Concrete Mix Proportion following IS 10262
STEP 1: Stipulations for Proportioning
1. Grade Designation:
Select
M 10
M 15
M 20
M 25
M 30
M 35
M 40
M 45
M 50
M 55
2. Type of cement: OPC 43 grade IS 8112
2'. Type of mineral admixture (if any):
Select
No
Fly ash - IS 38I2 (Part I)
3. Max. Nom. Size of aggregate (mm):
Select
20
10
40
4. Min. cement content (kg/cum): 300
5. Max. water/cement ratio: 0.55
6. Workability (mm):
7. Exposure condition:
Select
Mild
Moderate
Severe
Very severe
Extreme
8. Method of concrete placing: Pumping
9. Degree of supervision: Good
10. Type of aggregate:
Select
Crushed Angular Aggregate
Sub-angular aggregates
Gravel with some crushed particles
Rounded Gravel
11. Maximum cement content (kg/cum): 450
Admixture is used:
Yes
No
12. Chemical admixture type: Superplasticizer
13. Water reduction thanks to admixture (%):
14. Admixture dosage (%) (admixture volume/cement (or cementitious ) mass):

STEP 2: Test Data of Materials
1. Cement used: OPC 43 grade IS 8112
2. Sp. Gravity of cement: *
3. Chemical admixture: As above
4. Specific Gravity of: Coarse Aggregate: *
Fine Aggregate: *
5. Water absorption: Coarse Aggregate: *
Fine Aggregate: *
6. Free (surface) moisture: C.A= NIL F.A= NIL
7. Sieve analysis: CA See gradation table
FA confirming to grade
Select
Zone I
Zone II
Zone III
Zone IV
of Table 4 of IS : 383
8. Sp. Gravity of fly ash: *

STEP 3: Target Strength for Mix Proportioning
f'ck = fck + 1.65s
where
f'ck = target average compressive strength at 28 days
fck = characteristic compressive strength at 28 days, and
s = standard deviation.
From Table 1 , with concrete strength of 10 MPa, standard deviation s = 3 N/sqmm.
Therefore, target strength = 10 + 1.65*3 = 15.8
Sl. No.
Grade of Concrete
Assumed Std. Dev. (N/sqmm)
1
2
3
i
10
3.5
ii
15
iii
20
4.0
iv
25
v
30
5.0
vi
35
vii
40
viii
45
ix
50
x
55

STEP 4: Selection of w/c ratio
Max. w/c ratio = 0.55 From Table 5 of IS 456
Sl.No.
Exposure
PCC
RCC
1
Mild
220
0.60
300
0.55
M20
2
Moderate
240
0.60
M15
300
0.50
M25
3
Severe
250
0.50
M20
320
0.45
M30
4
Very Severe
260
0.45
M20
340
0.45
M35
5
Extreme
280
0.40
M25
360
0.40
M40

Adopting w/c ratio as
If value is not set, adopting value is assumed =
STEP 5: Selection of water content
Maximum water content =
(for Aggregate: 20 mm and type of aggregate: Crushed Angular Aggregate )
Estimated water content for slump mm = (litres)
As superplasticizer is used, the water content can be reduced up % as above. The arrived water content =
(litres)
STEP 6: Calculation of Cement Content
Water-Cement ratio =
Cement content =
Now, to proportion a mix containing fly ash the following steps are suggested:
1. Decide the percentage fly ash to be used based on project requirement and quality of materials
2. In certain situations increase in cernentitious material content may be warranted. The decision on increase in cementitious material content and its percentage may be based on experience and trial
Enter percentage of increase of cementitious content
otherwise it is assumed with increase of 10 percent cementitious material content.
Enter percentage of fly ash content of total cementitious content
otherwise it is assumed with replacement of 30 percent cementitious material content.
Cementitious content (cement + fly ash ) =
So the water-cement ratio become =
Fly ash at % of total cementitious material content = (kg/m3)
Cement (OPC)= (kg/m3)
Saving of cement while using fly ash = (kg/m3)
Fly ash being utilized = (kg/m3)
STEP 7: Proportion of Volume of Coarse Aggregate And Fine Aggregate Content
1. From Table 3 , Vol. of CA corresponding to coarse aggregate size mm and Fine Aggregate
for water/cement ratio of 0.5:
2. In the present case, water/cement ratio =
Volume of Coarse Aggregate is required to be adjusted to change the Fine Aggregate content.
Therefore, the adjusted volume of Coarse Aggregate for the present WC =
3. For Pumpable concrete, these values should be reduced by 10% (as per cl.4.4.1 of 10262)
Therefore, volume of Coarse Aggregate =
volume of Fine Aggregate =
Nominal MSA
Vol. of CA per Unit Volume of Total Aggregate for Different Zones of FA
mm
IV
III
II
I
10
0.50
0.48
0.46
0.44
20
0.66
0.64
0.62
0.60
40
0.75
0.73
0.71
0.69

STEP 8: Mix Calculations
The mix calculations per unit volume of concrete shall be as follows:
1. Vol. of Concrete (cum) = 1
2. Vol. of Cement (cum) (Mass of cement/ Spec.Gravity of Cement)x1/1000 =
2'. Vol. of Fly Ash (cum) (Mass of fly ash/ Spec.Gravity of fly ash)x1/1000 =

3. Vol. of water (cum) =
4. Vol. of Chemical Admixture =
5. Vol. of All-in-aggregate = =
6. Mass of Coarse Aggregate = (5) x Vol. of CA x Sp.grav. of CA x 1000 =
7. Mass of Fine Aggregate = (5) x Vol. of FA x Sp.grav. of FA x 1000 =
STEP 9: MIX SUMMARY
1. Cement weight (kg) =
1'. Fly Ash weigth (kg) =

2. Water weight (kg) =
3. Chemical Admixture (litres) =
4. Mass of Coarse Aggregate (kg) =
5. Mass of Fine Aggregate (kg) =
STEP 1: Stipulations for Proportioning

1. Grade Designation:

2. Type of cement: OPC 43 grade IS 8112

2′. Type of mineral admixture (if any):

3. Max. Nom. Size of aggregate (mm):

4. Min. cement content (kg/cum): 300

5. Max. water/cement ratio: 0.55

6. Workability (mm):

7. Exposure condition:
8. Method of concrete placing: Pumping
9. Degree of supervision: Good
10. Type of aggregate:
11. Maximum cement content (kg/cum): 450
Admixture is used: Yes No
STEP 2: Test Data of Materials
1. Cement used: OPC 43 grade IS 8112
2. Sp. Gravity of cement:
3.15
*
3. Chemical admixture: As above
4. Specific Gravity of: Coarse Aggregate:
* Fine Aggregate:
*
5. Water absorption: Coarse Aggregate:
* Fine Aggregate:
*
6. Free (surface) moisture: C.A= NIL F.A= NIL
7. Sieve analysis: CA See gradation table
FA confirming to grade of Table 4 of IS : 383
STEP 3: Target Strength for Mix Proportioning
f’ck = fck + 1.65s
where
f’ck = target average compressive strength at 28 days
fck = characteristic compressive strength at 28 days, and
s = standard deviation.

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12
JAN
2018