MODELLING OF STEEL TO TIMBER JOINT EXPOSED TO FIRE

Abstract

The paper presents an investigation on a timber joint with an inserted steel plate under fire exposure. According to standard EN 1995-1-2 (2004), the fire resistance of unprotected timber joints is limited to 30 min. However, several studies have shown that these joints can achieve higher fire resistance comparing to values given in the standard. In order to verify this, a numerical model of bolted steel-timber joint at elevated temperature was created. The presented model is focused on heat transport in the joint, which is affected by the presence of the steel plate and bolts. The model was validated on experimental results taken from literature and on measurement from a fire tests conducted in a medium-sized furnace. Considering the results of validation, the model has a good ability to predict residual cross-section, temperature of steel plate and bolts and temperature of timber elements. The results of validated numerical model are also compared to the analytical model.