大轴重条件下既有铁路桥梁适应性分析及对策研究  

Research on Adaptability Analysis and Countermeasures of the Existing Railway Bridge under the Condition of Heavy Axle Load

作　　者：陈树礼[1,2] 许宏伟 刘永前 CHEN Shuli;XU Hongwei;LIU Yongqian(School of Safety Engineering and Emergency Management,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Provincial and Ministerial Collaborative Innovation Center of Large Infrastructure Performance and Safety,Shijiazhuang 050043,China;School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China)

机构地区：[1]石家庄铁道大学安全工程与应急管理学院,石家庄050043 [2]大型基础设施性能与安全省部共建协同创新中心,石家庄050043 [3]石家庄铁道大学土木工程学院,石家庄050043

出　　处：《铁道标准设计》2022年第11期69-76,共8页Railway Standard Design

基　　金：河北省重点研发计划项目(20375410D)。

摘　　要：为评价既有铁路常见跨度桥梁在大轴重运输条件下,安全储备和适应性,基于我国铁路设计标准和重载运输发展历程的系统总结和分析,采用数值模拟、工程应用实践和试验检测等手段,深入分析不同设计标准、不同跨度条件下,铁路桥梁在21~30 t轴重列车作用下的荷载效应和活载储备量,并结合工程实际开展桥梁结构重载化强化改造技术研究。研究结果表明:随着轴重增加,桥梁结构的荷载效应逐渐增加且活载储备量下降;25 t及以上荷载作用下,按照中-Z和中-活载荷载标准设计的小跨度梁活载储备量最低达到-23.97%,中等及以上跨度桥梁活载储备量最低达到-13.90%,结构安全储备存在一定程度不足;刚度偏低、强度偏小、稳定性偏弱和耐久性较差是既有铁路桥梁结构面临的主要技术问题;通过采用更换、加固、应用新型结构体系等强化改造措施,可整体提高结构承载能力和使用性能,满足大轴重运输要求。In order to evaluate the safety reserve and adaptability of common span bridges of existing railways under the condition of heavy axle load transportation, systematic summary and analysis of China’s railway design standards and the development process of heavy haul transportation are conducted. By means of numerical simulation, engineering application practice and test detection, this paper deeply analyzes the load effect and live load reserve of railway bridges under different design standards and different spans subject to the action of 21~30 t axle load trains, and carries out the research on the heavy load strengthening transformation technology of bridge structure in combination with engineering practices. The results show that with the increase of axle load, the load effect of bridge structure gradually increases and the live load reserve decreases. Under the load of 25 t and above, the minimum live load reserve of small span beams designed according to the medium-z and medium live load standards reaches-23.97%, and the minimum live load reserve of medium and above span bridges reaches-13.90%. Low stiffness, weak strength, low stability and poor durability are the main technical problems faced by the existing railway bridge structures. By adopting strengthening and transformation measures such as replacement, reinforcement and application of new structural system, the overall bearing capacity and service performance of the structure can be improved to meet the requirements of heavy axle load transportation.

关 键 词：大轴重运输 铁路桥梁 适应性分析 荷载效应 活载储备量 强化改造 

分 类 号：U239.4[交通运输工程—道路与铁道工程] U448.13[建筑科学—桥梁与隧道工程]