Futuristic structure made of interconnected steel beams symbolizing strength and innovation

DIY Steel Beams: Are They Stronger & Cheaper Than You Think?

Reese Marlowe in Tech & Innovation August 2025 • 4 min read.

"Exploring the Numerical Design and Strength of Cold-Formed Steel Structures."

In today's construction world, cold-formed steel (CFS) is gaining major traction. Think lighter structures, creative designs, and a boost in efficiency. But here's the catch: the thin-walled nature of CFS makes it prone to buckling, presenting a unique challenge for engineers and builders. This is where innovative designs and precise calculations become super important.

Dealing with buckling usually means beefing up designs using methods that can sometimes feel a bit outdated. The "effective width method" and the "direct strength method (DSM)" are two popular approaches, but they each have their limitations. The effective width method simplifies stress distribution, while DSM offers a more complete cross-section analysis. However, neither fully captures the complex interactions within built-up CFS members.

Now, imagine creating your own steel beams by connecting multiple CFS sections. This 'built-up' approach can increase stiffness and save money, but it also introduces more complexity. How do you ensure these DIY beams are up to par? How do you accurately predict their strength and stability? This article dives into the numerical investigation and design of these built-up CFS columns, offering insights into how to make them stronger, safer, and more reliable.

Built-Up Cold-Formed Steel Columns: Understanding the Basics

Futuristic structure made of interconnected steel beams symbolizing strength and innovation

The focus is on built-up columns made from two channel sections connected by batten plates. These plates act like stitches, ensuring the sections work together as one unit. There are two main types: open (back-to-back channels) and closed sections. While built-up sections offer advantages, their complex behavior and design challenges have limited their use. This is where new research comes in handy!

Researchers are constantly seeking ways to improve the design and analysis of CFS structures. Finite element analysis (FEA) is a powerful tool, allowing engineers to model and test designs virtually. By creating a detailed computer model, you can predict how a column will behave under different loads and identify potential weak points. This approach can lead to more efficient and reliable designs.

Local Buckling: This occurs when individual elements of the cross-section buckle.
Distortional Buckling: This involves the distortion of the entire cross-section.
Global Buckling: This is the overall buckling of the column as a whole.

A key element of this investigation involves the Direct Strength Method (DSM), a design approach that uses elastic buckling solutions for the entire cross-section. Think of it as a holistic view, rather than analyzing each element separately. This research proposes a modified DSM approach that considers the thickness of the contact area between connected sections, leading to more accurate strength predictions.

The Future of Cold-Formed Steel Design

This research paves the way for more efficient and reliable use of built-up cold-formed steel columns. By combining numerical modeling with a refined Direct Strength Method, engineers can optimize designs for strength, stability, and cost-effectiveness. As the construction industry continues to seek innovative solutions, these advancements will undoubtedly play a crucial role in shaping the future of steel construction. Whether you're an engineer, builder, or simply a DIY enthusiast, understanding the principles behind CFS design can unlock exciting possibilities for creating stronger, lighter, and more sustainable structures.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

Everything You Need To Know

What is cold-formed steel (CFS) and why is it becoming popular in construction?

Cold-formed steel (CFS) is steel that has been shaped at room temperature, resulting in thinner walls compared to hot-rolled steel. CFS is gaining traction in modern construction due to its lightweight nature, which allows for creative designs and increased efficiency. This lighter construction can lead to lower material costs and easier handling on site, making it an attractive option for builders and engineers. However, the thin-walled nature of CFS introduces challenges related to buckling, requiring careful design considerations.

What are the main methods used to address buckling in cold-formed steel, and what are their limitations?

The two primary methods for addressing buckling in cold-formed steel are the "effective width method" and the "direct strength method (DSM)". The "effective width method" simplifies stress distribution, which can be useful for initial estimations. The "direct strength method (DSM)" offers a more comprehensive analysis of the cross-section. The limitations of both methods lie in their inability to fully capture the complex interactions within built-up CFS members, especially when dealing with columns made from multiple CFS sections.

How do built-up cold-formed steel columns work, and what are the advantages and challenges associated with their use?

Built-up cold-formed steel columns are created by connecting multiple CFS sections, typically channel sections, using components such as batten plates. The batten plates act as connectors, ensuring the individual sections work together as a single structural unit. The main advantages of built-up columns include increased stiffness and potential cost savings compared to using a single, heavier section. However, their complex behavior and design introduce challenges, including the need for precise calculations to predict their strength and stability due to the interactions between the sections.

How does finite element analysis (FEA) contribute to the design of cold-formed steel structures, and what types of buckling are considered?

Finite element analysis (FEA) is a powerful numerical modeling tool used to simulate the behavior of cold-formed steel structures. FEA allows engineers to create detailed computer models to predict how a column will react under various loads and identify potential weak points. This method can lead to more efficient and reliable designs. The investigation of buckling in cold-formed steel considers several modes: local buckling, which affects individual elements of the cross-section; distortional buckling, involving distortion of the entire cross-section; and global buckling, which is the overall buckling of the column.

What is the Direct Strength Method (DSM), and how is it being improved for built-up cold-formed steel column design?

The Direct Strength Method (DSM) is a design approach that utilizes elastic buckling solutions for the entire cross-section. This is like viewing the whole structure, instead of analyzing each part separately. The research proposes a modified DSM approach that takes into account the thickness of the contact area between connected sections. This refinement enhances the accuracy of strength predictions, allowing engineers to better optimize the designs for the built-up cold-formed steel columns, contributing to more efficient and reliable structures.