2017 Volume 82 Issue 739 Pages 2173-2183
When we design large scale sports facilities, we consult the architectural and fire-service regulations to secure evacuation safety. But these regulations define only the number, width or amount of evacuation facilities, such as path, exit, stairs, etc. And those regulations usually limit the flexibility of architectural design. For this circumstance, we propose the guidelines for design and management of evacuation crowd showing the process of actual design project of a large-scale stadium which holds 40,000 seats using multi-agent evacuation simulator. For this analysis, we validate fundamental relationship between density and velocity through the comparison with past observations and experiments to acquire the validity of generation of accumulation.
We mainly discussed three situations, replicating the process of actual design, and as the results, we clarified that the most of problems are stem from the accumulation of evacuees and its consecution. Therefore we proposed the design method and crowd management policy of not to generate the consecution of accumulations and where to generate / not to generate accumulations.
1. Evacuation from the spectator stands
1) To let evacuee flow out from the spectator stand, it is necessary not only arranging the width and allocation of exits, but also controlling the accumulation of evacuees at the concourse, especially not to generate the consecution of accumulation to the exit from the spectator stands.
2) Evacuation time from upper stand should be shortened to avoid smoke exposure and not to remain high place in high density which will cause fear.
3) On the other hand, lower stand where the pitch is shallow and where is little probability to smoke exposure, the policy to remain evacuees at the stand to avoid merge and accumulation on the evacuation route like stairs and concourse can be possible.
2. Merge and accumulation around stairs
High density accumulation on the stairs should be avoided not to cause falling over like dominos.
1) The most desirable policy is to prevent merge around stairs. But the plan or situation which will cause merge, the width of downstream stairs should be large to let evacuees flow to the lower part without generating accumulation. And installing physical guidance like handrails to avoid merge is preferable.
2) Generating accumulation of evacuees at safer place like plain concourse not to generate accumulation on the stairs where pitched and unsteady place.
3. Evacuation to / on the ground
1) Even there are a lot of spaces around the stadium, without letting precedent evacuees move to and stay the place far from the stadium, following evacuees cannot flow out there. Especially if the following evacuees remain on stairs, they will in unstable situation which will cause falling over like dominos.
2) If there are enough space, evacuees can stay safely around the stadium. But if there are not enough space around the stadium, guiding evacuees to keep walking on roads etc. and keeping them away from the stadium also can be reasonable guiding method. This guiding method has two main merit; one is that it is easy to control the direction of the evacuation and it is also easy to keep in low density of 1.0 persons/m2 which stem from free walking. To conduct this policy, all the evacuees are kept walking until all the evacuee finish evacuation from the stadium. This means that the first evacuee arrived at the ground is kept walking about the time of total evacuation time of the stadium.
