Project contact is Christian Dagenais at Université Laval
The structural elements of a building must provide fire resistance in order to prevent collapse and to provide an escape route for occupants. The basic philosophy is that components that support elements with a degree of fire resistance must also offer the same degree of resistance. It is also assumed that the connections between these elements provide at least the same degree as the supported elements. Traditionally, heavy timber construction used ingenious construction principles and assemblies made of cast iron. With the advent of innovative fasteners (eg self-tapping screws), the principles of assembly have changed greatly and are now similar to a metal frame. So, several studies have been carried out in recent years in order to increase knowledge of the fire behavior of these assemblies (Audebert et al., 2012, Dhima 1999, Frangi et al. 2009, Peng 2010, Ohene 2014, Ali et al. 2014 , Moss et al. 2008). Although a significant amount of information is available in the literature, it often indicates short-term flammability resistance (± 30 min), which is largely insufficient for buildings having to provide a degree of fire resistance of at least 2 hours. The objective is to carry out a literature review in order to fully understand the factors influencing the fire performance of assemblies in wood construction. A model of thermomechanical behavior and a simplified analytical approach would have to be developed.
With the arrival of innovative fasteners (e.g. self-tapping screws), assembly principles have greatly changed and now resemble a metal framework. Although a significant amount of information is available in the literature, it often indicates short-term flammability resistance (± 30 min), which is largely insufficient for buildings that need to provide a fire resistance rating of at least 2 hours. The objective is to carry out a literature review to understand the factors influencing the fire performance of assemblies in wood construction. A modeling of thermomechanical behavior and a simplified analytical approach should be developed. Testing from an intermediate furnace is likely to be required to validate model assumptions.
This paper describes numerical modelling to predict the fire resistance of engineered timber floor systems. The floor systems under investigation are timber composite floors (various timber joist and box floor cross sections), and timber-concrete composite floors. The paper describes 3D numerical modelling of the floor systems using finite element software, carried out as a sequential thermo-mechanical analysis. Experimental testing of these floor assemblies is also being undertaken to calibrate and validate the models, with a number of full scale tests to determine the failure mechanisms for each floor type and assess fire damage to the respective system components. The final outcome of this research will be simplified design methods for calculating the fire resistance of a wide range of engineered timber floor systems.