Benefits
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The use of high strength TMT results in 10-20% saving in steel consumption.
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In developed countries, rebars with minimum yield strength of 500 N/mm2 (as against 415 N/mm2 in CTD bars) with high elongation values are specified for RCC work.
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Buland TMT rebars meet the requirement of even developed countries.
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Buland TMT rebars are stronger, more bendable and have higher thermal stability because of unique technology used.
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Buland TMT rebars ensure greater safety due to high elongation of 16-25%.
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Buland TMT rebars are the ideal choice even for Seismiczones 3, 4&5.
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Globalisation has brought in awareness in India about the deficiencies of CTD bars (and superiorities of TMT bars) as the demand for proper Quenched & Self Tempered TMT rebars is increasing even in India.
Properties
Corrosion Resistance Properties : Controlled water-cooling prevents the formation of coarse carbides which has been cited as the main cause for the corrosive nature of common bars. Another reason for better corrosion resistance properties is the absence of surface torsional stresses caused by the cold twisting (Torsteel) process.
Weldability : Buland rebars with carbon content less than 0.25% can be used for butt and other weld joints without reduction in strength at the welded joint.
Bend Properties : Buland rebars have excellent bend properties due to the unique ductility(elongation values) obtained.
Fire Resistance : Unlike Torsteel and CTD rebars, TMT bars have high thermal stability. They are the preferred choice when elevated temperature of 400-600 C may be encountered.
Earthquake Resistance : Buland TMT rebars with typical elongation of 16-25%, (well above the minimum 14.5% specified in IS 1786), are suitable for use even in earthquake zones 3,4&5.
Cost Effective : Use of Buland rebars results in savings of 10-20% compared to CTD bars for same work.
Strain Ageing : Due to unique manufacturing process and chemical composition, Buland TMT rebars show no tendency of embrittlement either during welding or cold deformation of welded joints.
Formability : Due to very high elongation values and consistent properties throughout the length of bar, Buland TMT rebars have excellent workability and bendability.
TMT BAR SPECIFICATION
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IS:1786-1985 Specified |
Buland TMT |
Carbon % |
0.30 Max. |
0.17 to 0.25 |
Manganese % |
Not Specified |
0.50 to 1.0 |
Sulphur & Phosphorus |
0.11Max. |
0.105 Max. |
Carbon Equivalent % |
0.42 Max. |
0.25 to 0.40 |
Property |
IS:1786-1985(Fe415)Gr. |
Buland TMT BarValues |
Fe 500 Grade |
BulandTMT Values |
0.2% Proof Stress / Yield Stress (Mpa)
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Deformation and Surface Characteristics ( Mean Project Area)
Size of TMT Bar |
IS: 1786 Specified |
Buland TMT Bars |
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Ar Value (Min.) |
Ar Value (50 % More) |
| 8 mm |
0.96 mm2 /mm |
Above 1.4 mm2/mm |
| 10 mm |
1.2 mm2 /mm |
Above 1.8 mm2/mm |
| 12 mm |
1.8 mm2 /mm |
Above 2.7 mm2/mm |
| 16 mm |
2.4 mm2 /mm |
Above 3.6 mm2/mm |
| 20 mm |
3.4 mm2 /mm |
Above 5.1 mm2/mm |
| 25 mm |
4.25 mm2 /mm |
Above 6.3 mm2/mm |
| 28 mm |
4.76 mm2 /mm |
Above 7.1 mm2/mm |
| 32 mm |
5.44 mm2 /mm |
Above 8.1 mm2/mm |
Parameters |
Buland TMT Bar |
CTD Bar |
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Fe 415 Grade |
Fe 415 Grade |
| 0.2% Proof Stress/Yield Stress (Mpa) |
440 Min. |
415 Min. |
| Tensile Strength (Mpa) |
525 Min. |
485 Min. |
| Elongation % |
17-25 |
14.50 Min. |
| Corrosion |
Resistant |
High Corrosion |
| Weldability |
Excellent |
Poor |
| Use at high Temperature |
Safer |
Not Recommended |
| Use in Earthquake Prone Areas |
Preferred |
Not Recommended |
| Consistency |
High |
High Variance in properties |
| Bend Properties |
Superior |
Inferior |
| Saving in steel used |
10-15% |
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| Global Use |
Preferred Choice |
Not Permitted |
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