Structural Steel Tubular Truss

Structural steel tubular trusses are grid-based structures composed of steel pipe members connected at their ends to form a stable geometric configuration.These engineering solutions are characterized by their efficient use of materials,lightweight properties,and excellent load-bearing capacities,making them a preferred choice for a wide range of construction projects.

Key Features and Advantages

The notable advantages of steel tubular trusses include their favorable geometric characteristics and thin-walled design.The cross-sectional material is distributed evenly around the centroid,resulting in a large radius of gyration and enhanced torsional stiffness.As a consequence,these trusses exhibit superior performance as compression,bending,and biaxial bending members.

When compared to traditional open-section steel trusses(such as those using H-beams or I-beams),tubular trusses demonstrate better overall stability and higher load-bearing efficiency.They often eliminate the need for additional node plates,leading to simpler construction details.Furthermore,the closed section of the tubes offers inherent benefits,including reduced surface exposure(approximately 50-60%of open sections),which aids in corrosion protection and can lower coating material costs.

Applications in Modern Construction

Steel tubular trusses are versatile and can be adapted into various forms such as simply supported trusses,arches,frames,and towers.Their application is prominent in large-span public buildings and infrastructure projects.

Building Roof Structures:They are widely used in industrial plants,stadiums,exhibition centers,airport terminals,and commercial complexes due to their ability to achieve large spans with relatively low self-weight and material consumption.

Bridge Engineering:Notable examples of tubular truss applications in bridges include the Ya'an Ganhaizi Bridge and the Guangxi Pingnan Three Bridge in China,showcasing their suitability for heavy-load and long-span conditions.

Other Structures:They are also employed in pylons,large-span space structures,towers,and as frameworks for membrane structures and tent warehouses.

A Specialized Hybrid:Concrete-Filled Steel Tubular(CFST)Trusses

A significant development in this field is the trussed concrete-filled steel tubular(CFST)hybrid structure.This system typically features CFST chords(which are prominent members)and hollow steel tube webs.The synergy,or"hybrid effect,"between the concrete-filled chords and the steel webs allows them to work together effectively throughout the structure's life cycle.This hybrid approach offers enhanced stiffness,durability,and resistance,making it suitable for infrastructure subjected to harsh environments and heavy loads.China has even established specific technical standards,such as GB/T 51446–2021 and T/CECS 785–2020,to govern the application of these hybrid structures.

Fabrication and Design Considerations

The fabrication of tubular trusses often involves welding the members directly at the nodes,typically requiring precise profile cutting of the pipe ends where they intersect,as the connections usually involve welded intersecting joints.The design process must carefully consider factors such as the stability of compression members,joint eccentricity,and the static strength of the connections.Ongoing research continues to refine design methodologies,including the use of frame models for structural calculation and exploring optimized designs to minimize material volume while meeting all safety constraints.

In summary,the structural steel tubular truss stands as a testament to efficient and adaptable engineering.Its ability to combine material economy with structural performance and aesthetic appeal ensures its continued relevance and widespread use in modern construction.