Abstract： Crowd jumping loads are regarded as the joint stationary stochastic process. With the proposed coherence function and the previous auto-power spectral density (PSD) model for individual jumping load, two cross-PSD models are respectively established for the case that the jumping persons have same and the case with different jumping frequency. The synchronous problem in crowd jumping experiment can be overcame by the 3D motion capture technology. The results were verified to be consistent with those by the force plate method. The distribution of the jumping frequency and the values of the coherence function parameters are obtained from the experimental data. Using the cross-PSD model, the auto-PSD and the root mean square value of the structural acceleration response are calculated by the stochastic vibration theory. The theoretical prediction results agree well with the measured results of the large-span floor, which demonstrates that the proposed cross-PSD model and the calculation method are reasonable and can be used to analyze the structural response induced by the crowd jump loads.
