A novel crowd random loads model for pedestrians walking on footbridge

With modern footbridges becoming lighter and slenderer, the serviceability has gained more and more concern. For analyzing the vibration and evaluating the serviceability of footbridge, it is essential to give a proper model of loads induced by man, especially by crowd. At present, there are some models for crowd loads (e.g., Matsumoto’s model). In these models, a factor relating to the number of pedestrians is always introduced to multiply the amplitude calculated for single person. However, not only the amplitude but also the distribution, which is not considered in the present models, of the loads will effect on the dynamic response of structure. In addition, for crowd loads, it has strong stochastic nature including the distribution and the difference between pedestrians in the crowd. The walking parameters for single person of Chinese people are obtained by a walkway measure system, and the random characteristics of these parameters are analyzed. Then, a crowd random loads model is set up, in which the randomness of single pedestrian and the distribution of pedestrians on structure are involved. Finally, based on the model, the dynamic response of a footbridge under random pedestrians flow is analyzed by finite element method. According to the results, it is more near to real dynamic response situation of footbridge under crowd loads with the model and method introduced in this paper.