Timber Framed Walls Lined with Gypsum Plates Under Fire

Building regulations require fire rating for partition walls under standard fire exposure. New eco building solutions are becoming popular and, in particular, the light timber framed walls. The fire rating of this building element depends on fire testing. Finite element approximation can be used, when models are validated from previous experimental tests. This investigation presents the validation model from a full-scale assembly, using one gypsum board on each side and several solid timber studs. The charring rate in the wood studs is an important predictor for the fire performance of the wall and as well the temperature of the unexposed surface. This investigation also predicts the temperature field in other key points, such as the points located in interface between the studs and gypsum board, for the onset of charring. Finally, the fire resistance is also considered by means of the simplified method (improved model). This models seems to under predict and over predict the results. There is a good approximation between the numerical model (Hybrid –FEM) and the experimental test used for validation, which allowed for a parametric analysis, testing the variation of the gypsum thickness and the thickness of the cavity. The dimension increase of the wood stud does not provide almost any change on the fire resistance of the assembly (insulation), but provides significant modification on the residual area for load bearing capacity.

Timber Framed Walls Lined with Gypsum Plates Under Fire Conference Paper