中文摘要：

为了科学合理地确定波形钢腹板PC简支箱梁桥的动力冲击系数，依据标准车辆的车轮与桥面的接触关系建立了车一桥系统耦合振动的动力方程。在考虑路面平整度随机激励的作用下，运用MATLAB软件编写了车桥耦合系统动力方程的求解程序，求得了波形钢腹板PC简支箱梁桥结点位移的振动响应，并进一步计算出了该桥型动力冲击系数的数值解。将求得的数值解与现行《公路桥涵设计通用规范》（JTGD60—2015）中动力冲击系数的规范值和文中提出的波形钢腹板PC简支箱梁桥基频计算公式求得桥梁基频后获取的动力冲击系数进行对比分析。结果表明：在路面平整度为中的情况下，按照文中提出的波形钢腹板PC简支箱梁桥基频计算公式在获取桥梁基频后求得的动力冲击系数，与JTGD60—2015规范中采用有限元法获取桥梁结构基频后求得的动力冲击系数以及与车桥耦合振动数值模拟获得的动力冲击系数值吻合良好，而与JTGD60—2015规范中给出的简支梁桥基频估算公式获取桥梁基频后求得的动力冲击系数有较大差异。

英文摘要：

As a new type of steel-concrete composite structure, the pre-stressed concrete （PC） box-girder bridges with corrugated steel webs（CSWs）have been widely used in bridge engineering all over the world because of their excellent mechanical performance and light weight. Research on the dynamic response and dynamic impact factor （IM） of this new structure are limited, and no standard file has yet been established. In order to determine the IMs of the simple supported PC box-girder bridges with CSWs scientifically and reasonably, the two systems of motion equations for the vehicle and bridge are coupled through the contact condition between the vehicle wheels with bridge deck. Considered the random excitation effects of road surface pro- file, the vibration responses of the bridge nodes can be obtained by using the MATLAB program to solve the dynamic equation of vehicle-bridge system and the IMs of simple supported PC box girder-bridge with CSWs can be obtained. The obtained nu- merical IMs are compared to IMs obtained from the General Specifications for Design of Highway Bridge and Culverts JTG D60-2015 and IMs based on the formula of fundamental frequency proposed by the author. The results show that under the av- erage road surface conditions, the IMs calculated using the proposed formula of fundamental frequency are in good agreement with IMs based on the fundamental frequency calculated by the finite element method suggested by the JTG D60-2015 and the IMs from numerical simulations, while have significant differences with the IMs calculated using estimation formula of the fundamental frequency suggested by the JTG D60-2015. The conclusions can provide a good reference for dynamic response analysis and determining the dynamic impact factors of PC box-girder bridges with CSWs.