Use of Autoclaved Aerated Concrete Walls for Deep Building Renovation

Autoclaved Aerated Concrete (AAC) is becoming a widespread construction material, being widely used either as a structural material for new masonry buildings or for infill walls. Given that a relevant share of the existing EU building stock needs both seismic and energy upgrading, the latter usage was here investigated. This paper proposes a deep renovation strategy for Reinforced Concrete (RC) framed buildings based on the replacement of the external layer of their double-leaf infill walls with AAC blocks panel. The contribution to the seismic resistance of the new AAC infills involves the highest improvement for the damage limitation limit state, while lower upgrades are achieved for near-collapse limit state. Moreover, the energy demand can be reduced by around 10%, just by replacing the outer layer of blocks, while a greater upgrade can be reached by adding an external insulation layer. Finally, this retrofit strategy can be implemented operating mainly from the outside, thus reducing occupants’ disruption during the renovation works.