Concrete reinforced with TMT iron rods has become a very popular structural material used by construction experts in civil engineering structures for several decades. The popularity and wide acceptance of reinforced concrete is as a result of its strength. But despite its use, reinforced concrete needs an improvement in terms of bond strength as well as the interface between TMT iron rods and concrete.
Reinforced concrete is the combination of concrete, which is relatively strong and durable in compression, and TMT iron rods which are strong and ductile in tension. Though the two materials are different, they must act together in reinforced concrete structure. This is to give the structure ability to bear the huge load it is designed to bear, and resist natural disasters like earthquakes. But this can only happen when the concrete holds the TMT iron rods firmly to form stronger bond. Bonding here means the concrete holds the TMT iron rods firmly.
Importance of Bonding Between TMT Iron Rods and Concrete
The bond strength between TMT iron rods and concrete is as important as the compressive strength of concrete in a reinforced concrete structure. Bonding between the two materials is important both in terms of structural behaviour as in relation to cracking caused by shrinkage and thermal effects at early ages.
Maintaining composite action between concrete and TMT iron rods requires transfer of loads and stresses and bond between the concrete and steel layers. This load transfer is referred to as bond strength mechanism.
Factors Determining Bond Strength in TMT Iron Rods
Bond is a shearing stress between the surface of reinforced concrete and the surrounding concrete. The factors that determine bond strength include chemical adhesion, friction and uniform rib structure of TMT iron rods. Friction is a mechanical interlock between irregularities of steel surface and concrete, with magnitude superior than adhesion and occurs after the adhesion is broken and some small movement between steel and concrete take place.
The uniform rib structure of TMT iron rods makes them form a stronger bond with concrete, thus providing additional support and unmatchable strength to the whole structure. Any iron rods with deformed or non-uniform rib structure will have weaker bonding throughout the structure.
Effects of Bond Strength on Structures
Bond strength is a very important and well sort after-quality of concrete for reinforced concrete structural elements.
A perfect bond, existing between concrete and TMT iron rods, is one of the fundamental assumptions of reinforced concrete. The bond strength of concrete is a function of compressive strength and is approximately proportional to the compressive strength.
The good surface and critically-designed ribs of TMT iron rods, enabled by their good chemical properties, make them enable bond well with concrete and cement. This also gives them good fatigue strength.
By bonding perfectly with concrete and cement, TMT iron rods improve the durability, longevity, and lifespan of buildings and structures by making them free of defects such as seepage, cracks and moisture which can cause structural damage.
From the foregoing, one can see that it is essential to use a TMT brand that possesses perfect bonding with concrete for any construction project. This will ensure that your structure is defect-free, safe, durable and last longer.