基于实际影响线的移动车辆过桥动力放大系数计算方法  

A calculation method for moving vehicle induced bridge dynamic amplification factor based on influence line

作　　者：王宁波[1] 周逸 周德[1] WANG Ningbo;ZHOU Yi;ZHOU De(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2020年第7期1853-1861,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51508576,51478472);国家重点研发计划项目(2017YFB1201204)。

摘　　要：通过分析现有桥梁动力放大系数(DAF)计算方法的特点和不足,提出一种基于实际影响线的DAF计算方法。首先,从移动车辆荷载作用所致的桥梁动力响应中提取桥梁测点实际影响线;然后,引入轮胎-路面接触力分布模型,结合车轴信息并采用影响线叠加重构桥梁准静态响应;最后,提取桥梁最大静力响应并以此计算DAF。开展移动车辆过桥数值仿真,对比研究波峰-波谷法、低通滤波法和本文基于实际影响线DAF提取方法对桥梁最大静力响应及DAF的计算差异。研究结果表明:基于实际影响线重构法提取的桥梁最大静力响应恒定,行车速度和路面状况的改变对车辆作用下桥梁最大静态响应值提取无影响,与实际情况相符;与现有桥梁动力放大系数计算方法相比,本文方法所得DAF更加精确、合理可靠。The characteristics and disadvantages of the existing bridge dynamic amplification factor(DAF)calculation methods were analyzed, and a new DAF calculation method based on the influence line information of bridge structures was proposed. Firstly, the actual influence line of the measurement point on bridge was extracted from the dynamic response excited by a passing vehicle. Then, a numerical model of the tire-pavement contact force distribution and the axle information of the passing vehicle were introduced in the influence line to reconstruct the quasi-static response of the bridge. Finally, the maximum static response was extracted from the reconstructed curve to calculate the DAF. Numerical simulation of the vehicle-bridge model was conducted to compare the difference of the maximum static responses and the DAF based on the peak-valley method, low-pass filtering method and the proposed method. The results show that the maximum static response obtained by the proposed method in the paper is stable and not affected by the vehicle velocity and road conditions. Compared to the existing bridge DAF calculation methods, the influence line based method proposed in the paper is more accurate, reasonable and reliable.

关 键 词：动力放大系数 准静态响应 响应重构 桥梁影响线 

分 类 号：TV45[水利工程—水工结构工程]