Simulation and analysis of individual trampling risk during escalator transfers

• A five-stage trampling model for individual pedestrians was proposed.
• Several scenarios were simulated to study the impacts of 4 key factors.
• The pedestrian traffic is the main factor that influences the trampling risks.
• A decrease in the picking-up duration decreases the trampling risks.
• The trampling risk is higher than the average risk if the pedestrian velocity is low.

A type of trampling process that is caused by picking-up activities during escalator transfers was studied in this paper. A five-stage trampling model for individual pedestrians was proposed, and the social force model was modified considering the transfer features. Several scenarios were simulated to study the impacts of 4 factors, namely, pedestrian traffic, escalator velocity, picking-up duration and pedestrian velocity, on trampling probability. The results show that pedestrian traffic strongly affects the trampling probability, with a positive correlation throughout all scenarios; the picking-up duration affects the trampling probability, with a negative correlation throughout all scenarios; lower pedestrian velocities can result in higher trampling probabilities if the picking-up duration is short; and the escalator velocity may also affect the trampling probability, but there are no general rules for all scenarios. Thus, the impacts of these 4 factors can be queued in descending order as follows: pedestrian traffic  >>  picking-up duration  >>  pedestrian velocity  >>  escalator velocity. Countermeasures can be employed according to the results to reduce trampling risks.