Thermal performance assessment of a clay hollow-brick masonry wall subjected to fire

Abstract

This work aims to analyse the thermal performance of a clay hollow‐brick masonry wall under a fire action referring to the standard time‐temperature curve (EN1991‐1‐2). For this fire exposure, temperature profile calculations underline the thermal response of certain wall configurations, while resulted temperatures of the non‐exposed surface can illustrate the thermal resistance in terms of the insulation criterion (I). For the aims of this study, a transient thermal model is utilized to assess the fire behaviour of the assumed wall assemblies. This paper introduces a full three‐ dimensional finite‐element analysis focused on heat transfer processes; in this regard, conductive, convective and radiative heat transfer mechanisms are assessed by adopting a finite element methodology (FEM) to cope with the geometry of the wall, the thermophysical properties of building materials and the prevailing environmental conditions. With respect to the thermal performance of the masonry wall subjected to fire, two sets of thermophysical property values of the clay material were examined. Accordingly, the influence of clay thermal conductivity and density variations were considered to deduce the thermal responsivity of masonry walls. In addition, a parametric procedure highlights the findings of a numerical study concerning the effect of low thermal emissivity coatings applied to hollow‐bricks cavity surfaces. Results of this analysis indicate the fire behaviour of masonry walls under elevated temperatures. The outcomes of this investigation exhibit a suitable approach to improve the overall fire performance of building elements under severe transient conditions.