华南理工大学学报(自然科学版) ›› 2024, Vol. 52 ›› Issue (1): 26-37.doi: 10.12141/j.issn.1000-565X.220840

• 结构疲劳与损伤 • 上一篇    下一篇

连续钢梁SFRC组合桥面板的优化设计

徐晨1 许琴东1 孙旭霞2 吴用贤2 张玉彬3 徐艺1   

  1. 1.同济大学 土木工程学院, 上海 200092
    2.同济大学建筑设计研究院(集团)有限公司, 上海 200092
    3.兴泰建设集团有限公司, 内蒙古 呼和浩特 010000
  • 收稿日期:2022-12-31 出版日期:2024-01-25 发布日期:2023-06-07
  • 作者简介:徐晨(1982-),男,博士,副教授,博士生导师,主要从事组合结构桥梁研究。E-mail:xuchenprc@tongji.edu.cn
  • 基金资助:
    国家自然科学基金资助项目(51978501)

Optimal Design of Steel-SFRC Composite Deck of Continuous Steel Girder

XU Chen1 XU Qindong1 SUN Xuxia2 WU Yongxian2 ZHANG Yubin3 XU Yi1   

  1. 1.College of Civil Engineering,Tongji University,Shanghai 200092,China
    2.Tongji Architectural Design (Group) Co. ,Ltd. ,Shanghai 200092,China
    3.Xingtai Construction Group Co. ,Ltd. ,Hohhot 010000,Inner Mongolia,China
  • Received:2022-12-31 Online:2024-01-25 Published:2023-06-07
  • About author:徐晨(1982-),男,博士,副教授,博士生导师,主要从事组合结构桥梁研究。E-mail:xuchenprc@tongji.edu.cn

摘要:

为探究中大跨径连续钢梁钢纤维混凝土(SFRC)组合桥面板优化设计方法,研究结合SFRC组合板偏拉试验与数值模拟所得SFRC受拉开裂特性,依据现有连续钢梁构造特点,采用SFRC代替原设计中C50混凝土铺装,通过Abaqus建立SFRC组合桥面板钢箱梁节段模型进行参数分析,考察了SFRC板厚、钢顶板厚、配筋率对主梁抗弯刚度、钢结构应力影响的特点。在此基础上以主梁弹性抗弯刚度和关键截面应力为约束条件,以上部结构自重与材料成本为优化目标,对中跨50 m和80 m连续钢梁进行优化。最后依据变量优化结果,采用Midas建立考虑负弯矩区SFRC开裂的杆系模型来验证优化结果的合理性。结果表明:文中引入材料塑性损伤的有限元分析方法具有可靠性,所建立的SFRC裂缝宽度与受拉损伤因子关系可以表征SFRC开裂状态。连续钢梁上80~120 mm厚SFRC层参与受力后使主梁弹性抗弯刚度提升17%~24%,当SFRC裂缝宽度达0.20 mm时,主梁抗弯刚度折减13%~20%;钢顶板应力降低7%~12%,主梁负弯承载力无明显变化。增大顶板厚度与配筋率均可有效改善钢顶板应力。对SFRC层厚、配筋率、钢顶板与顶板加劲肋尺寸进行优化分析,结果表明:相比原设计,优化后的50 m和80 m SFRC组合桥面板连续钢梁用钢量分别降低13%与6%,上部结构自重分别减小12%与6%,材料的成本分别降低14%与9%,该优化设计流程与优化结果可为SFRC组合桥面板在连续钢梁中推广应用提供参考。

关键词: 钢纤维混凝土, 组合桥面板, 参数分析, 优化设计

Abstract:

In order to investigate the optimization design method of medium and large span continuous steel girder steel fiber reinforced concrete (SFRC) composite bridge deck, the study used SFRC to replace C50 concrete pavement in the original design, and established SFRC composite bridge deck steel box girder segment model by Abaqus for parameter analysis. And the influence characteristics of SFRC plate thickness, steel roof thickness and reinforcement ratio on the bending stiffness and steel structure stress of the main beam were investigated. The study is based on the cracking characteristics of SFRC obtained by the combination of SFRC composite plate partial tension test and numerical simulation and the existing continuous steel girder structural characteristics. On this basis, the main girder elastic bending stiffness and key cross-section stress were taken as the constraints, and the upper structural self-weight and material cost were taken as the optimization objectives to optimize the mid-span 50 m and 80 m continuous steel girders. Finally, based on the variable optimization results, Midas was used to establish a bar model considering SFRC cracking in the negative moment region to verify the reasonableness of the optimization results. The results show that the finite element analysis method of plastic damage introduced in the paper is reliable, and the relationship between the SFRC crack width and the tensile damage factor can characterize the SFRC cracking state. The 80~120 mm thick SFRC layer on the continuous steel girder increases the elastic bending stiffness of the main girder by 17%~24% after participating in the force; the bending stiffness of the main girder decreases by 13%~20% when the width of the SFRC crack reaches 0.20 mm; the stress of the steel roof plate decreases by 7%~12%, and the negative bending capacity of the main girder does not change significantly. Increasing the thickness of top plate and reinforcement ratio can effectively improve the stress of steel roof. Through the optimization analysis of SFRC layer thickness, reinforcement ratio, steel roof and roof stiffener size, compared with the original design, the optimized steel consumption of 50 m and 80 m continuous steel girders with SFRC deck panels is reduced by 13% and 6% respectively, the weight of the superstructure is reduced by 12% and 6% respectively, and the cost of the material is reduced by 14% and 9% respectively. The optimized design process and optimization results can be used for the design of the continuous steel girder in SFRC deck panels. The optimized design process and optimization results can provide reference for the popularization and application of SFRC composite bridge deck in continuous steel girder.

Key words: steel fiber concrete, composite bridge deck, parameter analysis, optimal design

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