Experimental study on pushing propagation in a dynamic Pedestrian Queue

Abstract

“Crowd shockwave” is a hallmark of high-density crowd disasters, yet its triggering and propagation mechanism in dense crowd dynamics remains insufficiently understood. This study extended small-scale pushing experiments from static to dynamic pedestrian queues to investigate whether and how movement parameters modulate forward propagation. In a controlled five-person queue, synchronized kinematic–mechanical data were collected using optical mocap system and flexible pressure-mapping clothing. At an interpersonal distance of 20 cm, a critical peak-force threshold of about 100 N is identified for forward propagation, with no material differences across movement states. Propagation speed is found as a function of the initial impulse, but both intercept and slope depend on movement. A unified propagation-speed equation is proposed and validated with forward-walking data. The findings deepen the understanding of crowd shockwaves, provide empirically grounded parameters for the optimization and validation of crowd models, and provides support for risk assessment and safety management in high-density crowds.