Bärförmåga vid brand i Br2-byggnader

Sammanfattning: An aim with this master thesis is to evaluate when, according to Swedish building code, design of structural fire protection can be carried out using a localized fire as the design fire, i.e. to determine when flashover is not likely. Another aim of the thesis is to examine how a structure is globally affected by a local failure due to a localized fire. One of the goals is to develop a method that obtains a probabilistic distribution of the maximum heat release rate in a building. Such a method would be able to provide input to whether flashover is likely or not and therefore would help in determining whether a localized fire can be used for fire design of building structures. The other goal is to evaluate how robustness of a structure can be achieved in the case of a failing structure element. The developed method allows for determining heat release rate that can be used in fire safety design of structural members using localized fires. A localized fire can produce high temperatures, which can decrease the structural elements load bearing capacity. This can result in a local failure that can induce a progressive collapse. Robustness, achieved either by segmentation or alternate load paths, can be countermeasures to prevent progressive collapse due to initial failures caused by localized fires.