April 17, 2024

Mix Design For M55 Grade of Concrete

  • Grade of Concrete : M55
  • Type of Cement : OPC 53 grade confirming to IS 269
  • Maximum Nominal Size Aggregate : 20 mm
  • Minimum Cement content : 380Kg/cum
  • Maximum Water- Cement Ratio : 0.4
  • Workability : 125± 25 mm (slump)
  • Exposure Condition : Moderate (For Reinforced Concrete)
  • Method of Concrete Placing : Pumping or Bucket
  • Degree of Supervision : Good
  • Type of Aggregate : Crushed angular Aggregate
  • Chemical admixture type : Super plasticizers Confirming IS 9103:1999
  • Max cement content: 450kg/cum

2. Material Properties

  • Cement : Ultratech OPC 53 grade confirming to IS 269
  • Specific Gravity of cement : 3.15
  • Chemical Admixture : Fosroc Auromix 400
  • Specific Gravity of Admixture : 1.09
  • Specific Gravity
    • Coarse aggregate
      • 20mm : 2.69
      • 12.5mm : 2.69 
      • Ratio of aggregate: 20mm-50% & 12.5mm-50%
    • Fine aggregate
      • Crushed stone aggregate : 2.6
  • Water: 1
  • Water Absorption
    • Coarse aggregate
      • 12.5mm : 0.54%
      • 20mm : 0.37%
    • Fine aggregate
      • Crushed stone aggregate : 2.35%
  • Free Surface Moisture
    • Fine aggregate : Nil
    • Coarse aggregate: Nil
  • Sieve Analysis
  • Coarse aggregate:
IS Seive Sizes % Passing IS Requirement as per IS 383 Table 2 Ratio Confirming to IS 383 table 2
Single Sized Graded 50% 50%  
  20 mm 12.5 mm 20 mm 12.5 mm   20 mm 12.5 mm Combined 100%
20 95.01 100 85-100 100 100 47.51 50 97.51
12.5 0 99.15 85-100 90-100 0.00 49.58 49.58
10 2.54 51.07 0-20 0 – 45 40 – 85 1.27 25.54 26.81
4.75 0.88 0.42 0-5 0-10 0 – 10 0.44 0.21 0.65
PAN 0 0 0 0 0

Sieve Analysis of Coarse Aggregate, M55 grade of concrete

    • Fine Aggregate: Confirming to grading Zone II of table 4 of IS 383 Note:- as per field trials for pumpable concrete fine aggregate should pass zone II; According to IS 383 clause No. 31.2.2 allows to use crushed stone sand as fine aggregate for concrete .According to IS 383-2016 for crushed stone sand, the permeassible limit on 150 micron IS sieve is increased to20%.
IS Seive Sizes % Passing Ratio River Sand:Msand 0 Combined Passing
0 1 IS 383 Zone II
  R Sand M Sand R Sand M Sand    
4.75 0 100 0 100 90-100 100
2.36 0 85.88 0 85.88 75-100 85.88
1.18 0 58.95 0 58.95 55-90 58.95
600 0 38.87 0 38.87 35-59 38.87
300 0 21.47 0 21.47 8-30 21.47
150 0 9.74 0 9.74 0-10 9.74

Sieve Analysis of Fine Aggregate, M55 grade of concrete

All in aggregate:

IS Seive Sizes 29.5% 29.5% 41% Specification Combined Passing
20mm 12.5mm c sand min-max
40 100 100 100 100-100 100.00%
20 95.01 100 100 95-100 98.53%
4.75 0.88 0.42 100 30-50 41.38%
0.6 0 0 38.87 10-35 15.94%
0.15 0 0 9.74 0-6 3.99%

Sieve Analysis of All in Aggregate, M55 grade of concrete

3. Target Mean Strength 

  • As per MORTH the Target Mean Strength for M55 Grade = 55+14=69Mpa

4. Selection of water/Cement Ratio (W/C)

  • As per the specification max Water/Cement + Binder = 0.4

5. Water content Calculation

Ref Tab 2 , IS 10262 , Maximum water content per cum for 20mm Aggregate = 186 litre for  50 mm slump

= 186 + (0.09 * 186) (add 3% for every 25 mm increase )

= 203lit

Based on trials with super plasticizers, water content reduced by 26%,hence the arrived water content = 150.03lit, So Let us add water 150 lit

6. Cementious content Calculation

Based on experience adopt Water-Cementitious Ratio = 0.34

Cementious content (Cement OPC 53 ) = 441.2

Say Cementitious content = 445 kg/m3

Cement = 445 kg/m3

Based on experience and lab trials, Based on experience and lab trials, super plasticizer = 0.6 %

7. Aggregate content Calculation

Ref Tab 3 of IS 10262 , for Sand Zone II ,  volume of coarse aggregate

per unit vol of total aggregate for 0.5 water-cement ratio = 0.62

Adjust for W/c ratio : Add @ 0.01 for every decrease in 0.05=  0.032

Therefore , corrected proportion = 0.652

Adjust for pumpability , i.e. decrease by 10% = 0.59 %

Based on experience  Considering Volume of coarse aggregate = 0.59

Therefore, Volume of Fine aggregate   = 0.41

8. Mix volume Calculation per cubic meter of concrete

a) Volume of concrete = 1 m3

b)  Volume of cement = (Mass of cement /specific gravity of cement) × 1000 =445/(3.15×1000)= 0.1413 m3

c) Volume of water = (Mass of water /specific gravity of water)× 1000 = 0.150 m3

d) Volume of admixture = (Mass of admixture /specific gravity of admixture)× 1000 = (445×0.6)/(100×1.09×1000)=0.00245 m3

e) Volume of all in aggregate =[a-(b+c+d)] =1-(0.1413+0.150+0.00245)=0.706  

f) Mass of coarse aggregate(CA)

1) 20 mm = e × volume of CA × sp. gravity × % of 20mm × 1000 = 0.706*0.59*2.69*0.5*1000= 560.47kg/m3, Say 561 kg/m3

2) 12 mm = e× volume of CA × sp. gravity × % of 12mm × 1000 = 0.706*0.59*2.69*0.5*1000 = 560.47 kg/m3 Say  560 kg/m3

g) Mass of Fine aggregate = e× volume of FA × sp. gravity × 1000 =0.706*0.41*2.6*1000= 752.9kg/m3 Say  753 kg/m3

9. Details of Mix Design

  • cement = 445 kg
  • 20mm = 561 kg
  • 12mm = 560 kg
  • Crushed stone sand = 753 kg
  • Chemical admixture = 2.67 kg
  • Free Water = 150 kg
  • Water-Cement Ratio = 0.34
  • Concrete density = 2472 kg/m3

Leave a Reply

Your email address will not be published. Required fields are marked *

error: Content is protected !!