A plane or spatial structure generally composed of straight rods, usually with triangular units. Under load, the truss members mainly bear axial tension or compression, thus fully utilizing the material's strength. In cases of large spans, it can save materials and reduce self-weight compared to solid-web beams, while increasing rigidity. Therefore, it is suitable for large-span load-bearing structures and tall structures, such as roof trusses, bridges, power transmission line towers, satellite launch towers, hydraulic gates, crane frames, etc. Common types include steel trusses, reinforced concrete trusses, prestressed concrete trusses, wooden trusses, composite steel and wood trusses, and composite steel and concrete trusses. Trusses can be classified by shape into triangular trusses, trapezoidal trusses, polygonal trusses, parallel chord trusses, and Warren trusses (empty-belly trusses). When selecting a truss type, the purpose, material, support method, and construction conditions should be comprehensively considered. On the premise of meeting usage requirements, efforts should be made to minimize the materials and labor required for manufacturing and installation.
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