Forming an HSS has to do with the processes and monitors being carried out in modern constructions and engineering works. Such engineering works are considered to be one of the strongest and are the most versatile options available in construction and civil engineering. While using these engineering works in construction, great features in regards to the aesthetics of the structure are to be taken to positively complement the architecture of the structure. Among the available engineering works, the most admired and most popular works include Round Hollow Sections and Square Hollow Sections.
The toughest and most important option in construction works of civil engineering is deciding on the shape of engineering works members. Round and Square members have their balance of aesthetics, pricing, and simplicity that is being taken into deep consideration.
What Are RHS and SHS Hollow Sections
Determining the work to be done before the in-depth computational analysis has to be taken is:
- RHS (Round Hollow Sections): These RHS are noted to be the round-shaped closed sections of the RHS. The engineering works are closed with floors and roofs that the RHS do, and the RHS also has the tendency to have closed round edges.
- SHS (Square Hollow Sections): Are steel sections with a square outer shape. Their sharp edges and flat surfaces enable easy and convenient fittings and welding. In architectural and structural engineering, designs with frequent intersections of lines and angles rely heavily on RHS.
Both VIS, ASTM A500 and EN 10210 are examples of international standards that classify constructions as predominantly RHS or SHS made from carbon steel, stainless steel or applicable alloys.
Differences between Round Hollow Sections and Square Hollow Sections
When the decision involves RHS versus SHS, a few critical elements make the difference.
1. Building Performance
- Round Hollow Sections: The shape of the RHS aids in its resistance to bend and torsional stress. Because the stress is distributed evenly along the RHS, it is well suited to columns and trusses that are placed under multidirectional loads.
- Square Hollow Sections: SHS has flat surfaces and resists bending in two primary directions. This makes it well-suited to beams, frameworks, and other applications where loads are placed along two axes.
2. Fitting and Welding
- RHS: Surfaces are worse suited to welding because of the increased difficulty that is placed on the welder due to the RHS surfaces, as well as the necessity for careful preparation and a well-trained constructor to guarantee that the RHS joints are strong.
- SHS: Flat surfaces make welding, drilling, cutting, and fabrication simpler and connections easier.
3. Aesthetics and Design
- RHS: Has a modern, clean, and simple style, which is preferred for architecture where smooth curves and distinctly minimalistic designs are used.
- SHS: Is preferred for structures with clean, simple outlines, right angles, and geometric designs which are typical for industrial and commercial structures.
4. Strength and Material Efficiency
- RHS: Usually provides a better strength to weight ratio when torsional resistance is a consideration.
- SHS: Efficiently used in structural elements subjected to bending and compression, which are aligned along principal axes, with the material being saved.
5. Weight and Material Efficiency
- RHS: Typically provides better strength-to-weight ratios when torsional resistance is a priority.
- SHS: Provides efficient material use in load-bearing applications with bending and compression forces concentrated along principal axes.
Applications where RHS is Preferred
Round hollow sections are preferred in several situations:
- Columns and Supports: RHS is used as a vertical support in buildings and bridges because it can handle axial and bending loads coming from different angles.
- Mechanical and Automotive Components: Roll cages, bike frames, and scaffolding systems are examples where RHS is torsionally resistant.
- Architectural Features: Smooth, curved RHS is beneficial for facades, canopies, and handrails by adding aesthetic value.
- Piping and Fluid Transport: Apart from structural purposes, with its unique shape, RHS is also beneficial in conduits and pipes.
Where Square Hollow Sections Excel
Square hollow sections have particular benefits in other situations:
- Frames and Trusses: The flat surfaces of RHS allows simpler and stronger connections, which is an advantage in frames and modular constructions.
- Civil and Industrial Buildings: Their pleasing and structural appearance is compatible with box-like structures.
- Fences and Gates: The flush surfaces enable straightforward production of gates, railings and fences.
- Bridges and Other Heavy Structures: The capability of carrying loads in two axes is beneficial with bridge decks and supports for heavy machines.
Factors to Consider When Choosing Between RHS and SHS
Choosing the correct hollow section is not a matter of choice of shape only. Instead, and more importantly, the choice is dictated by the requirements of the particular project:
- Types and Directions of Load: Consider whether the dominant force is torque or bending. For multi-directional stresses, RHS is more suitable. For bi-axial bending, SHS is more suitable.
- Closure of the Structural Element: If the structure is highly compartmentalized with many welded joints, the pieces will be cheaper and easier to weld if RHS is used.
- Aesthetic Choices: If the structure is more flowing and modern, RHS is more appropriate. If the structure is industrial or more box-like, SHS is more desirable.
- Fabrication Facilities and Expertise: Assess the manufacturer capabilities. Do they have any experience with working on complex curved joints or prefer simpler flat surfaces?
- Corrosion Resistance Needs: Both can be coated or galvanized, albeit the application methods may differ slightly depending on the shape.
- Cost Constraints: Assess the overall project total, which involves the purchase of the material, its fabrication, and installation.
Quality and Standards Compliance
In whichever case, RHS or SHS, the sections ought to be of accepted quality. Steel grades, wall thickness, tolerances, and surface condition ought to comply with the following:
- IS 4923 (Indian Standard for HSS)
- ASTM A500 (Standard Specification for Cold-Formed Welded and Seamless Carbon Steel Structural Tubing in Rounds and Shapes)
- EN 10210 (European Standard for Hot Finished Structural Hollow Sections)
Compliant products guarantee consistent performance and reliable mechanical properties.
Best Practices for Procurement and Use
- Source from Certified Suppliers: Always buy only from manufacturers with good reputation who issue test certificates and provide traceability.
- Specify Appropriate Grades and Sizes: The structural engineer’s recommendations should be followed for the dimensions of the cross section and the grade of steel.
- Surface Treatments: Galvanization and powder coating can extend the life of the sections in highly corrosive environments.
- Fabrication Needs: Communicate with fabricators concerning the shape of the hollow section to prevent expensive alterations later on.
- On-Site Handling: Prior to installation, care must be taken to avoid physical damage and corrosion through proper storage and handling procedures.
Summary: Making an Informed Decision.
Both section types offer unique, beneficial features that can be employed depending on the requirements of the project. RHS is advantageous when the project requires handling of torsional resistance, aesthetic smoothness, and multidirectional load. The SHS is favorable when the project requires bending resistance along the principal axes, ease of fabrication, and design angles.
After analyzing the structural loads, fabrication needs, goals around the aesthetics, and the budget, you can choose the optimal hollow section that will be safe.
Is your project looking to make the right decision on hollow structural sections?
Moglix Business is able to assist you with our widely available certified RHS and SHS products tailored to the needs of different construction and industrial projects. Get in touch to get expert recommendations on supply options.
