Australia Standard AS5100 Structural Steel Arched Bridge Construction

Steel arch bridges come in various forms and can primarily be categorized based on the following dimensions:

    Classified by bridge deck location

        Deck type: The bridge deck is located above the arch ribs, with loads transmitted through the columns. This structure boasts good stability and offers a wide view, as exemplified by the Fenglai Daxi River Extra-large Bridge.

        Half-through type: The bridge deck is located in the middle of the arch rib, combining aesthetics and structural efficiency, such as the Chaotianmen Yangtze River Bridge.

        Through-type: The bridge deck is suspended beneath the arch ribs, with force transmitted through hanger rods, also known as "tied arch bridge". The architectural height is small, and the design is transparent. The bridge deck system can serve as a tie rod to balance the thrust, such as the Tuojiang Extra-large Bridge.

    Classification based on the presence or absence of thrust

        Thrust-bearing arch bridge: The thrust is directly borne by the abutment, which requires high foundation conditions.

        Non-thrust tied arch bridge: A powerful horizontal tie rod is installed at the arch foot to withstand thrust, while the substructure only bears vertical forces, providing greater adaptability.

    Classified by the form of the main arch section

        Steel truss arch: Consisting of steel rods forming a "truss", it boasts light self-weight and remarkable spanning capacity, making it the mainstream form of extra-large span steel arch bridges. Representative works include the CQCM Yangtze River Bridge (552 meters).

        Steel box arch: The main arch is of a box-shaped cross-section, featuring high torsional rigidity and a simple yet sleek design. It is widely used in China, with notable examples including the Shanghai LP Bridge.

        Steel-concrete composite arch: By filling steel tubes with concrete, it boasts high bearing capacity, excellent plasticity, and toughness, combining the advantages of both materials. A notable example is the Sichuan Hejiang Yangtze River Bridge.

    Other classification methods

        According to the shape of the arch axis, there are various options such as circular arcs, parabolas, and catenary curves, which directly affect the mechanical properties.

        According to the arrangement form of suspenders, there are parallel vertical suspenders, oblique suspenders, and net-like suspenders. The latter has better stress distribution and a more slender structure.

👍 Pros and cons: strength and beauty

        Excellent spanning capability: With its efficient compression structure, steel's high strength enables astonishing spans, such as the main span of the Fenglai Daxi River Extra-large Bridge, which reaches 580 meters.

        Elegant and versatile design: The sleek curves exude a strong artistic appeal, and through their combination, they can forge a distinctive architectural landscape.

        High material strength and light self-weight: It can effectively reduce the structural self-weight and save the workload of the substructure.

main challenges

        Great construction difficulty: The construction system undergoes frequent transitions, demanding extremely high levels of technology and precision.

        Relatively high cost: The cost of steel and the refined manufacturing and installation processes drive up the overall cost.

        High requirements for later maintenance: Steel structures need regular maintenance work such as anti-corrosion and painting.