Heat and moisture transfer through a steel stud gypsum board assembly exposed to fire

An assembly of gypsum boards fixed along their centre to a steel stud with a cavity between its two facings has been subjected to the standard fire of ISO 834. A model was developed to simulate the temperature evolution in the assembly measured at different distances from the fireside. Using measured thermal properties as functions of temperature, in combination with models taking into account radiation and convection in the wall cavity as well as mass transfer inside the gypsum boards led to a fairly good reproduction of the measured data. The fire tests were stopped immediately after the exposed gypsum layer showed ablation, which happened shortly after 60 min of exposition.