Modelling of pedestrian movement around 90° and 180° bends Bernhard Steffen, Armin Seyfried Jülich Supercomputing Centre, Forschungszentrum Jülich GmbH, Wilhelm-Johnen Strasse, 52425 Jülich, Germany Preprint of conference paper at Advanced research workshop on Fire protection and life safety in buildings and transportation systems Santander, Oct 15-17 2009 ABSTRACT For the planning of large pedestrian facilities, the movement of pedestrians in various situations has to be modelled. These include different densities and different usages, at least standard operation mode and evacuation. Many tools for pedestrian planning are based on cellular automata (CA), discrete in space and time. It is common experience that CA have problems with modelling sharp bends in wide corridors and especially with 180° turns as they are frequent in staircases. They tend to move the pedestrians to the innermost lanes far too strongly, thereby reducing the capacity. In the extreme, only a small fraction of the width will be used after the bend. There have been some remedies proposed, but a systematic investigation is lacking, and there is no accord on the causes of the problem. In the paper, we present a comparison of various implementations of CA - for treating 90° and 180° bends with different width. We compare different models for the static floor field which provides the persons orientation. We also indicate how a density dependant static floor field can give a much increased capacity while still allowing single walkers to cut corners. We test at which position the walkers are most likely to get stuck and relate this to differences between CA models and real-world behaviour. The behaviour in the model is compared with observation of people walking through a 90° bend in a corridor and walking down a wide staircase. It is shown that with a proper floor field, at least the average behaviour of people can be simulated. Capturing the fluctuations present in reality is beyond the capacity of the simple models investigated. INTRODUCTION The last century has seen a tremendous growth of the world’s population, together with an increasing concentration of the population in big cities. Therefore, the safe and effective organisation of pedestrian facilities has gained in importance, as the crowds gathering in one place (for ceremonies, entertainment, work or education) get more frequent and larger.