What is Steel Truss and what are its main uses in building structures?

Steel Truss is a rigid structural system composed of steel components through triangular units. Its core feature is to use axial force to transfer loads instead of the bending stress of traditional beam structures. This design makes steel trusses have both high strength and light weight advantages, making them the preferred solution for large span and high load scenarios. In industrial plants, stadiums, bridges and high-rise buildings, steel trusses are driving modern engineering towards a more efficient and sustainable direction with their unique performance.
Steel trusses use triangles as basic units and realize load transfer through axial forces of the upper chord, lower chord and web. Compared with solid web beams, the strength advantage of steel is maximized, and the material consumption can be reduced by 30%-50% under the same span. For example, if an industrial plant with a span of 18 meters uses a steel truss roof, its self-weight is only 1/4 of that of a concrete structure, but it can carry the same or even higher dynamic loads. This characteristic makes it particularly outstanding in extreme conditions such as earthquake resistance and wind resistance, such as the lattice steel trusses widely used in transmission towers and satellite launch towers.
1. Large-span spatial structure
Steel trusses are good at spanning very large spaces without intermediate supports. Large exhibition centers and airport terminals often use parallel chord or curved steel trusses, with a single span of more than 150 meters. The roof of Shanghai Hongqiao Transportation Hub uses a two-way steel truss grid to achieve a column-free space, taking into account functionality and visual transparency.
2. Strengthened support for high-rise buildings
In super-high-rise buildings, steel trusses are used for transfer layers or reinforcement layers. For example, Shenzhen Ping An Financial Center uses giant steel trusses to connect the core tube to the outer structure, significantly improving lateral stiffness and resisting strong winds and earthquakes.
3. Industry and infrastructure
In industrial plants, steel trusses can integrate pipeline channels and equipment hanging functions to reduce floor height occupancy. In the field of bridges, cantilever steel truss bridges (such as the Nanjing Yangtze River Bridge) are prefabricated in sections and assembled on site to achieve rapid construction under complex hydrological conditions.
4. Detachable temporary structures
In temporary facilities such as exhibitions and stages, modular steel trusses can greatly reduce construction costs by virtue of their rapid assembly and reuse characteristics. Aluminum alloy trusses have become an ideal carrier for lighting and sound equipment through lightweight design, and can support weights up to 3 times that of traditional structures.
Technological evolution and value upgrade
Modern steel trusses have broken through the limitations of a single function and developed towards composite and intelligent development. For example, the combination of special-shaped steel trusses and hyperbolic tube structures can not only shape the appearance of a streamlined building, but also optimize mechanical properties. The application of digital design tools (such as BIM) enables node accuracy to be controlled at the millimeter level, and construction efficiency is increased by more than 40%.