Presentation on "Concrete Mix Designing" for Minor Project.

1. By

2. Introduction
• Concrete Mix Design means, determination of
the proportion of the concrete ingredients i.e.
Cement, Water, Fine Aggregate, Coarse
Aggregate which would produce concrete
possessing specified properties such as
workability, strength and durability with
maximum overall economy.

3. Types of Concrete Mixes
1. Nominal Mixes –
• These mixes are of fixed cement-aggregate ratio.
• These offer simplicity and under normal circumstances.
• Have a margin of strength above that specified.
2. Standard Mixes –
• The minimum compressive strength has been included by
IS-456:2000 in many specifications. These mixes are
termed standard mixes.
• E.g.: M10, M15, M20, etc.
3. Designed Mixes -
• In these mixes the performance of the concrete is specified
by the designer but the mix proportions are determined by
the producer of concrete, except that the minimum cement
content can be laid down.

4. Methods of Concrete Mix Design
• American Concrete Institute Method (ACI
Method)
• Road Note Number 4 Method
• DOE Method
• Indian Standard Method (IS Method)

5. Indian Standard Recommended
Method Of Concrete Mix Design
(IS 10262 - 2009)
Data Required:
• Grade of Concrete
• Slump required in mm
• Degree of Site Control
• Type of Exposure
• Grade of Cement

6. Workability
(Clause 7.1, IS:456-2000)

7. Degree of Site Control
(Table 8, IS:456-2000)

8. Type of Exposure (Table 3, IS:456-2000)

9. Concrete Mix Design steps
IS - 10262 : 2009

10. Step1 Target Mean Strength
• Target mean strength
ft = fck+ k x s
ft = 30+1.65 x 5
ft = 38.25 N/mm2
ft = target mean compressive strength at 28 days
fck = Characteristic compressive strength of
concrete at 28 days,
k = usually 1.65 as per IS:456-2000
s = standard deviation.

11. Step2 Selection of water/cement ratio
• Using graph
W
C
= 0.38

12. Step2 Selection of water/cement ratio
But from table – 5, IS-456:2000

13. Step2 Selection of water/cement ratio
Considering moderate exposure,
Max w/c = 0.5
Hence w/c = 0.38
w/c = 0.38

14. Step3 Selection Of Water Content.
• From table – 2, IS-10262:2009
(For 20mm nominal max. size of aggregate & 25 to
50mm slump)
Max WC = 186 kg/m3
# Correction for slump in water content (according to
clause 4.2, IS:10262)
Slump = 100 mm
Correct WC for 100 mm slump = 186 + 6%
= 197.16 kg
197 kg of water per m3 of concrete

15. Step4 Calculation Of Cement Content
W/C = 0.38
C =
197
0.38
= 518.42 kg/m3
Min CC = 300 kg/m3 concrete
(From table: 5, IS:456)
Hence, C = 518.42 kg/m3
518.42 kg of Cement per m3 of Concrete

16. Step 5: Selection of Proposition of
Volume of Coarse Aggregate
From table 3,(IS-10262:2009) for zone IIIrd of F.A.
Maximum size of aggregate = 20 mm.
Vol. of CA per unit vol. of total aggregate = 0.64
# For 0.1 decrease in w/c & increase in CA by 0.02
Applying correction of 0.024
Vol. of CA = 0.64 + 0.024
=0.664m3
Total aggregate = 1
CA = 0.664m3
FA = 0.336m3

17. Step6 Mix Calculation Results:
Mass of
Cement
Water F.A. C.A.
518.42 197 586.36 1161.76
1 0.38 1.13 2.24
Ratio Obtained
1 : 1.13 : 2.24

18. Thanks
For
Hearing