Behaviour of non-metallic shear connections in fire

This paper presents a study of the fire performance of non-metallic timber connections comprising glass fibre reinforced polymer (GFRP) dowels and a densified veneer wood (DVW) flitch plate. Metallic shear connections are very common in timber structures, but can fail quickly in fire conditions due to the high thermal conductivity of metals. In this study the fire performance of a non-metallic connection constructed from phenolic GFRP dowels and a DVW flitch plate is studied numerically and experimentally. The numerical predictions are obtained with a structural model linked to different heat transfer models. Experimental validation of the heat transfer models is obtained by measuring the temperature in connections that are subjected to radiant heat and fire. In this test the heat flux is determined using thermal imaging. The numerical predictions of the structural model at elevated temperatures are validated with mechanically loaded connections, exposed to temperatures up to 620 °C. Digital image correlation is used to determine the displacements between the flitch plate and the timber during the tests. After validation, the model will be used to predict the behaviour of the non-metallic connection in a standard fire.