Sympathetic vibration due to co-ordinated crowd jumping

In assembly structures or places where crowds may gather such as dance halls, theaters, gymnasia and stadia, the loading is almost entirely caused by human activities. Structural resonance or near resonance and the resulting vibrations causing discomfort of spectators have often been observed during a rock concert or a sporting event. Recent research efforts have focused on developing load models to quantify the dynamic loading effects induced by individuals and groups up to 40 people. The lack of coherence of motion from a large crowd, the so-called ‘‘group effect’’, has been quantified based on simulations. The simulation results and the load models thus developed should be verified against actual field data from assembly structures before they are adopted into building codes and standards