A hollow structural section (HSS) or structural hollow sections (SHS) both are same. This is a type of metal profile with a hollow tubular cross section.
With high torsional rigidity and compressive strength, these hollow sections are comparably more efficient than conventional steel sections.
The excellent distribution of material around the axis of the square and rectangular steel hollow sections allows for remarkable strength qualities and thus offers decisive advantages in its applications.
Hollow steel sections (HSS) are commonly used in welded steel frames where members experience loading in multiple directions. HSS have very efficient shapes for this multiple-axis loading as they have uniform geometric and thus uniform strength characteristics along two or more cross-sectional axes; this makes them good choices for columns.
They have increased tensile capacity because of concentric connections and increased compressive strength because of higher radius of gyration. They possess full strength under bending moment due to superior torsional rigidity. Outer smooth profile ensures no trappings of dirt and water, thus reducing chances of corrosion reaction.
The HSS has superior resistance to lateral torsional buckling. They also have excellent resistance to torsion.
A higher strength to weight ratio credits these sections with nearly 20% reduction in the use of steel. HSS is commonly available in mild steel.
These sections allow for a wide range of applications as industrial sheds and exhibition stalls to space frames and sign supporting structures. The sections can also be utilised for large span portal frames, amusement parks and playground equipments, guard rails for staircases, sports galleries, pedestrian walkovers, bridges and bus stands amongst other uses.
Most American manufacturers adhere to the ASTM A500 standard, while Canadian manufacturers follow both ASTM A500 and CSA G40.21. European hollow sections are generally in accordance with the EN 10210 standard and Indian HSS are generally in accordance with the IS:4923For other steel section please refer my earlier post steel-sections. Unit Weight & Properties of Hollow sections will discuss on my next post