Concrete is a versatile and durable building material and provides an excellent foundation for most types of buildings. Although it offers many strengths, it does have its limitations.  Concrete is strong in compression but weak in tension.  To overcome this limitation, concrete can be reinforced with steel which offers additional strength and flexibility improving its versatility and durability.  Here we will outline when to reinforce concrete and why it may be required to do so.  

Why Reinforce Concrete?

The most obvious benefit of reinforcing concrete is to improve its tensile strength.  

Steel reinforcement offers concrete flexibility, allowing it to stretch without breaking and enables it to withstand forces and conditions that would usually cause it to fail.  

Reinforced concrete can bear many heavy loads and is therefore suitable for structures likely to be subject to high stress such as concrete bases.  Reinforcement also enhances durability, expanding the lifespan of concrete and making it much more resilient to weathering and chemical reactions.  

Concrete that has been reinforced allows flexibility and more ambitious architectural designs that probably would not be possible with standard, plain concrete.  It also enables the thickness of structural elements to be reduced which in turn keeps costs down.  

Types Of Concrete Reinforcement

Concrete is often reinforced with steel.  Concrete alone is useful in a limited number of applications because it is strong against compression forces, but it is weak when it comes to tension and shear forces.  Steel is a material that helps to overcome these weaknesses and offers many excellent properties:  

  • Steel is highly ductile, it can be manipulated or bent into shape and will not break, it will simply stay bent.  
  • Steel and concrete have similar coefficients of thermal expansion.  When they are subjected to high or low temperatures they will expand or shrink at roughly the same rate.
  • Steel forms a strong bond with concrete and undergoes the same strain as concrete.
  • Steel is also easy to weld, recyclable and is both widely available and affordable.

There are a few choices of concrete reinforcement to consider:

  • Steel Bars - This is the most widely used type of reinforcement, and it's found in everything from motorway bridges to building foundations.

  • Mesh - Wire mesh is often used to reinforce flat structures and concrete slabs where the primary concern is the risk of cracking triggered by temperature changes and settling.  Mesh can be tricky to handle, work with and transport.

  • Fibre - Fibres such as glass, steel or synthetic compounds can be added to a concrete mix to provide reinforcement.  This is a popular choice for applications such as concrete bases and driveways and offers outstanding strength for domestic and light commercial uses.  

When To Reinforce Concrete

Structural elements that are subject to high stress such as beams, columns and slabs will require reinforcement to ensure they can handle the imposing loads.  It’s unlikely that reinforcement will have any negative impact in such applications, therefore it seems wise to introduce reinforcement of some kind.   It is advisable to reinforce concrete bases in almost all cases and fibre is the chosen option for most ground workers because it can be introduced at the mixing stage and doesn’t affect the way the concrete is poured or laid.    

Other Considerations

Can Existing Concrete Be Reinforced?

Technically, yes it is possible but it is a complex procedure that will require complex structural assessments and a specialised equipment and techniques.  Generally, reinforcement should be added at the stage of concrete pouring.  

Is Reinforced Concrete Maintenance Free? 

Not entirely.  It is certainly more durable but should still be regularly inspected for signs of damage and wear and tear.  You’ll need to be aware of corrosion in some environments.

To Conclude

Reinforced concrete offers many positive benefits for construction projects of all kinds, including greater load bearing abilities, enhanced tensile strength and improved durability.  Understanding concrete reinforcement can make a significant difference to the longevity of and success of any project, so whatever your next concrete project involves, consider the benefits of reinforcement.