【摘要】 为快速、准确评估拱桥吊杆振动冲击效应,提出一种基于连续动力监测数据的拱桥吊杆冲击系数快速估算方法。该方法以日常交通荷载作用下吊杆连续动力响应数据为基础,对实时冲击系数进行频次统计,得到标准日概率密度谱;采用车-桥耦合振动数值方法计算吊杆冲击系数,确定与之对应的标准日概率密度谱分位点,给出分位点合理取值建议,并以该分位点的实时冲击系数作为快速估算值。将该方法应用于一座刚性吊杆钢拱桥中,基于动应变监测结果,统计7根吊杆实时冲击系数概率分布,结合车-桥耦合振动数值计算结果进行分析,得到:日常交通荷载作用下,吊杆实时冲击系数概率密度曲线具有良好的稳定性,标准日概率密度谱合理;建议取实时冲击系数标准日概率密度谱上85%～90%分位点对应的实时冲击系数作为吊杆冲击系数快速估算值。更多还原

【Abstract】 In order to evaluate the dynamic impact effect of the hangers in arch bridge,a rapid estimation method based on continuous dynamic field measurement is proposed.The statistical standard daily spectrum of the real-time impact factor was acquired in statistical analysis that was carried out utilizing the continuous dynamic strain data from each test location on the hanger in the condition of regular daily traffic flow.Then numerical simulation of a three-dimensional vehiclebridge interaction system was applied to calculate the dynamic impact factors for each hanger.The calculation value was compared with the fractional point on the standard daily spectrum to determine the pick point.For the stable correspondence,a rational value of real-time impact factor corresponding to the pick fractional point was identified as the evaluation of impact factor of the hanger.A steel arch bridge with stiff hangers was applied as a case in this study.The presented method was verified with the field strain measurement from 7 hangers.The results show that the real-time impact factor values,which were acquired in the statistical standard daily spectrum at 85%-90%fractional point,have a stable consistency with the simulation IMs of hangers.更多还原