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In this study a simple speed-based model is employed to simulate an experiment of pedestrian bottleneck flow. The experiment revealed that the density near the bottleneck is influenced by the motivation of the pedestrians and the corridor width. In narrow corridors, distinct lanes are formed for pedestrians with low motivation. These lanes can disappear when the pedestrians have a high motivation to reach their target. We show that a speed-based model is - despite its relative simplicity- capable to reproduce the observed phenomena to a high degree.

Pedestrian behavior tends to depend on the type of facility. The flow at bottlenecks, for instance, can exceed the maximal rates observed in straight corridors. Consequently, accurate predictions of pedestrians movements in complex buildings including corridors, corners, bottlenecks, or intersections are difficult tasks for minimal models with a single setting of the parameters. Artificial neural networks are robust algorithms able to identify various types of patterns. In this paper, we will investigate their suitability for forecasting of pedestrian dynamics in complex architectures. Therefore, we develop, train, and test several artificial neural networks for predictions of pedestrian speeds in corridor and bottleneck experiments. The estimations are compared with those of a classical speed-based model. The results show that the neural networks can distinguish the two facilities and significantly improve the prediction of pedestrian speeds.

This article studies clogging phenomena using a velocity-based model for pedestrian dynamics. First, a method to identify prolonged clogs in simulations was introduced. Then bottleneck simulations were implemented with different initial and boundary conditions. The number of prolonged clogs were analyzed to investigate the decisive factors causing this phenomenon. Moreover, the time lapse between two consecutive agents passing the exit, and the trajectories of agents were analyzed. The influence of three type of factors was studied: parameters of the spatial boundaries, algorithmic factors related to implementation of the model, and the movement model. Parameters of the spatial boundaries include the width and position of the bottleneck exit. Algorithmic factors are the update methods and the size of the time step. Model parameters cover several parameters describing the level of motivation, the strength and range of impact among agents, and the shape of agents. The results show that the occurrence of prolonged clogs is closely linked to parameters of the spatial boundaries and the movement model but has virtually no correlation with algorithmic factors.

Lane formation in bidirectional pedestrian streams is based on a stimulus-response mechanism and strategies of navigation in a fast-changing environment. Although microscopic models that only guarantee volume exclusion can qualitatively reproduce this phenomenon, they are not sufficient for a quantitative description. To quantitatively describe this phenomenon, a minimal anticipatory collision-free velocity model is introduced. Compared to the original velocity model, the new model reduces the occurrence of gridlocks and reproduces the movement of pedestrians more realistically. For a quantitative description of the phenomenon, the definition of an order parameter is used to describe the formation of lanes at transient states and to show that the proposed model compares relatively well with experimental data. Furthermore, the model is validated by the experimental fundamental diagrams of bidirectional flows.

In recent years, numerous studies have been published dealing with the effect of individual characteristics of pedestrians on the fundamental diagram. These studies compared cumulative data on individuals in a group homogeneous in terms of one human factor such as age but heterogeneous in terms of other factors for instance gender. In order to examine the effect of all determined as well as undetermined human factors, individual fundamental diagrams are introduced and analyzed using multiple linear regression. A single-file school experiment with students of different age, gender, and height is therefore considered. Single individuals appearing in different runs are analyzed to study the effect of human factors such as height, age and gender and all other unknown individual effects such as motivation or attention to the individual speed. The analysis shows that for students age and height are strongly correlated and, consequently, age can be ignored. Furthermore, the study shows that gender has a weak effect and other nonmeasurable individual characteristics have a stronger effect than height. In a further step, a mixed model is used as well as the multiple linear model. Here, it is shown that the mixed model that considers all other unknown individual effects of each person as a random factor is preferable to the model where the individual speed only depends on the variables of headway, height, and all other unknown individual effects as fixed factors.

In this paper an overview of an open data archive with data from experiments investigating pedestrian dynamics is presented. As an example of the use of this data the analysis of recently published data about the capacity of crossings is shown.

The distribution of passengers waiting for a train is one of the limiting factors when improving the performance of a train station, as it heavily influences the boarding and alighting times of trains. We introduce a probability-based model for the pedestrians’ choice of a waiting position. Different factors as the geometry and the positions of other waiting pedestrians are taken into account. To assess the model, simulations on a simplified representation of a platform were used. The results of this simulation show good agreement with observations of previously conducted field studies.

In the simulation of pedestrian bottleneck flow with velocity-based models stable clogging could be observed, which is not in line with the movement of pedestrians in the real world. Four velocity-based models with different structures are selected in this paper to explore the cause of the phenomenon by identifying and analysing stable clogging. A series of simulations of pedestrians moving through a bottleneck are designed to investigate the decisive factors behind the unrealistic stable clogging, which includes the width of the exit, the flow of the pedestrian at the entrance and the size of the simulation time-step. The result of simulations with different models are compared and analyzed.

The reliable simulation of pedestrian movement is an essential tool for the security aware design and analysis of buildings and infrastructure. We developed HyDEFS, an event-driven dynamic flow simulation software which is designed to simulate pedestrian movement depending on varying routing decisions of the individual users and varying constraints. HyDEFS uses given density depending velocities to model congestions and evaluates flow distributions with respect to average and maximum travel time. This is of particular importance when considering evacuation scenarios. We apply HyDEFS on two small networks and cross validate its results by time-discrete and time-continuous calculations.

We present experiments on the behaviour of participants in front of a bottleneck. The waiting area was limited by a corridor of barriers leading straight to an entrance gate. We varied the width of the corridor and the degree of motivation of the participants to rush through the gate. We show that the density in front of the bottleneck grows with increasing corridor width and increasing motivation. Therefore, the velocity of individuals in the jam in front of the bottleneck is slower for wider corridors. Furthermore, it is shown that the flow through the bottleneck is controlled by the bottleneck width itself but is independent from the corridor width. The degree of motivation has, however, an influence on the flow rate through the bottleneck.

Assessing life safety by comparing the available safe egress time (ASET) and the required safe egress time (RSET) is a prominent task in performance-based fire safety design. The calculation of a safety margin by subtracting RSET from ASET is a straightforward concept and is easy to understand. However, when the concept was developed, fire and evacuation models only provided punctual information derived from experimental correlations or hand calculations. Nowadays, complex computer models for fire and evacuation dynamics have become state of the art. However, the ASET-RSET concept has not adapted to these developments. While uncertainties related to the model input and the model application are widely recognised, uncertainties emerging from analysing the output only play a subordinate role. Therefore, we introduce a map representation of ASET and RSET. The maps are generated by a spatial evaluation of the quantities used to determine ASET and RSET. Based on that, a difference map is introduced to represent the safety margin throughout the entire domain. Finally, a method is proposed to reduce the high information content of the difference maps to one scalar measure of consequences. This facilitates multivariate or risk-based analysis approaches and thus is able to reduce the uncertainties in performance-based design., This is a preprint version of the manuscript published in the Fire Safety Journal, which is referenced as DOI: 10.1016/j.firesaf.2020.103154.

While properties of human traffic flow are described by speed, density and flow, the locomotion of pedestrian is based on steps. To relate characteristics of human locomotor system with properties of human traffic flow, this paper aims to connect gait characteristics like step length, step frequency, swaying amplitude and synchronization with speed and density and thus to build a ground for advanced pedestrian models. For this aim, observational and experimental study on the single-file movement of pedestrians at different densities is conducted. Methods to measure step length, step frequency, swaying amplitude and step synchronization are proposed by means of trajectories of the head. Mathematical models for the relations of step length or frequency and speed are evaluated. The problem how step length and step duration are influenced by factors like body height and density is investigated. It is shown that the effect of body height on step length and step duration changes with density. Furthermore, two different types of step in-phase synchronization between two successive pedestrians are observed and the influence of step synchronization on step length is examined.