中文摘要：

为研究运梁小车负重行走时结构的动力学行为以验证节段纵移悬拼法的可行性，并进一步评估运梁系统的合理性和安全性，结合北盘江大桥进行了足尺模型试验。足尺模型试验由支撑系统、运梁系统及起吊系统组成，其中支撑系统由6组钢管柱组成，每组设置2道挑梁，挑梁与弦杆外拼接板销接以抬起钢桁梁，运梁系统由轨道梁、扁担梁、对拉螺纹钢等组成，试验共设置4台运梁小车，通过小车行走实现节段纵移。同时，基于车一桥耦合系统动力分析基本理论，建立了运梁小车一轨道系统一试验既有结构大系统动力学方程，计算中阻尼采用Rayleigh阻尼，并计入轨道不平度效应，利用Newmark积分法进行耦合效应分析。结果表明：运梁小车运行平稳，最大加速度及动应力较小，运梁系统的设计合理，该工艺安全可行；运梁小车高速挡行走时轨道梁测点加速度峰值较低速挡有明显增大，但轨道梁应力峰值较低速挡增大不显著，其中实测加速度幅值为低速挡的1．51倍，实测最大动应力为低速挡的1．03倍；理论计算值与试验测试结果吻合较好，轨道梁、下弦杆测点理论加速度幅值约为实测值的94％，轨道梁理论动应力峰值约为实测值的96％，实测加速度及应力时程曲线与理论分析规律一致，验证了理论计算的正确性，可以为实桥应用研究提供理论基础。

英文摘要：

In order to investigate the dynamical behavior of structure when loaded transport vehicles walk so as to verify the feasibility of sectional longitudinal transport and cantilever installation method, and assess the rationality and security of transport system, the full-scale model test was conducted based on Beipan River Bridge. The full-scale model test consisted of support system, transport system and lifting system. The support system was made of 6 groups of steel pipe column with 2 cantilevering beams for each group, and cantilevering beams were connected with out splice plate so that support system can raise the steel truss beam. The transport system included track beams, C-beam and steel bars, where 4 transport vehicles were set in the test, and sectional longitudinal transport of the vehicles walking was achieved. Meanwhile, based on basic dynamic analysis theory of vehicle-bridge coupling system, the system dynamics equation of transport vehicle-track system-existing test structure was set up. Rayleigh damping was used as damping parameter and cooperated into the track unevenness effect. Then Newmark integral method was used to solve the coupling effect problem. The results show that the transport vehicles move smoothly, and the maximum acceleration value and dynamic stress are relatively small, which indicates that the design of girder transport system is rational, and this technique is feasible and safe. The peak acceleration of track measure point when transport vehicle walks in high gear is remarkably larger than that when transport vehicles walk in low gear, but its peak stress increases insignificantly than that in low gear. The actual acceleration amplitude walking in high gear is 1.51 times bigger than that walking in low gear, and the actual peak stress walking in high gear is 1. 03 times bigger than that walking in low gear. The theoretical calculated values well correspond with the tests measuring results. The theoretical acceleration amplitudes of measured points of track beam and lower chord