基于移动式冲击振动的桥梁快速测试与柔度识别研究进展

Recent advancements in mobile impact vibration-based bridge rapid testing and flexibility identification

如何实现公路网上大规模中小型桥梁的快速测试与状态参数识别是迫切需要解决的问题。结构检测监测技术是保障桥梁安全的重要手段,但传统检测技术费工费时、结构健康监测系统复杂昂贵,移动测试由于其具有高机动性、快速、低成本的优点在国内外得到广泛研究,为中小型桥梁的快速测试提供新思路。文章综述了移动式冲击振动测试方面的研究进展,对移动式冲击振动测试的理论基础、测试方法及柔度识别理论、软硬件系统和工程实践进行详细阐述。首先,阐述移动式冲击振动的桥梁快速测试思路,推导冲击振动测试数据与常规环境振动测试数据包含信息的本质区别,证明冲击振动测试数据具备识别结构柔度等详尽动力参数的独特优势;其次,综述基于冲击振动的桥梁快速测试方法及柔度识别理论,包括基于整体固定点冲击振动、分块移动式冲击振动和车载式连续冲击振动的结构位移柔度识别理论,以及基于冲击振动与长标距应变传感技术的应变柔度识别理论;然后,介绍基于冲击振动的桥梁快速测试软硬件一体化系统开发方面的研究进展;最后,综述移动式冲击振动测试在桥梁工程中的应用实践。文献综述表明:相比较于常规环境振动测试,移动式冲击振动测试能够实现边移动边激振,在方便快捷的同时具备识别桥梁振型缩放系数、模态质量、位移/应变柔度等详尽动力参数的优势,为公路网上数量众多的中小跨径桥梁病害快速筛查、损伤识别、可靠度评估与长期性能劣化研究奠定数据基础。

How to perform rapid testing and structural parameters identification of large number of middle and short span bridges in highway road network is a challenging problem.Structural inspection and health monitoring techniques are effective measures to ensure the safe operation of bridges, however, traditional inspection techniques are time-consuming and labor-intensive, and structural health monitoring system is expensive and complicated.The mobile testing technique is receiving much attention around the world because of the advantage of high mobility, rapid testing and low-cost, providing a new solution for rapid testing of middle and short span bridges.This paper summarized the recent advancements in mobile impact vibration testing, including the theoretical basis of mobile impact testing, rapid testing scheme, structural flexibility identification theory, hardware development and engineering applications.Firstly, the idea of mobile impact vibration based bridge rapid testing was introduced, and the relationship between Frequency Response Functions(FRF) estimated from ambient vibration testing data and those estimated from impact vibration testing data was investigated, revealing that the impact vibration test data has the unique advantage of identifying more meaningful structural parameters such as structural flexibility matrix. Secondly, the impact vibration test-based rapid testing scheme and structural flexibility identification theory were presented, including the displacement flexibility identification methodsbased on fixed point impact testing, mobile impact testing method, the continuous excited mobile impact testing method, and the strain flexibility identification theory based on impact vibration testing and long-gauge strain sensing technology. Thirdly, the research progress of hardware development for rapid impact testing of bridges was presented. Finally, typical case studies of the mobile impact testing for bridge rapid testing and structural identification have been summarized.It is found that the mobile impact testing method has the capability of identifying more meaningful structural parameters including modal scaling factor, modal mass and modal flexibility compared with the conventional ambient vibration testing.The identified results are important parameters for detecting structural defects/damages, evaluating structural reliability and investigating the long-term performance degradation of numerous bridges in road network.