In this project, CUrisk was employed to assess and compare the risk-to-life due to fire in mid-rise and high-rise residential and office buildings of wood construction and of non-combustible construction and to demonstrate how fire protection measures can be tuned to ensure a mid-rise or high-rise building of wood construction is as safe as a similar building of non-combustible construction.
The computation results show that [...] Comparisons between the numbers of deaths and injuries of scenarios with and without suitable fire protection systems show the importance of fire protection systems in reducing life risk from fire in all buildings. Sustaining the reliability of fire protection systems through proper design, installation, inspection, and maintenance is important to achieve the life safety objectives.
This study which involves the development of fire loads and design fires for residential and non-residential mid-rise buildings is part of NEWBuildS’ “Rationalization o f Life Safety - Code Requirements fo r Mid-rise Buildings” project. The project is focused on analysing the code requirements that relate to fire resistance and the use of automatic sprinklers for mid-rise buildings built with combustible or non-combustible construction. The ultimate goal of the project is to come up with alternative solutions and, potentially, trigger changes in the code requirements for mid-rise buildings.
A review, compilation, and analysis of fire load survey data was conducted from available literature for residential and office buildings. A web survey of floor areas was also conducted for floor areas of mid-rise buildings. Fire loads and fuel packages for midrise buildings were developed based on previous surveys as well as the web survey. The fire load data in conjunction with statistical data was used to select fire scenarios from which design fire scenarios were chosen.
The fire characteristics of the selected fuel packages, such as heat release rate, and production of toxic gases, were analyzed using the two-zone fire risk analysis model, CUrisk, in order to develop appropriate design fires for mid-rise buildings.
To better evaluate failure of building elements and spread of fire beyond the room of fire origin, this thesis developed and integrated into CUrisk a barrier failure model and a fire spread model.
The role and position of the Fire Spread submodel were analyzed and changes to the system model and some other submodels were undertaken. With these modifications, CUrisk can employ the Fire Spread submodel to predict the fire hazard conditions in a building fire, and to use the results to predict the life risk and fire damages. Through a comprehensive case study of fire risk assessment of a six-storey residential building using the improved CUrisk, the Fire Spread submodel demonstrated the impacts of fire spread level on building occupant safety and fire losses.
The model performance was verified by comparing with the fire test measurements, which demonstrated good agreements. Comparable results are also predicted regarding the fall-off behaviour of the fire-exposed gypsum board as well as the charring behaviour. In addition, an example calculation was made using the probabilistic barrier failure model. Finally, a fire risk analysis case study was conducted on a six-storey apartment building with the purpose of showing the effect of wall barriers on fire risk. Results indicated that CUrisk can evaluate the impact of fire barriers on the fire risk with the new Barrie Failure submodel.