April 18, 2024

Mix Design of M50 Grade of Concrete with OPC Cement

1. Mix stipulation for ingredients of concrete

  • Grade of Concrete : M50
  • Type of Cement : OPC 53 grade confirming to IS 269
  • Maximum Nominal Size Aggregate : 20 mm
  • Minimum Cement content : 400Kg/cum
  • Maximum Water- Cement Ratio : 0.4
  • Workability : 125 ± 25 mm (slump)
  • Exposure Condition : Moderate for RCC
  • 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

2. Material Properties

  • Cement : Ultratech OPC 53 grade confirming to IS 269
    • Specific Gravity of cement : 3.15
  • Chemical Admixture : BASF Master Glenium Sky 8511
    • Specific Gravity of Admixture : 1.07
  • Specific Gravity
    • Coarse aggregate
      • 20mm : 2.66
      • 12.5mm : 2.64
      • Ratio of aggregate: 20mm-50% & 10mm-50%
    • Fine aggregate
      •   Crushed stone aggregate : 2.59
    • Water: 1
  • Water Absorption
    • Coarse aggregate
      • 20mm : 0.37%
      • 12.5mm : 0.54%
    • Fine aggregate
      •   Crushed stone aggregate : 2.35%
    • Free Surface Moisture
      • Fine aggregate : Nil
      • Coarse aggregate: Nil
    • Sieve Analysis
      • Coarse aggregate:
IS Seive Sizes% PassingIS Requirement as per IS 383 Table 2RatioConfirming to IS 383 table 2
Single SizedGraded50%50%
20 mm12.5 mm20 mm12.5 mm20 mm12.5 mmCombined 100%
2095.0110085-10010010047.5055097.51
12.5099.1585-10090-1000.0049.57549.58
102.5451.070-200 – 4540 – 851.2725.53526.81
4.750.880.420-50-100 – 100.440.210.65
PAN00000
Sieve Analysis of Coarse Aggregate, M50 grade 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  % PassingRatio RSand:MsandSpecificationCombined Passing  
01IS 383 Zone II  
R SandM SandR SandM Sand
4.750100010090-100100
2.36085.88085.8875-10085.88
1.18058.95058.9555-9058.95
600038.87038.8735-5938.87
300021.47021.478-3021.47
15009.7409.740-109.74
Sieve Analysis of Fine Aggregate, M50 grade concrete

All in aggregate:

IS Seive Sizes28.5%28.5%43%SpecificationCombined Passing
20mm12.5mmc sandmin-max
40100100100100-100100.00%
2095.0110010095-10098.58%
4.750.880.4210030-5043.37%
0.60038.8710-3516.71%
0.15009.740-64.19%
Sieve Analysis of All in Aggregate, M50 grade concrete

3. Target Mean Strength and Mix Proportioning

  • As per MORTH the Target Mean Strength for M-50 Grade = 63 Mpa

4. Target Mean Strength and Mix Proportioning

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

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

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 )

= 203 lit

Based on trials with super plasticizers, water content reduced by 33%,hence the arrived water content = 135.84lit, So Let us add water 136 lit

6. Cementious content Calculation

Water-Cementitious Ratio = 0.31

Cementious content (Cement OPC 53 ) = 439

Say Cementitious content = 440 kg/m3 

Cement = 440 kg/m3 

Based on experience and lab trials, Based on experience and lab trials, super plasticizer = 0.57 %

7. Calculation 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=  0.038

Therefore , corrected proportion = 0.658

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

Based on experience  Considering Volume of coarse aggregate = 0.57

Therefore, Volume of Fine aggregate   = 0.43  

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 = 0.1397 m3

c) Volume of water = (Mass of water /specific gravity of water)× 1000 = 0.136 m3

d) Volume of admixture = (Mass of admixture /specific gravity of admixture)× 1000 = 0.00234 m3

e) Volume of all in aggregate =[a-(b+c+d)] = 0.72 m3

f) Mass of coarse aggregate(CA)  

1) 20 mm = e × volume of CA × sp. gravity × % of 20mm × 1000 = 0.72*0.57*2.65*0.5*1000 = 545.27 kg/m3, Say 545 kg/m3

2) 12 mm = e× volume of CA × sp. gravity × % of 12mm × 1000 = 0.72*0.57*2.63*0.5*1000 = 541.16 kg/m3, Say 541 kg/m3

g) Mass of Fine aggregate = e × volume of FA × sp. gravity × 1000 0.72*0.43*2.59*1000 = 804.06 kg/m3 Say  804 kg/m3

9. Details of Mix Design

  • cement = 440 kg
  • 20mm = 545 kg
  • 12mm = 541 kg
  • Crushed stone sand = 804 kg
  • Chemical admixture = 2.51 kg
  • Free Water = 136 kg
  • Water-Cement Ratio = 0.31
  • Concrete density = 2469 kg/m3

Leave a Reply

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

error: Content is protected !!