摘要
针对连续梁桥传统加固方法的不足,提出一种矮塔斜拉体系加固连续梁桥的方法。为研究拉索张拉方案对预应力混凝土箱梁的影响,以某座跨径为(60+96+60)m的三跨受损连续梁桥为例,建立有限元模型,对原桥进行预应力损伤敏感性分析;并根据最不利损伤状态,采用矮塔斜拉体系方法对损伤桥梁进行加固,对比分析两种不同拉索张拉顺序对加固过程中主梁挠度和应力的影响。结果表明:在加固过程中,两种张拉顺序下的主梁应力均未超过规范限值;从短索向长索张拉顺序下的主梁挠度变化更平缓,且截面应力变化更均匀;从长索向短索张拉顺序下的边跨跨中截面下缘压应力储备减小,接近拉应力限值,墩顶截面和跨中截面应力变化幅值较大,对结构受力不利。实际工程中应优先考虑从短索向长索的张拉顺序,可提高加固过程的安全性与经济性。
Aiming at the shortcomings of the traditional reinforcement methods for continuous girder bridges,a method of reinforcing continuous girder bridge by the extradosed cable-stayed system is proposed.In order to study the influence of the tensioning scheme on prestressed concrete box girders,this paper takes a three-span damaged continuous girder bridge with a span of(60+96+60)m as an example,establishes a finite element model,and carries out a sensitivity analysis of prestressing damage on the original bridge.According to the most unfavorable damage state,the extradosed cable-stayed system method is adopted to reinforce the damaged bridge,and the effects of two different tension cable tensioning sequences on the deflection and stress of the main girder in the reinforcement process are compared and analyzed.The results show that the stresses of the main girder under the two tensioning sequences do not exceed the specification limits in the reinforcement process.
作者
武兆夏
赵如
陈富琨
张文学
WU Zhaoxia;ZHAO Ru;CHEN Fukun;ZHANG Wenxue(Department of Urban Construction,Beijing University of Technology,Beijing 100124,China;China Railway Construction Kunlun Investment Group Co.,Ltd.,Chengdu 610040,China)
出处
《国防交通工程与技术》
2023年第6期24-29,14,共7页
Traffic Engineering and Technology for National Defence
