Thermo-mechanical analyses of masonry structures in fire conditions

Historic masonry buildings are highly vulnerable to anthropic actions and environmental factors due to their low tensile strength, and bounded compressive strength. Over the years, numerous studies and experimental campaigns have been conducted to characterise the buildings’ response to external actions and identify solutions for their conservation against multiple factors, such as climatic changes, material ageing and earthquakes. However, the historic masonry structures’ response in case of fire and their safety assessment in post-fire conditions, still needs to be thoroughly investigated both from an experimental and numerical point of view. This paper generalises the constitutive equation of masonry-like (or no-tension) materials under non-isothermal conditions to the case in which the masonry has weak tensile strength and bounded compressive strength, even temperature dependent. The generalised constitutive equation is then implemented in NOSA-ITACA and the explicit solution to the equilibrium problem of a masonry circular ring in plane strain condition is calculated and compared with the numerical solution. Subsequently, the code is used to perform an uncoupled thermo-mechanical analysis of a real case study: a masonry barrel vault tested in fire conditions. The agreement between the experimental and numerical results paves the way for further study and research.