This report summarises progress in the second year of this project. Significant progress has been made towards achieving the original objectives of the project. In addition, several other applications of fire models have been identified that would further the interests of the Canadian wood industry and so appropriate research was initiated.
An objective of this project was to identify wood-stud walls that qualify as being of fireproof construction in Japan. To be classified as fireproof construction, a wood-stud wall must pass the 1 + 3 test in which it is subjected to a one hour fire-resistance test and then must support its load for another 3 hours as the furnace cools. Attempts were made to revise WALL2D to model the response of walls during the heating and cooling phases of an arbitrary fire. The revised model was to be used to model the response of walls in the 1 + 3 test and in furnished house fire tests run in Kemano. However, it turned out to be a major revision to include a cooling phase in WALL2D, but revisions were made to model a heating phase of an arbitrary fire. This was sufficient to get good agreement with temperatures measured within walls in Kemano. Revision of WALL2D to model the 1 + 3 test has been deferred until 2004-2005.
The Japan 2 x 4 Home Builders Association and the Council of Forest Industries have identified, by testing, wood-stud walls and wood-joist floors that pass the 1 + 3 test. These assemblies have been granted Ministerial Approval as being of fireproof construction. It is therefore possible to build 4-storey wood-frame apartment buildings in high-density urban areas. Employing models to identify assemblies that pass the 1 + 3 test is now less urgent, but will continue as models may suggest ways to optimise assemblies meeting the 1 + 3 test.
Another objective of this project was to undertake performance-based design of a building as a showcase study. Carleton University is developing a model to evaluate fire safety designs for 4-storey wood-frame commercial buildings. The first building to be analysed is a wood-frame version of the Carleton Technology Training Centre. The Carleton University model does not yet model the response of the structure of the building. To supplement Carleton University’s efforts, Forintek will undertake performance-based design for fire resistance of a wood-frame version of this building in 2004-2005.
While the initial completion date for this project was to be March 2004, it was intended that if other applications of fire models were identified that would further the goals of the Canadian wood industry, the project would be extended. During 2003-2004, several new applications of fire models were initiated:
A fire resistance model developed jointly by Forintek the National Research Council Canada is being employed to estimate the impact on fire-resistance ratings of the load applied to wood-stud walls during a test. This information would be useful when quoting the fire-resistance ratings of Canadian assemblies in export markets where lower loads are applied during fire tests.
A collaborative venture has been initiated with Australian researchers to model fires in large compartments (found in non-residential buildings) and the resultant response of wood-frame walls.
Data generated in fire tests conducted in furnished houses in Kemano is being used to assess the ability of current fire models to predict fire development in these houses and to predict the performance of a variety of building assemblies. If the models do a good job, one would have increased confidence in applying fire models in a performance-based design environment.
To demonstrate the good fire performance of wood-frame assemblies, three fire tests were run for visiting Chinese fire experts. Fire models were used to design the experiments to ensure that wood-frame assemblies were selected that could withstand the fire exposures envisioned in the tests.