Abstract：Increase in pedestrian density can lead to decrease in walking speed, and the first order component and its frequency of pedestrian loads. This can further change the variation law of structural vibration responses with increase in pedestrian number. Aiming at this problem, considering walking speeds varying under different crowd densities, introducing the existing empirical relationship to get the pedestrian’s step frequency under the corresponding walking speed, combining with the related test results to determine the corresponding spectral parameters of pedestrian loads, based on these the formula for the influence coefficient of pedestrian density were derived. The results showed that the structural vibration response increases with increase in the square root of pedestrian number when the crowd density is less than 0.3 persons/m2; after the crowd density is larger than 0.3 persons/m2, according to the ratio of the pedestrian’s step frequency to the structure’s frequency, there are two regions including the non-resonance region and the induced resonance region; in the non-resonance region, the growth multiple of structural vibration response is less than that of the square root of pedestrian number; in the induced resonance region, the change of the pedestrian’s step frequency may induce resonance, thus the growth multiple of structural vibration response is higher than that of the square root of pedestrian number.
陈海浪，宋志刚，张帅. 不同密度人群行走作用下结构竖向振动响应分析[J]. 振动与冲击, 2018, 37(11): 189-194.
CHEN Hai-lang, SONG Zhi-gang, ZHANG Shuai. Vertical vibration response of a structure under different number pedestrians walking on it. JOURNAL OF VIBRATION AND SHOCK, 2018, 37(11): 189-194.
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