人群屈伸律动激励下的结构多模态振动反应谱OA

The classic design method for human-induced structural vibration response spectra fails to account for the coupling effects among different structural modes and the modal contributions of individual participants.It is therefore not suitable for structures with complex vibration modes or closely-spaced vibration modes.To address this issue,the present paper treats the structure as a multi-degree-of-freedom system and crowd bouncing as multi-point excitations.Based on stochastic vibration theory,a response spectrum prediction formula for the root-mean-square structural acceleration response is derived.Subsequently,by employing random field models,closed-form expressions for the single-degree-of-freedom dimensionless response spectrum,the correlation coefficients among different structural vibration modes,and the correlation coefficients among different bouncing individuals are derived,enabling efficient prediction of structural vibration responses.The predicted results obtained using the response spectrum method are compared with field-measured response data from large-span floors.The results demonstrate that the proposed response spectrum prediction method is valid and can be used for the design and assessment of human-induced structural vibration responses subjected to crowd bouncing loads.