桥梁冲击系数理论研究和应用进展

为推动桥梁冲击系数理论和应用研究的进一步深入开展,从计算方法、理论与数值模拟、现场试验与测试3个方面系统梳理国内外公路、城市和铁路桥梁工程领域冲击系数(或动力系数)的研究进展,并探讨其不足和发展趋势.计算方法方面,从桥梁冲击系数的定义出发,详细阐述典型国家最新规范冲击系数表达式;理论与数值模拟方面,分析了车辆参数、桥梁...

State-of-the-art of Theory and Applications of Bridge Dynamic Load Allowance

To promote the theoretical development of bridge dynamic load allowance (DLA) and its application, a state-of-the-art review and the research progress of highway, municipal, and railway bridge DLA were summarized from three perspectives:calculation method, theoretical and numerical simulation analysis, field test study. The relevant shortcomings and development trends were also discussed. Bridge DLA calculation formulas in typical countries codes were elaborated according to the definition of DLA. In terms of theory and numerical simulation analysis, the effect of vehicle parameters, bridge parameters, deck roughness, track irregularity on DLA were analyzed. In the field test study, experimental methods, data processing methods, and DLA field test results were introduced. Results show that both highway bridge and railway DLA are derived by statistical regression analysis, but they have different provisions in different countries. In contrast, highway bridge DLA is relatively simple compared to railway bridge. The development of the finite element method and vehicle-bridge coupled vibration theory has made the numerical simulation of structural dynamic response more precise and efficient. Attention should be paid to the overall DLA of medium (or small) span bridges and the local DLA of long-span bridges, such as suspenders, cables, and other components. As several factors affect DLA and may be intertwined, it is necessary to conduct DLA field tests and statistical probability analysis of different structures, responses, and section positions. The DLA in the design code is not suitable for evaluating the dynamic performance of existing bridges. Moreover, a standard of the DLA field test and analysis technology must be established. Non-contact, anti-interference and high-precision DLA test technology are the most promising future development directions.