Quantity Estimate

[maheshv]

Starting off with a new discussion topic based on my self learning, please comment.

Cement
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Identifying cement quantity for PCC or RCC work,
1 bag of cement is 50kg
50kg is 1.25CFT
1bag = 1.25cft
1cft = 0.8bag

So for example you need 100CFT of RCC with ratio of 1:2:3 (cement:sand:jelly/coarse aggregate)
Cement will be 1/(1+2+3) of 100CFT or 16CFT
16CFT of cement is 13bags (0.8*16cft)
similarly you can calculate sand and jelly

Steel
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Each bundle of steel is approximately 50 to 55kg irrespective of thickness (mm) size
so if your engg mentions you need 400kg of 8mm rods, you should receive 8bundles from dealer/retailer

In Bangalore, generally for 1000 SFT RCC work, you need 3 ton steel

I am not sure how to calcualte steel required for a structure, would be interesting to know the same.

[maheshv]

Steel Estimate based on drawing
http://in.answers.yahoo.com/question/in ... 658AAGIz9u
Measure the length of bars for different dia steels...
Multiply the length of bars with respective cross sectional areas...to get volume.
Multiply the total volume by 7850 to get the weight in kgs...

[maheshv]

http://answers.yahoo.com/question/index?qid=20090308135746AAmwbLH
It depends on whether you are talking about a reinforced concrete (RC) structure or a steel structure.
In a RC structure you multiply the No. of bars by their weight per metre.
In a steel structure you either look up the weight per metre in a handbook or calculate the volume.
In all cases the density of steel is 7850kg/m3

[krish]

Thanks Mahesh for the info..

[maheshv]

Welcome Krish,

I was researching further and found better formula

http://libraryvirtual.com/calculating-r ... ut-tables/
Calculate the weight of steel reinforcement diameter 16 with a length of 12 meters?
Heavy iron bars = 0.006165 x d2 x L … (Kg)
where:
d = diameter of reinforcement (mm)
L = length of reinforcing rod (m)

heavy iron Ø16 = 0.006165 x 162 x 12 = 18.93 kg

[girishd]

Thanks for sharing Mahesh.

Does anyone know a way to estimate the the following for a 10 sqft wall (9" thickness)?
1. Num of bricks
2. Cement/Sand for raising the wall
3. cement/said for Plastering