The impact of thermal insulation on the vulnerability of hollow masonry walls under elevated temperatures

There is little doubt that masonry walls have, throughout the history of mankind, been a critical part of building construction. From this standpoint, the present study aims to unfold the thermal behaviour of masonry walls when subjected to the standard cellulosic curve prescribed in ISO 834. Particular attention has been paid on temperature variations that are intimately connected to insulation fire resistance. The investigation initially focuses on the vulnerability of clay hollow-brick masonry wall arrangements with a varying thickness and position of insulation. These parameters are shown to significantly affect the penetration of heat through walls. In addition, temperature-dependent relationships among thermophysical properties of a combustible and a non-combustible insulation material, are examined. Alongside this, the effect of volumetric mass density on thermal conductivity for two sets of masonry units has been also taken into account. At last, this work is extended to identify the heat storage capacity of masonry walls depending on the construction arrangement of materials which can affect compartment fire dynamics. Within this framework, a numerical technique has been implemented to realise a finite element analysis (FEA) with respect to this transient thermal problem. Computational simulations have been carried out by adopting a well-known FEA modelling program.