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Tobias Rupprecht

Publications and source records attributed to Tobias Rupprecht.

4 recordsLinked to original sources
arXiv2012

Empirical study of turning and merging of pedestrian streams in T-junction

Agent-based models are becoming indispensable tools in building design, safety assessments as well as management of emergency egress. However, reliable calibrations of these models should be mandatory before they are used in practice. To improve the database for model calibration we present results from two experiments at a T-junction and a corner. In such structures the dynamics of pedestrian streams is complex and up to now not studied systematically. To understand it deeply, series of well-controlled laboratory experiments are conducted. The Voronoi method, which is used to analyze the experiments, allows high resolution and small fluctuation in time and space. From the results, it is found that the fundamental diagrams of pedestrian flow in T-junction are not the same before and after merging. At the same density, the velocities of pedestrians before merging are smaller than that after merging. To analyze whether turning or merging of the stream is responsible for this discrepancy, we compare the fundamental diagrams of pedestrian flow in T-junction with the flow at a single corner. The fundamental diagrams of the streams in front and behind the corner agree well and are also in accordance with that from T-junction flow after merging. Besides, space-resolved measurements for the density, velocity profiles are obtained using Voronoi method. These maps offer important information about dangerous spots and thus enable to improve egress management and facility design.

physics.soc-ph↗
arXiv2011

Microscopic insights into pedestrian motion through a bottleneck, resolving spatial and temporal variations

The motion of pedestrians is subject to a wide range of influences and exhibits a rich phenomenology. To enable precise measurement of the density and velocity we use an alternative definition using Voronoi diagrams which exhibits smaller fluctuations than the standard definitions. This method permits examination on scales smaller than the pedestrians. We use this method to investigate the spatial and temporal variation of the observables at bottlenecks. Experiments were performed with 180 test subjects and a wide range of bottleneck parameters. The anomalous flow through short bottlenecks and non-stationary states present with narrow bottlenecks are analysed.

physics.soc-ph↗
arXiv2007

New insights into pedestrian flow through bottlenecks

Capacity estimation is an important tool for the design and dimensioning of pedestrian facilities. The literature contains different procedures and specifications which show considerable differences with respect to the estimated flow values. Moreover do new experimental data indicate a stepwise growing of the capacity with the width and thus challenge the validity of the specific flow concept. To resolve these differences we have studied experimentally the unidirectional pedestrian flow through bottlenecks under laboratory conditions. The time development of quantities like individual velocities, density and individual time gaps in bottlenecks of different width is presented. The data show a linear growth of the flow with the width. The comparison of the results with experimental data of other authors indicates that the basic assumption of the capacity estimation for bottlenecks has to be revised. In contradiction with most planning guidelines our main result is, that a jam occurs even if the incoming flow does not overstep the capacity defined by the maximum of the flow according to the fundamental diagram.

physics.soc-ph↗