<script data-ad-client="ca-pub-6864624463949406" async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>Properties-Civil Engineering Reinforcement
1. TMT BARs: Thermo Mechanically Treated Bars
2. HYSD Bars: High Yield Strength Deformed Bars
3. CTD Bars: Cold Twisted Bars
4. Ultimate tensile strength (UTS)
of mild steel: 410-470 N/mm2 (IS : 432 ( Part I ) –T-1)
5. Yield stress of mild steel: 215-250 N/mm2 (Do)
6. UTS of medium tensile steel: 510-540 N/mm2 (Do)
7. UTS of high tensile steel: 1000-2200 N/mm2 ( Generally)
8. The modulus of elasticity of steel:
200000 N/mm2.(CL. 5.6.3 of IS 456)
9. Properties of steel Beam/channel, rolled section:NBCC Part-6, Section 6 and P/13 of I.S. Code.
10. Hooks shall conform to: 10d or 75 mm whichever is maximum, d=diameter of reinforcement.
11. Minm. dia of Bars in Slab: 8mm
12. Maxm. diameter of reinforcinq bar: shall not exceed 1/8th of slab Thickness
13. Minimum reinforcement of mild steel in slab: 0.15% of Gross cross sectional area of slab i.e 0.15 x B x D, B=1000mm, D=Overall depth of slab. 26.5.2.1 of IS456-2000
14. Minimum reinforcement of deformed steel in slab: 0.12% of Gross cross sectional area of slab i.e 0.15 x B x D, B=1000mm, D=Overall depth of slab. 26.5.2.1 of IS456-2000.
15. Minimum Tension reinforcement in Beam: Ast /(b*d)= 0.85/fy,
Ast.
= minimum area of tension reinforcement,
b=
Breadth of the beam,
d=
effective depth of the beam.
b= Breadth of the beam, D= overall depth of the beam: (26.5.1.1 of IS456-2000)
26. Maximum spacing of shear reinforcement: Shall not exceed 0.75 d for vertical stirrups and d for inclined stirrups at 45°where d is the effective depth of the secti on under consideration. 1n no case shall the spacing exceed 300mm.
Exposure Nominal Conc. Cover not Less Than
Mild 20mm
Moderate 30 mm
Severe 45 mm
Very severe 50 mm
Extreme 75 mm
28. Weight of Reinforcement:
One can calculate weight of reinforcement as per following:
Considering dia of reinforcement: 20mm.
Area of one bar= π*d^2/4=(3.141592*(0.020)^2)/4=3.141592*10^(-4) m2
Volume of 1 m length, V= Area x 1m.= 3.141592*10^(-4) x 1= 3.141592*10^(-4) m3
Unit wt. of steel, p=7850 kg/m3
Weight per m. length = V*p= 3.141592*10^(-4) m3 x 7850 kg/m3 = 2.47kg.
Dia in mm: Unit Wt in Kg/m
6mm 0.22
8mm 0.395
10mm 0.62
12mm 0.89
14mm 1.21
16mm 1.58
18mm 2.0
20mm 2.47
22mm 2.98
25mm 3.86
28mm 4.83
32mm 6.32
36mm 8.0
40mm 9.88
Cross sectional area of Bar
Dia in mm: C/s Area sqcm
6mm 0.283
8mm 0.50
10mm 0.785
12mm 1.131
14mm 1.53
16mm 2.01
18mm 2.54
20mm 3.14
22mm 3.80
25mm 4.91
28mm 6.158
32mm 8.04
36mm 10.18
40mm 12.566
28: Minimum Lap of Reinforcement=50D, where D is the diameter of BAR.
29. Check for maximum spacing of reinforcement in Slab as per Cl- 26.3.3 of IS 456: 2000
1. 3 x Effective depth of the slab.
2. or 300mm whichever is smaller
30. Check for Minimum spacing of bars: shall usually be not less than the
1. Diameter of the bar if all bars of equal diameter
2. Diameter of the larger bar if bars are of unequal dia and
3. 5mm more than the nominal maximum size of aggregate.
31. Spacing of Distribution Steel: As per Cl. 26.3.3 of IS 456–2000
The horizontal distance between parallel reinforcement bars provided against shrinkage and temperature shall not be more than five times the effective depth of a solid slab or 450 mm whichever is smaller.
32. Essential Check
1. All reinforcement shall be free from rust, loose scales, mud, oil, free from paint.
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