how to calculate the steel for rcc slab?
plz tell me the formula for calculating the steel?
Answer Posted / aanand babasaheb chougule
Design steps of one way slab
1. Depth of slab
d= lx/20 * M.F. (M.F. = Modification factor)
Assume the dia. of bar (8, 10, 12) and
Final overall depth
D= d+15+0/2
d= d-15-0/2
2. Effective Span
This is taken as the lesser of the followings
a) Center to center distance between followings
L= lx + t
L= lx + d
3. Load
Consider 1m width of the slab and find out the total udl
a) W = (Self weight + Live Load + Floor finish)
b) Find factor load
Wu = 1.5 * w
4. Factor bending moment
Mu = Wu * l²/8
5. Equating Mu limit to Mu find the depth req. if it is
less than‘d’ than O.K otherwise
Increase D & repeat 2, 3, and 4
Mulimit = Mu
6. Area of main steel
Pt = 50fck/fy (1-√1 – 4.6 Mu / fck bd²)
Ast = Pt/100 *100* d
7. Spacing of main steel
S = Area one bar * 1000/ Ast
Check: - a) 3d
b) 450 mm
8. Distribution Steel
Astd = 0.15 % of Ag -Fe 250 (mild)
= 0.12% of Ag – Fe 415/5000 (torque)
Ag = b.D
9. Spacing of distribution steel
S= Area one bar * 1000/ Astd
Check: - a) 5d
b) 450 mm
10. Check for depth
a) Žv = V/bd
b) Pt —› Zc
c) Zv < Zc …….. No shear reinforcement req.
| Is This Answer Correct ? | 146 Yes | 35 No |
Post New Answer View All Answers
If u want ur Ans.Of any Question so mail me skatiyar011@yahoo.in
Explain the Strength of brick?
Curing time for 1)R.C.C slab 2)B.W 3)Plastering
percentage of metal,clay or soil & water in water bond macadam roads to know the quantities for each in total volume of 11500 cubic meters
How should we design a brick column and footing?(note: no reiforcement to be provided) Can you tell me any reference book where i could possibly find this design? Plz help urgently
What is the tensile strength of marble?
What is meant by scaffolding coefficient?
What is capicity of cap lock scffolding stander(vertical member) and ledger of different size?
What is thumb rule in quantity and cost estimation of a residential building?
What is the Maximum %age of Steel in columns and beams ?
VAT and CST ? Which benefits for buyer ? Why benefits?
What are your goals?
What happens when,in Prestressed girder the HDPE duct and cone size is provided more than required? (technical answer expected)
Kindly post me previous year interview questions with answer for post of Manager (civil engg.) for NTPC, IOC , GAIL etc. I have interview on july 2013.I will be very grateful to you. Please guide me.
What is unit weight of normal concrete?