Volume 36 Issue 9
Jan.  2022
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Hao Ding, Rui Li, Jing Mo, Xiaozhang Li, Di Liu. Study on Reinforcement of Steel Truss Bridge Based on External Prestressed Load Lifting[J]. STEEL CONSTRUCTION(Chinese & English), 2021, 36(9): 33-39. doi: 10.13206/j.gjgS21041601
Citation: Hao Ding, Rui Li, Jing Mo, Xiaozhang Li, Di Liu. Study on Reinforcement of Steel Truss Bridge Based on External Prestressed Load Lifting[J]. STEEL CONSTRUCTION(Chinese & English), 2021, 36(9): 33-39. doi: 10.13206/j.gjgS21041601

Study on Reinforcement of Steel Truss Bridge Based on External Prestressed Load Lifting

doi: 10.13206/j.gjgS21041601
  • Received Date: 2021-04-16
    Available Online: 2022-01-11
  • The concept of in vitro prestressing originated from France at the earliest and is one of the important branches of post-tensioning prestressing system, which usually adopts large-diameter steel bars, steel strands and high-strength steel wires as tension application tools to prestress the beams. This method can effectively reduce the stress level of the structure and can play the roles of reinforcement unloading and changing the internal force distribution of the structure, and at the same time can improve the load bearing capacity, crack resistance and stiffness of the structure. However, the in vitro prestressing method is less studied in reinforced steel truss structures, and the related theory is relatively lacking.
    In order to study the effect of in vitro prestressing with different number of strands on the strengthening of steel truss bridges, this paper takes a 128 m span under-bearing simply-supported steel truss bridge over the Omo River as the research object, and proposes three in vitro prestressing strengthening schemes for its load lifting analysis, and uses finite element software to establish the full bridge model with 7, 9, and 11 strands per beam respectively, and analyzes the strengthening of steel trusses in terms of rod strength, structural stiffness, fatigue, overall stability, and nodal plate stress distribution. The result analysis shows that:the stress of longitudinal beam, crossbeam, top chord and bottom chord gradually decreases with the increase of the number of strands, and the stress of the bars gradually improves; the number of strands increases, the deflection of the structure gradually decreases, the fundamental frequency gradually increases, and its stiffness continuously improves; with the increase of the number of strands used for reinforcement, the other strands, except for the longitudinal beam, gradually increase. With the increase in the number of strands used for reinforcement, in addition to the longitudinal beam, the fatigue stress amplitude of the rest of the rod is constantly reduced; the critical load factor is constantly increased, and the stability is increased; the area of the low stress area of the important parts of the node plate is increased, and the area of the high stress area and the secondary high stress area is reduced, and the number of screw holes in the potential tearing area is constantly reduced, and the probability of tearing damage of the node plate is reduced. However, as the number of strands increases, the axial force of the lower chord increases and the stability safety factor of the section decreases, so it is necessary to control the number of strands tensioned and limit the magnitude of load lifting.
    The results show that all the three in vitro prestressing reinforcement solutions can achieve the load lifting effect, and with the increase of the number of strands used, the structural strength, stiffness and stability are non-linearly improved, and the proportion of low stress distribution area of the node plate is gradually increased, and the bridge is reinforced by 11 single-steering bending line shaped in vitro prestressing strands, which is the most practical and reasonable reinforcement solution.
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  • [1]
    陈惟珍, 徐俊, 龙佩恒, 等. 现代桥梁养护与管理[M]. 北京:人民交通出版社, 2010.
    [2]
    李满来. 体外预应力加固桥梁转向块混凝土配置研究[J]. 世界桥梁, 2018, 46(4):88-91.
    [3]
    王元清, 胡宗文, 石永久, 等. 基于冲击韧性的钢结构厚板防止脆性断裂的选材方法[J]. 钢结构, 2011, 26(7):43-46.
    [4]
    张妮. 埃塞俄比亚奥莫河桥[J]. 世界桥梁, 2015, 43(2):89.
    [5]
    刘明才, 胡仲春, 谷守法, 等. 波形钢腹板特大桥体外预应力设计及应用研究[J]. 世界桥梁, 2017, 45(1):45-50.
    [6]
    张博. 结合有限元分析的钢结构桥梁检测与评估研究[D]. 重庆:重庆交通大学, 2018.
    [7]
    张爱林, 赵海明, 刘学春, 等. 在役铁路钢桁梁预应力加固研究[J]. 铁道标准设计, 2014, 58(12):76-80.
    [8]
    吴云贤. 面向特高压铁塔的Q420低合金高强钢焊接接头组织性能优化研究[D]. 杭州:浙江大学, 2014.
    [9]
    陈樑明. 基于智能预应力技术的简支钢桁梁受力性能研究[D]. 南京:东南大学, 2015.
    [10]
    AASHTO. AASHTO LRFD bridge design specifications[S]. Washington DC:AASHTO, 2017.
    [11]
    刘寒冰, 王龙林, 谭国金, 等. 预应力对体外预应力简支钢梁自振频率的影响[J]. 吉林大学学报(工学版), 2013(1):81-85.
    [12]
    程帅奇. 铁路中等跨度抢修钢梁疲劳性能研究[D]. 石家庄:石家庄铁道大学, 2017.
    [13]
    卢波. 桥梁加固与改造[M]. 北京:人民交通出版社, 2004.
    [14]
    刘来君, 赵小星. 桥梁加固设计与施工技术[M]. 北京:人民交通出版社, 2004.
    [15]
    陈惟珍. 钢桁梁桥评定与加固:理论、方法和实践[M]. 北京:科学出版社, 2012.
    [16]
    British Standard Institution. Steel, concrete and composite bridges part 2:specification for loads:BS5400[S]. London:The Board of BSI, 2006.
    [17]
    李运生, 王慧佳, 张彦玲. 钢桁梁桥高强螺栓连接的节点板局部受力性能分析[J]. 石家庄铁道大学学报(自然科学版), 2013, 26(3):1-7.
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