In this thesis, based on the calculations of the total evacuation time, we analyze the impact of combustion products and the physical characteristics of the building users and their behavioral patterns on the safe egress time in a fire event.
The first part of the thesis summarizes the theoretical foundations that represent the starting point for the experimental work. In this part the fire hazards of high-rise apartment buildings, the basics of fire safety design and computer modeling of fire and evacuation scenarios are presented. In the thesis, we consider an existing high-rise apartment building. The parameters of the users of the building in question are defined based on gender and are divided into age groups, to which we define height, shoulder width and speed of movement. In the experimental part, we perform a computer simulation of a fire scenario in two height levels of the building. We continue with the modeling of evacuation scenarios, in which we also include the results of the computer simulation of the fire scenario. This is followed by a presentation, which is illustrated with diagrams or a 3D visualization and interpretation of the output data of the experimental work.
In carrying out the experimental work, we proceed from the three hypotheses of our thesis. By performing a computer simulation of a fire scenario in two levels of the building and modeling evacuation scenarios, we confirm two out of three hypotheses. By carrying out evacuation modeling, we find that the classification of the considered building, in which the users sleep and are divided by housing units into groups with close social ties, affects the total time of safe egress. When comparing the results of modeling individual and group evacuations of the users of an individual residential unit, we notice longer total times of egress for groups. This can be attributed to the way users move, as they do not move far from each other and thus affect the density of users in the room, as well as to the adjustment of speed to the slowest member of the group. We further confirmed that the level of fire protection of the building, which is evaluated by determining the time before the start of egress, significantly affects the total time for a safe egress from the building. When performing the simulation, the total time for a safe egress from the building is twice as long in the case of an inadequate working reporting and alarming system, or in the event that the system is not installed in the building at all compared to a properly functioning notification and alarm system. Finally, we refuted the hypothesis that in the case of a simulated fire event on the 4th floor, the total time for a safe retreat is longer by a factor of 1.2 compared to the simulated fire scenario on the 11th floor. By carrying out the evacuation scenarios, we confirmed that the total time for a safe retreat is longer if we simulate a fire scenario on the 4th floor, but by a smaller value than predicted by the hypothesis, namely by a maximum of 15%. Based on the experimental results of fire and evacuation scenarios, we have proposed measures based on currently valid guidelines and research findings. The proposed measures include the installation of connected smoke detectors in the stairwell and residential units, the partial division of the building into fire sectors, and the implementation of regular practical training for conducting evacuation from the building in the event of a fire. The measures are then sensibly evaluated in terms of time and price.
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