The production of HSS hollow steel sections in advanced ways has created many advantages for structural engineers and has increased the popularity of using these sections in recent years. Comparisons between structures in which HSS sections are used as columns or braces compared to other methods, including concrete structures and steel structures in the traditional way, show that the use of HSS sections produced in a modern way has advantages such as economic and time savings. Also, the modern production method in accordance with the international standards of these sections increases the quality and durability of steel structures.

The uses of HSS steel sections in steel frame structures

Most buildings are framed by concrete frame methods, traditional metal frame consisting of welded sheets, metal frame with HSS sections as hollow columns or filled with concrete (CFT).

The differences between production of building sections in traditional and modern ways

The production of HSS steel sections is done by traditional or modern methods. In the traditional method, it is produced by cutting and welding steel sheets together. Human error, longer manufacturing time, lower strength in welding points and also increasing manufacturing costs have encouraged craftsmen to produce these sections in modern ways. One of the modern methods of producing HSS sections is cold rolling production with direct welding, which is often done with advanced machines. In this method, the sheets stored in the line are slowly bent with multiple rollers until the two ends of the sheet are close to each other, and then they are welded together with ERW electric resistance welding, and then they are cut into desired lengths.

Advantages of using modern HSS steel sections compared to other construction steel sections

In cold rolling production, the rolling (bending) operation is done in several stages with different rollers and slowly, so that the least stress is created in the steel structure, which causes more resistance in twisting, bending and stretching. Also, ERW electrical resistance welding is integrated, with the least error and without the use of secondary material (electrode), which minimizes the stress at the welding point.

One of the most important applications of HSS steel sections is in the construction industry. The use of steel structure has advantages over other structures and building materials such as concrete that have been mentioned. Having two or more axes of symmetry and a large radius of gyration, these sections are the most suitable option as columns or beams in structural systems whose main task is to bear gravity and lateral loads.

Since the steel materials in HSS profiles have the greatest distance from the axes passing through the center of the surface compared to other steel profiles produced in the traditional way, the hollow shape of HSS is inherently more resistant and efficient. In addition, according to AISC and Iranian standards, all parts of HSS sections have both supporting edges, which delay their local buckling. Therefore, HSS has a higher strength-to-weight ratio even compared to other structural steel sections. It is obvious that less weight makes construction easier and has the ability to withstand more forces caused by earthquakes. Also, reducing the cost of installing the structure and transporting the materials leads to a better design of other parts of the building such as the foundation. This advantage makes HSS a suitable option for increasing the floors of existing buildings without imposing excessive load on the foundation.

Research shows that due to undeniable human errors in compliance with standards, in many cases the most damage to buildings after an earthquake occurs in concrete structures. It is also impossible to ignore the effect of workshop errors in the construction of steel structures in the traditional way, because in this kind of construction method due to numerous cuts and welding, it leaves a lot of residual stress, which makes the structure very vulnerable during an earthquake.

Therefore, due to the fact that many areas in the world, including Iran, are exposed to the dangers of earthquakes, there is no doubt that more care should be taken in choosing reliable and resistant materials in these areas. HSS produced by modern industrial method is considered the most suitable and reliable building structure against this natural disaster.