Why is Reinforcement Inserted in Concrete

Concrete is very strong in compression but weak in tension. To compensate for low tensile strength in the concrete reinforced bars are inserted. Thus the concrete is strengthened by steel, and the resultant composite mass is called Reinforced Cement Concrete.

Now the question runs in your mind. Why is concrete weak in tension?

Well, concrete is strong in tension, but the compressive nature of concrete is ten times stronger than tension.

Compression force in concrete = 10 x Tension force of Concrete

Now to be specific, concrete is made by mixing Cement, Sand, water, and aggregate. Aggregate plays an important role to carry compressive forces, and the remaining mixture (Cement, Sand, Water) acts as a glue to join these aggregates. When force is applied to a concrete member, this glue transfers compressive stresses from one aggregate to another.

In technical terminology, the glue is called as an Interfacial Transition Zone.

When concrete is under tension. The aggregates will pull away from each other. The glue which holds the whole system is significantly weaker than aggregates.

Due to the applied pull force, the glue which holds different constituents of concrete together will break.

So under tension, this zone will act as a weak link and concrete will fail at a lower force.

So, the steel bars are accommodated in concrete for tension requirements as steel has a similar value of compression and tension.

One Comment on “Why is Reinforcement Inserted in Concrete”

Leave a Reply

Your email address will not be published. Required fields are marked *