钢筋混凝土拱圈与劲性骨架接头构造力学行为研究

发布时间：2018-04-30 14:30

本文选题：钢筋砼拱桥 + 劲性骨架　；参考：《重庆交通大学》2015年硕士论文

【摘要】：当前,国内大跨度钢筋混凝土拱桥多采用悬臂拼装法或悬臂浇筑法施工,悬臂拼装施工法降低了对缆索吊装系统的要求,但施工完成的拱圈接头多、整体性差、易开裂、耐久性差。悬臂浇筑法施工的拱圈虽整体性好,但因悬臂段较长,线形难于控制,施工风险大,且对扣锚系统有较高要求。日本采用悬臂浇筑与劲性骨架组合施工法修建了多座大跨度钢筋混凝土拱桥,施工完成的主拱圈整体性好、线形易于控制、降低了对缆索吊装系统的要求,较全劲性骨架法可节省用钢量。本文依托工程采用悬臂浇筑与劲性骨架组合法施工(即从拱脚向拱顶方向采用挂篮悬臂浇筑,到达一定位置后,安装劲性骨架合龙成拱,再浇筑外包混凝土,形成钢筋混凝土拱圈)。采用组合法施工的钢筋混凝土拱桥,劲性骨架位于拱顶区段,且只能在有限的拱圈混凝土内锚固,在外包混凝土浇筑过程中接头混凝土与劲性骨架受力较全劲性骨架混凝土拱桥更为不利,是大桥设计的关键。为此,本文以依托工程为研究对象,开展钢筋混凝土拱圈与劲性骨架接头构造力学行为研究。本文主要研究内容如下:①依照依托工程施工设计图及施工流程图,开展了主拱圈施工阶段仿真分析。②依据主拱圈施工阶段仿真分析结果。进行了基于劲性骨架施工过程稳定性及基于接头抗剪力学性能的劲性骨架腹杆构造优化。③查阅了国内外有关型钢混凝土粘结滑移本构关系理论研究的成果,进行了依托工程混凝土拱圈与劲性骨架(型钢)接头的受力行为理论分析。④采用有限元软件ANSYS建立了考虑型钢混凝土粘结滑移的精细化接头实体模型,依据精细化接头实体模型计算结果,进行了接头型钢混凝土界面相对滑移长度分析、外包混凝土应力分布规律分析。验证了型钢预埋长度理论分析结果,提出了接头构造设计建议。⑤设计制作了接头轴向压力及剪力局部足尺试验模型,开展了接头在轴向压力及剪力作用下的实验研究,将接头试验结果与考虑型钢混凝土粘结滑移的精细化有限元模型计算结果进行了对比分析。
[Abstract]:At present, the cantilever assembly method or cantilever pouring method is used to construct the long-span reinforced concrete arch bridge in our country. The cantilever assembly construction method reduces the requirement for cable hoisting system, but the arch ring joints completed in the construction are many, the integrity is poor, and the cracking is easy. Poor durability. The arch ring constructed by cantilever casting method has good integrity, but because of the long cantilever section, the linear shape is difficult to control, the construction risk is high, and there is a high requirement for the anchoring system. In Japan, many long-span reinforced concrete arch bridges were constructed by the combination of cantilever pouring and rigid frame construction. The main arch ring completed in Japan has good integrity, linear shape is easy to control, and the requirements for cable hoisting system are reduced. Compared with the full stiffness skeleton method, the amount of steel used can be saved. In this paper, the cantilever pouring and stiffening skeleton combination method are used in the project (that is, the hanging basket cantilever is used in the direction from the arch foot to the arch top. After reaching a certain position, the rigid skeleton is installed to close the arch to form a arch, and then the concrete is poured out. Form reinforced concrete arch ring. In the reinforced concrete arch bridge constructed by combination method, the rigid skeleton is located in the section of the arch roof and can only be anchored in the limited arch ring concrete. The joint concrete and the stiffness skeleton are more unfavorable than the fully rigid concrete arch bridge during the pouring process of the outer concrete, which is the key to the design of the bridge. Therefore, the structural mechanical behavior of reinforced concrete arch ring and stiffened skeleton joint is studied in this paper. The main contents of this paper are as follows: 1. According to the construction design drawing and construction flow chart, the main arch ring construction stage simulation analysis .2 according to the main arch ring construction stage simulation analysis results. Based on the stability of the rigid frame construction process and the shear mechanical properties of the joints, the structural optimization of the rigid skeleton web members is carried out. 3. The results of the theoretical research on the bond-slip constitutive relationship of steel reinforced concrete at home and abroad are reviewed. In this paper, the mechanical behavior of concrete arch ring and stiffened frame (section steel) joint is analyzed theoretically. 4. The solid model of fine joint considering bond slip of steel reinforced concrete is established by using finite element software ANSYS. Based on the calculation results of refined joint solid model, the relative slip length of SRC interface is analyzed, and the stress distribution law of concrete is analyzed. The theoretical analysis results of the embedded length of section steel are verified, and the design suggestion of joint structure 5 is put forward. The local full-scale test model of joint axial pressure and shear force is made, and the experimental study of joint under axial pressure and shear force is carried out. The test results of joints are compared with the calculated results of fine finite element model considering bond-slip of steel reinforced concrete (SRC).
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U441;U448.22

【参考文献】