Fire resistance of gypsum-sheathed stud walls with an embedded steel door: Validation of a numerical approach

In the present study fire resistance tests of gypsum-sheathed stud walls were carried out and a fire safety steel door was embedded within the wall to address the mechanical interaction in between. A numerical approach was proposed based on coupled computational fluid dynamics/finite element method simulations to predict the temperatures and deformation. Since the heat transfer within the porous materials of the wall is crucial for the structural analysis, the numerical approach considered the conduction, chemical reactions, water vapour transport/phase change and thermal radiation. This detailed consideration showed good agreement to measured data for the wall and the door. It was highlighted, that the deformation of the door was well predicted, however, in the vicinity of the connections between the door and wall (e.g. door lock and bolts), the deformation was under-predicted. This was caused by the damaged connections, which were not considered in the simulation. The same effect was found for the wall. Although the numerical model was able to calculate the deformation behaviour, the predicted values were under-predicted due to the neglected failure of the gypsum boards. Furthermore, the numerical model was able to show the gap formation between the door and the wall with high accuracy.