The Unbreakable Bond Between Concrete and Steel

by Tendon, on Jul 31, 2023 8:52:03 AM

Skyscrapers. Bridges. Parking decks. Arenas. They are a part of daily life, but do you ever think about what gives these structures strength and durability? It’s concrete and steel.  Combined, these two strong materials create infrastructures that stand the test of time.

Concrete is Strong Under Pressure

Made by mixing cement, water, and aggregate (like sand or gravel), concrete has been a game-changer in the construction industry since the Romans invented it more than 2000 years ago. Alone, it is known for its incredible compressive strength, meaning it can withstand a great deal of pressure or weight pushing down on it. This makes it a perfect material for constructing buildings, roads, and bridges.

However, concrete does have its limitations. While it is mighty under compression, it fares poorly under tension - it cannot handle being stretched or pulled very well. That's where steel reinforcement comes in.

Steel Can Handle the Tension Concrete Can’t

Steel, unlike concrete, stays strong under tension and compression. It's flexible and able to withstand stretching forces without breaking. When steel reinforcing bars, or 'rebar,' are embedded within concrete, they compensate for its weak tensile strength. The result is a composite material known as reinforced concrete.

But why steel? Why not any other metal or material? There are four key reasons concrete and steel work well together:

  1. Similar Thermal Expansion: Concrete and steel have similar coefficients of thermal expansion. This means they expand and contract similarly under fluctuating temperatures, preventing internal stresses that could lead to cracking.
  2. Adherence: Concrete adheres well to steel, facilitating a solid bond between the materials. This allows them to act together when load forces come into play, making the overall structure significantly more resilient.
  3.  Availability and Cost: Steel is widely available and relatively affordable, making it a practical choice for reinforcement.
  4. Recyclability:  Steel is 100% recyclable, making it a sustainable choice in the face of growing environmental concerns. Annually, CMC recycles more than 19 billion pounds of metal. To learn more about metal recycling, visit us at

How Does Steel Reinforce Concrete?

Creating reinforced concrete involves forming a grid-like structure with steel rebar, then pouring the concrete mix around it. As the concrete hardens, it firmly grips the steel, capitalizing on the strengths of both materials.

The steel rebar absorbs the stresses in a structural framework, enhancing the overall sturdiness and reducing the risk of cracking or failing under load.

The Impact of Reinforced Concrete is Felt Far and Wide

Reinforced concrete has revolutionized the world of architecture and civil engineering. We can construct longer bridges, taller skyscrapers, and more complex structures that will be safe for many years.

Not only does reinforced concrete offer superior strength, but it also provides resistance to weather conditions, fire, and even earthquakes when designed correctly. It is the material of choice for most infrastructure projects worldwide.

So, the next time you pass by a construction site, take a moment to appreciate the strength of reinforced concrete. If you need expert insight on reinforced concrete construction, please contact us today. 

Your Expert Concrete Construction Company

For over 30 years, Tendon Systems now a part of CMC has been an industry-leading provider of post-tensioning, barrier cable, and restoration services across the United States. Built on a foundation of quality products, exceptional services, and engineering expertise, the Tendon team has what your project needs to succeed on time and within budget.