Search

Things Site Engineers Must Know About Reinforcement and Steel Bars

Posted in Student Corner | Email This Post Email This Post |
Print Friendly, PDF & Email

As Per Indian Guidelines Only.

Clear cover to main reinforcement in
Footings : 50 mm
Raft foundation Top : 50 mm
Raft foundation Bottom/ sides : 75 mm
Strap Beam : 50 mm
Grade Slab : 20 mm
Column : 40 mm (d>12mm) 25 mm (d= 12mm)
Shear Wall : 25 mm
Beams : 25 mm
Slabs : 15 mm or not less than diameter of the bar.
Flat Slab : 20 mm
Staircase : 15 mm
Retaining Wall on Earth : 20/ 25 mm
Water retaining structures : 20 / 30 mm
Sunshade (Chajja) : 25 mm

Hook for stirrups is 9D for one side

No. of stirrups = (clear span/Spanning) + 1

For Cantilever anchorage length for main steel is 69D

Advertisements

ā€œLā€ for column main rod in footing is minimum of 300mm

Chairs of minimum 12 mm diameter bars should be used.

Minimum diameter of dowel bars should be 12 mm

Lap slices should not be used for bar larger than 36 mm.

In steel reinforcement binding wire required is 8 kg per MT.

Lapping is not allowed for the bars having diameters more than 36 mm.

Minimum number of bars for a square column are 4 and for circular column are 6.

Longitudinal reinforcement should not be less than 0.8% and more than 6% of gross C/S.

Weight of rod per meter length = d2/162 where d is the diameter in mm

All reinforcement shall be free from mill scales, loose rust & coats of paints, oil or any other substances.

Main bars in the slabs shall not be less than 8 mm (HYSD) or 10 mm (Plain bars) and the distributors not less than 8 mm and not more than 1/8 of slab thickness.

Advertisements

In case of spacing of bars
Provide the diameter of the bar, if the diameter of the bar are equal.
Provide the diameter of the larger bar, if the diameter are unequal.
5mm more than the nominal maximum size of the coarse aggregate.

Things Site Engineers Must Know

Check out the Unit Weights and Conversion which will be required on construction site here

We at engineeringcivil.com are thankful to Er Vikrant for submitting this construction site check list which is of great use to all civil engineers.

More Entries :
Comments
  • Marimuthu V November 1, 2013 at 11:46 pm

    holow buddies,am having the kind of confusion in rcc structure steel fixing.in that frm the given layout how can I predict myself which 1 type of steel bar should lay first for initiate the structure and further completion.how to get the
    knowledge in that kind of rcc steel fixing works..give me some guidelines..

  • shabab anwer November 7, 2013 at 8:13 am

    what the minimum nd maximum percetage of steel in column nd beam,slab….plz tell me guys

    • karthik.k.v April 10, 2014 at 4:14 am

      0-4% for Slab, 4-8% for beam, 8-12% for footing and 12-16% for column. the percentage is calculated in unit weight of steel i.e 7850. The result, which is calculated in this is for 1 m3 of concrete.

      • venkadeshwaran May 29, 2016 at 6:53 am

        0.12% for slab & footing in case of deformed bars, 0.2% to 4% for beams, 0.8% to 6% for columns

    • Manish Janggid November 16, 2014 at 8:41 am

      it should be 0.6 to 8% of the column or beam or slab.

  • Rajeev Sharma August 23, 2014 at 4:50 am

    Why we not use bar in center of column

  • R K TYAGI September 15, 2014 at 1:13 pm

    How may laps permitted in main and cross bars in a column footing.

  • Vipul Arora September 20, 2014 at 1:36 pm

    Nice work.. Keep it up..!!

  • Murugesan.N October 30, 2014 at 5:42 am

    Can we Have 1.95m length of cantilever slabs on both side supporting by a beam with 8mm dia TMT bars @150mm C/C both sides (top and bottom).Please clarify.

  • asad November 17, 2014 at 11:44 am

    plz tell me how i will find the cut length of steel in circular slab

    • sarankumar August 3, 2016 at 10:12 pm

      U can try frm auto cadd I’n cutting length of circular slab.

  • muniyandialagarsamy November 29, 2014 at 12:35 am

    what is spaceing in chair rod in rebar specification

  • mohsin December 8, 2014 at 6:56 am

    how to calculate the steel rod diameter required for RCC beams

  • Umer Farooq May 28, 2015 at 3:50 am

    in above notes there is point that Lapping is not allowed for the bars having diameters more than 36 mm. what does it mean i cannot understand this because every where lapping is must in rebar.

    • mohammed rizwan November 4, 2015 at 9:28 am

      Because u cannot lap such a bigger dia bars, we can use anchorage bolts to lap them.

    • Ashwinee March 13, 2016 at 8:32 pm

      It should be welded befor going to making a joint

  • amaan July 8, 2015 at 4:38 am

    if we provide more laps in longitudinal reinforcement of deck slab then is it a problem?

  • anjana July 12, 2015 at 2:02 am

    in footing design main reinforcement or distributer steel which lies on bottom

  • jalpit S October 25, 2015 at 2:52 am

    Exactly where overlapping is taken for BEAM , COLUMNS, SLABS.

  • seema rani December 2, 2015 at 11:26 pm

    If the plain bar are used , the area of distribution reinforcement in slab should not be less then 0.12%, 0.15%, 0.18% 0.21, of the gross area of concrete plsss tell

  • Mudessir Abbasi December 13, 2015 at 6:02 am

    Dear sir Please Explain Why We add one Extra Bar in Calculation Of BBS

  • indunil May 30, 2016 at 11:29 am

    hey guys , does any body know a calculation for alternative reinforcements . such as if we are using 12mm and 16mm s insted of using 20mm s , how many bars we has to use and how can we use them . any idea

    • iyke June 19, 2016 at 5:08 pm

      Just calcuate equivalent area of the reinforcing bar to be used

    • Anzar November 8, 2016 at 2:28 am

      Area of steel calculation to be done.

      12 dia bar @ 150 mm spacing as per the drawing.but we do not have 12mm at site in that condition
      we are going for higher dia (16mm)with area of steel calculation.

      step:1

      To find sapcing

      Formula = d*d/s d1=12mm d2=16mm
      s1=150mm s2=?

      d1*d1/s1 = d2*d2/s2

      12*12/150 =16*16/s2

      s2=266.66 mm

      Step:2

      Area of steel calculation

      Formula =3.14*d*d/4

      3.14*12*12/4 = 3.14*16*16
      113.04mm*mm = 200.96mm*mm

      we have to divided by spacing

      133.04/s1 =200.96/s2
      133.04/150 = 200.96/266.66
      0.7536 mm = 0.7536 mm

      Hence the spacing the spacing calculation S2 is correct

      Step : 3

      For sample we are calculating for 4sqm (using 16 dia bar instead of 12mm)

      12mm bar @ 150 mm spacing = 4000/150
      =26.66 ..say 27 nos of 12mm bar @ 150mm spacing

      16mm bar @ 266.66 mm spacing = 4000/266.66
      =15.0003 …say 16 nos of 16mm bar @ 266.66 mm spacing

      Thank you

  • pratik July 30, 2016 at 6:56 am

    lets say there is T12@100c/c to be replaced with T16 due to unavailability of T12.
    so area of T12-113.04
    area of T16-200.96
    no. of T12 in 1 meter = (1000/100)+1 = 11nos.
    area of 11T12 bars = (113.04*11)= 1243.44.
    therefore no of T16 bars req = 1243.44/200.96 = 7
    so the spacing of T16 bars =142.85mm. rounding to 140 c/c.
    so T16 bars can be used 7-T16@140c/c

  • Nivaas August 2, 2016 at 7:01 am

    what is the gauge of binding wire normally using for Tying of reinforcement?

  • MASUM RAZA September 19, 2016 at 5:57 am

    Can any plz tell me easy way to calculate Quantity of Steel for Raft Foundation

  • Dharmvir Singh Chaudhary October 3, 2016 at 6:48 am

    Dear Sir, Please Explain and Calculated Circular Column.

  • Post a comment

1 2 3