Studie av dimensioners inverkan vid utrymning i spiraltrappor

Buildings should be designed so that evacuation can be done safely in case of fire or other cause would imply that the building must be evacuated immediately. A good option is the spiral staircase because they are both cheap, easy to install and space saving. The evacuation order is considered to be less suitable and should, according to Boverkets Byggregler, BBR, not be used as an escape route from an assembly hall or a hospital. Dimensions, materials, and if the stairs are moulded or free‐standing, are all parameters that could affect the walking on the stairs. The BBR today is not taking account of this specific, it is for all types of spiral staircases.The inception of this report has been to investigate how evacuation is affected by the width of a spiral staircase. By studying how the 28 test persons evacuate through three spiral staircases the differences in walking speeds, individual flows and the test subjects experience of the various stairs could be analysed. It also explores how the theoretical walking surface agrees with the actual walking surface and also how the evacuation of the group differs from the escape of an individual. A comparison between the results and the current regulations are discussed.The result showed that it was possible to overtake a person in front in the broadest of the threestaircases. It also showed that the actual walking surface was more than twice as big as the theoretical walking surface in all three staircases. Overall, the test group experience that it was easy to get down the stairs.In today's regulations it is determined that the spiral stairs should not be used as escape routes from assembly halls with a number of over 150 people at a prescriptive design. It does not mention that there are differences in the various types of staircases.This study has shown that it is possible to overtake a person in front in a spiral staircase if it is wide enough. Therefore further studies are proposed which examines were the limits for a narrow spiral staircase where people are forced to walk one after the other, and a wide spiral staircase where the opportunity to overtake the person in front exists. It is also proposed to investigate whether a handrail on the inside of the spiral staircase can affect the capacity of the staircase and also how the calculation of walking surface should be made of a spiral staircase.Validerat; 20150225 (cani