目录

为深化对钢管混凝土桥塔的认识,推动钢管混凝土结构在缆索承重桥梁桥塔中的应用,首先对钢管混凝土桥塔的工程应用情况及其一般构造进行了梳理,讨论了目前钢管混凝土桥塔设计中存在的主要问题,从构造简单、施工高效的角度对现有钢管混凝土桥塔构造进行了优化。而后对钢管混凝土桥塔钢壁板的局部屈曲性能及塔柱的力学性能研究进展进行了评述,并给出了推荐的设计方法。最后通过与传统钢筋混凝土桥塔和钢桥塔的对比,分析了钢管混凝土桥塔的技术特点和经济性。结果表明:由于对钢与混凝土共同承载机理认识不够深入、受混凝土单侧约束钢板的局部屈曲理论研究相对薄弱、钢混界面传力性能不明确等问题,导致目前钢管混凝土桥塔的构造过于复杂,施工高效性较差;构造优化后的PBL加劲型钢管混凝土桥塔的加劲构造、钢混连接构造更加简洁,钢壁板对混凝土的约束效应更强,无需配筋设计,能够节约用钢量、简化钢结构制造流程及现场安装工序,提高桥塔的工业化制造及装配化施工水平;考虑局部屈曲影响的加劲钢壁板构造设计方法和钢管混凝土桥塔承载力计算方法更加安全、合理;钢管混凝土桥塔具有设计灵活性、施工高效性和承灾高韧性,建设成本及养护成本远低于钢桥塔,在经济性上与传统钢筋混凝土桥塔可展开竞争,具有广阔的应用前景。

Progress in the Application of Research on Concrete-filled Steel Tubular Bridge Towers

To widen our understanding of concrete-filled steel tubular (CFST) bridge towers and promote the application of CFST structures in cable-supported bridge towers, the engineering applications and general structure details of CFST bridge tower were first sorted out. The main problems existing in the design of CFST bridge towers were discussed, and the existing CFST bridge tower structure was optimized from the perspective of structure simplification and construction efficiency. Subsequently, the local buckling behavior of steel panels and the mechanical properties of CFST towers was reviewed, and the recommended design methods were provided. Finally, the technological characteristics and economy of the CFST bridge tower were compared with those of the traditional reinforced concrete bridge and steel bridge towers. The results showed that owing to the lack of an in-depth understanding of the common bearing mechanisms of steel and concrete, the relatively weak research on the local buckling theory of steel plates is subject to unilateral concrete restraints, unclear force transfer performance for the steel-concrete interface, complexity of the current structure of the CFST bridge tower, and poor construction efficiency. The optimized PBL-stiffened CFST bridge tower has a simpler stiffening structure, a steel-concrete connection structure, and steel panels that have a stronger restraint effect on the concrete without the need for reinforcement design; thereby reducing steel consumption, simplifying the steel structure manufacturing process and on-site installation process, and improving the level of industrial manufacturing and assembly construction of bridge towers. A structural design method for stiffened steel plates that considers the influence of local buckling and the calculation method of the bearing capacity of the CFST bridge towers is safer and more reasonable. CFST bridge towers have design flexibility, construction efficiency, and high disaster-bearing toughness. The cost of construction and maintenance is much lower than that of steel bridge towers, and it can economically compete with traditional reinforced concrete bridge towers, which has broad application prospects.