Building home requires several factors to be taken under consideration to get the best result. Before you start the construction of your home you need to have the perfect planning, accurate estimation and best quality building materials. In construction Rebar is one of the prime materials that makes your home • Fire Resistant • Earthquake Resistant Thus, it is important to choose the best quality Rebar that has the perfect balance of strength & flexibility and makes your home everlasting. TMT Bars are widely used for its ductility and bendability. TMT Bar is an advance technology that used in all type of construction. The Thermo Mechanical Treatment results strong outer martensite layer in outer side that results the tensile strength to it and soft ferrite-pearlite inner core makes it highly ductile. TMT Bars are well known for its bendability.

1. Study Of Steel Reinforcement Bars
Presented by
P. Ashok Kumar (20GG1M1431)
V. Aastritha Vatchala (20GG1M1448)

2. Introduction
• Steel reinforcement is a versatile
constructional material which is widely
used in the construction industry for
making of the reinforced concrete.
• Reinforcement concrete (RC) is a
composite material made up of concrete
and some form of reinforcement – most
commonly steel rods, bars, wires or mesh
of steel rods and steel wire
• Steel reinforcement used as a tension
device in reinforced concrete and
reinforced masonry structures to strengthen
and aid the concrete under tension.

3. Types of rebars
Mild steel and medium tensile bars conforming to IS 432 (Part I)
High strength deformed steel bars conforming to IS 1786
Hard drawn steel wire fabric conforming to IS 1566
Structural steel conforming to Grade A of IS 2062
Thermo-mechanically treated (TMT) Bars.

4. Mild steel & medium tensile bars
Mild steel bars are used for tensile stress of RCC slab beams etc. in reinforced cement concrete
work. These steel bars are plain in surface and are round sections of diameter from 6 to 50 mm.
These rods are manufactured in long lengths and can be cut quickly and be bent easily without
damage.
Various Grades of Mild Steel Bars
1) Mild steel bars can be supplied in two grades
a)Mild steel bars grade-I or Grade 60
b) Mild steel bars grade-II or Grade 40
2) Medium Tensile Steel Bars or Grade 75

5. Physical Requirement of Mild Steel Bars
Types of Nominal size of bar
Ultimate Tensile Stress in
N/mm2
Yield Stress N/mm2 Elongation Percentage min
Mild Steel Grade I or Grade 60
For Bars upto 20mm 410 250 23
For Bars above 20mm upto
50mm
410 240 23
Mild Steel Grade II or Grade 40
For Bars upto 20mm 370 225 23
For Bars above 20mm upto
50mm
370 215 23
Medium Tensile Steel Grade -
75
For Bars upto 16mm 540 350 20
For Bars above 16mm upto
32mm
540 340 20
For Bars above 32mm upto
50mm
510 330 20

6. TMT bars
 Thermo Mechanically Treated Bars are hot treated
bars that are high in strength used in reinforced
cement concrete (RCC) work.
 It is the latest induction in the MS steel bars with
superior properties such as strength, ductility,
welding ability, bending ability and highest quality
standards at international level.
 TMT Bar manufactured in different grades. The
grade denotes yield strength of TMT Bar. The
grade starts from Fe 415 and goes up to Fe 600.
As per IS Standards Fe500d grade TMT Bar has the
perfect combination of Strength & Flexibility.

7. • Mild steel (MS) rebars were introduced initially as a reinforcing
material (Fe215 – Fe250)
• Cold twisted deformed (CTD) rebars were introduced replacing MS
rebars
• Yield strength of CTD bar Fe 415 against Fe250 of MS bars i.e. approx.
60% higher strength than MS bars
• Later on Thermo mechanically treated (TMT) bars were introduced
with approx. 60% higher strength than CTD bars

8. There is no BIS code for TMT bars. The available code BIS 1786 pertains to HSD Bars.
The TMT bars are being produced under valid licence from either of the firms namely
Tempcore, Thermex Evcon Turbo & Turbo Quench.
The TMT bars shall conform to IS 1786 pertaining to Fe 415 D or Fe 500 D or Fe grade
of steelas specified.
In design and construction of RC buildings in seismic zone III and above, steel
reinforcement of Grade Fe 415 D shall be used.
The TMT bars produced of grade Fe 415, Fe 500 and Fe 550 having elongation more than
14.5. % and conform to other requirements of Fe 415 D, Fe 500 D and Fe 550 D
respectively of IS 1786 may also be used for reinforcement.

9. Mechanical
properties
(IS:1786)
Grade Fe-415 Grade Fe-500 Grade Fe-550 Grade Fe-600
Yield strength
(Min Mpa)
415 500 550 600
Tensile strength
(Min Mpa)
485 545 585 660
Elongation (%) 14.5 12 10 10
Chemical properties
(IS:1786)
Grade Fe-415 Grade Fe-500 Grade Fe-550 Grade Fe-600
Carbon (max) 0.30 0.30 0.30 0.30
Sulphur (max) 0.060 0.055 0.055 0.040
Phosphorous (max) 0.060 0.055 0.050 0.040
S + P (max) 0.110 0.105 0.100 0.075

10. Mechanical
properties
(IS:1786)
Grade Fe-415 D Grade Fe-500 D Grade Fe-550 D
Yield strength
(Min Mpa)
415 500 550
Tensile strength 500 565 600
Elongation (%) 18 16 14.5
Chemical properties
(IS:1786)
Grade Fe-415 D Grade Fe-500 D Grade Fe-550 D
Carbon (max) 0.25 0.25 0.25
Sulphur (max) 0.045 0.040 0.040
Phosphorous (max) 0.045 0.040 0.040
S + P (max) 0.085 0.075 0.075

11. Manufacturing process of TMT bars

13. • The primary-secondary ratio is approximately 45:55.
• There are a few primary quality manufacturers, such as
SAIL, TATA Steel , RINL ,JSW Steel, JSPL and Essar Steel.
• Meanwhile, about 500 secondary quality manufacturers are
spread across India

14. manufacturers
1. Tata Steel Ltd
2. JSW Steel Ltd
3. Steel Authority of India Ltd
4. Jindal Steel & Power Ltd
5. Rashtriya Ispat Nigam Ltd. (RINL)
6. Electro steel Steel Ltd.
7. Shyam steel
1. Tata Steel Ltd
2. JSW Steel Ltd
3. Steel Authority of India Ltd (SAIL)
4. Jindal Steel & Power Ltd (JSPL)
5. Rashtriya Ispat Nigam Ltd. (RINL)
6. MS life
7. Essar steel
Primary steel producers

15. Secondary steel producers
1.Simhadri
2.Mangal TMT
3.Black Gold
4.Narayani Ispat
5.Radha TMT
6.Shree TMT
7.Suguna TMT
8.DIIL
9.Jairaj ispat
10.Tirupati

19. Provisions of Ductile detailing as
per IS : 13920 -2016

21. Ductility

22. Beams in RC buildings
(a) long straight bars
(b)closed loops bars (called stirrups)

24. Failures in Beams :
(a) Flexural (or Bending) Failure
(b) Shear Failure

25. Spacing of Stirrups :

27. Lapping of longitudinal bars of Beams :

28. Columns in RC buildings
Columns can sustain two types of
damages
• axial-flexural
• shear failure.

29. Vertical Bars tied together with Closed Ties

32. Lapping of Vertical Bars

33. Beam-Column Joints
• .

34. Reinforcing the Beam-Column Joint

35. Anchorage Beam Bars

36. Minimum dimensions of beam and column
IS 13920 : 1993 (Cl.7.1.2)
• The minimum dimension of the member shall not be less than 200 mm.
• The shortest dimension of the column shall not be less than 300 mm
• In frames which have beams with centre to centre span exceeding 5 m or columns
of unsupported length exceeding 4 m

37. Minimum & maximum % of reinforcement at any section
of beam
As per IS 456:2000 clause 26.5.1.1,
Minimum % of reinforcement should be
As = 0.85 bd/ fy
As per IS 456:2000 clause 26.5.1.2,
Maximum % of reinforcement should be 4 % of the cross sectional area of the beam
As = 0.04bD

38. IS 13920 : 1993 (Cl.6.2.1) minimum reinforcement:
a) The top as well as bottom reinforcement shall consist of at least two bars
throughout the member length.
b) The tension steel ratio on any face, at any section, shall not be less than
Pmin = 0.24 sqrt( fck / fy)
IS 13920 : 1993 (Cl.6.2.2) maximum reinforcement:
The maximum steel ratio on any face at any section, shall not exceed Pmax = 0.025