Combined seismic and energy retrofit of masonry structures

Italian existing building heritage largely involves unreinforced masonry structures. In last decades, a growing research focus is directed toward retrofit solutions that can simultaneously enhance seismic performance and improve energy efficiency. In line with this objective, the paper offers insight into partial outcomes of a laboratory test campaign, actually ongoing, on an innovative retrofit system. The proposed system involves a lightly reinforced concrete wall cast within expanded clay formwork blocks: owing to their design, these blocks allow for the integration of a high-performance insulation layer, enhancing thermal efficiency. The retrofitted wall is strategically connected to the existing masonry wall at the levels of the horizontal floors. The resulting system can be conceptualised as a parallel configuration of two walls: the existing wall primarily resists also to vertical loads, and the new reinforced concrete one is able to absorb part of the horizontal seismic action, relieving the existing wall too. The paper presents some preliminary results of the experimental ongoing tests on the combined system with a specific typology of masonry, and the calibration of numerical refined models useful for the optimization of the further tests and parametric analysis.