thermal resistance of a masonry panel (simulating an existing structure). At this scope, an experimental investigation put in contrast the proposal with respect to a traditional CRM-system (i.e. lime-based matrix and the same glass fiber mesh). The results confirmed the validity of the CRGM. Moreover, a theoretical simulation evidenced the potential impact of the CRGM on the commonly used types of masonry all around Italy from the thermal point of view.