Steel square hollow section (SHS) and steel circular hollow section (CHS) are both commonly used structural steel shapes. The main difference between them is their cross-sectional shape. SHS has a square or rectangular cross-section, while CHS has a circular cross-section.
The strength of a steel hollow section depends on several factors such as the grade of steel, the geometry of the section, and the loading conditions. Generally, the circular shape of CHS makes it more resistant to bending and torsional forces, making it slightly stronger than SHS. However, the difference in strength between the two is usually small and can vary depending on the specific dimensions and properties of the sections.
One advantage of SHS is its flat surfaces, which make it easier to connect to other structural elements. It also has more uniform strength in both directions, making it suitable for applications where the load can come from any direction. Additionally, SHS is more efficient in terms of material usage, as it can be produced with less steel compared to CHS for the same strength.
CHS is often preferred in applications where a strong and lightweight structure is required, such as in the construction of bridges, towers, and offshore structures. Its circular shape also makes it more resistant to buckling under compressive forces, making it suitable for columns and other vertical members.
In most cases, SHS and CHS can be used interchangeably depending on the structural requirements and design considerations. However, it is important to consult with a structural engineer to ensure that the selected section is suitable for the specific application and can withstand the expected loads and stresses.