How To Select The Best TMT Bars for Building A House

TMT bars are an important component in the construction of any building including houses. When used with concrete, they give structural integrity to the construction. They also help in safeguarding buildings against damage from seismic activity by enabling the elongation of the members of the construction under tension. Therefore, in constructing a house, it is important to choose top-quality TMT bars or rebars for ensuring the highest level of strength and safety.

The quality of TMT bars is directly dependent on the quality of the manufacturing processes. Manufacturing of TMT bars needs to be done in a tightly controlled environment to ensure that the products conform to standards and are free from impurities. Therefore, before buying TMT bars, it is important to research the company that is producing them to ensure that they are complying with the highest standards of production. Here are a few pointers to keep in mind while selecting the right brand for TMT bars -

BIS Standard IS-1786

Bureau of Indian Standards (BIS) has published a product manual for high strength deformed steel bars and wires for concrete reinforcement. Reputed companies ensure that they follow this product manual to the tee in producing TMT bars.

TMT bar grades

TMT bars are of various grades - Fe-415, Fe-500, Fe-550, and Fe-600. The “Fe” in the name stands for iron and the figure represents the minimum yield stress in MPa. The most commonly used TMT bar in construction of houses is the Fe-500 grade TMT bar which has optimal levels of strength and ductility.

Free from harmful gases

In the steel production process, if the level of carbon is lower than optimum, the excess oxygen in the cast reacts with carbon to form carbon monoxide. Additionally, it may create other oxides that are harmful to the steel. Top quality steel is produced when it is deoxidized using agents like aluminium or silicon. While buying TMT bars, ensure that they are free from dissolved gases such as oxygen, hydrogen and nitrogen and other harmful impurities like oxides.

Corrosion Resistance

Due to the presence of iron in steel, even TMT bars are not rust-proof. However, they can be made corrosion-resistant by carrying out the process of Quenching properly. In Quenching, a hot bar is rapidly cooled with water jets of varying temperatures. This process causes the creation of a hard, highly tensile outer layer on the bar called “martensite” which also makes the TMT bar corrosion-resistant.

Optimal Rib Area

Ribs on TMT bars help in bonding the bars with concrete and evenly distributing load on the bars, thereby giving strength to construction. BIS specifies rib area on the bars. Before buying TMT bars, one must check if the rib area complies with the BIS standards.

Super Ductility with 18% elongation

The minimum level of elongation specified for TMT bars is 12%, but the higher the elongation, the more ductile and capable of withstanding tension they are. 18% elongation is optimal for TMT bars.

Use of LRF

Ladle Refining Furnace (LRF) is used for refining molten metal. Top quality steel undergoes desulphurizing processes in LRF which removes its impurities and perfects its chemical composition.