Using high-strength steel in chords is crucial for achieving weight and cost savings. Mild S355 steel can be used for brace members, because the brace members hold most of the fabrication effort, it is usually more economic to machine and weld milder steels due to often higher tooling and welding costs for SHS. This is why a hybrid truss design, especially for long-span trusses, proves to be the most cost-efficient solution.
SSAB’s Domex double-grade hollow sections, with two test certificates for S355J2H and S420MH, thus make an ideal choice in truss design. And even where high-strength steel can be challenging in longer, slender columns due to buckling behavior, our double-grade hollow sections have been tested for compressive strength and have been granted buckling curve B. The higher strength of the tube benefits shorter columns and the improved buckling curve benefits longer columns. This combination creates a highly resistant, cost-efficient column.
Why structural hollow sections from SSAB
SSAB’s high-strength SHS steel tubes offer structural design engineers several advantages that can help solve engineering problems from the everyday to the exceptional.
Potential benefits and opportunities:
- Increase allowable design stresses by leveraging the high-yield and tensile strength. This way, you can likely reduce the wall thickness and use less steel.
- Reduce dead load and self-weight. Less substructure is needed to support a lighter superstructure, so you can gain additional savings in foundations and piling, for example.
- You can use simplified structural components and construction techniques, especially for bigger structures or heavily loaded sections. This means you can save not only on materials, but on fabrication, handling, transportation and construction.
- With thinner gauges, you can substantially reduce the volumes of deposited weld material and thus pollutants, weld consumables and weld times.
- More efficient structures let you minimize embodied carbon in structures, a growing environmental concern.