Construction Concrete

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Mix Design - Inputs and Outputs for 'Construction Concrete'    
  Tutor Inputs Tutor Outputs
 
             
Strength Input 1 Specified 28 day Characteristic Strength (see table 1) 45 MPa Output 1 F ratio (no. of std deviations betw target and char strength) 1.64 (see fig 1)
  Input 2 Coefficient of Variation (consult factory records, or see table 2) 12.0 % Output 2 Target strength 56 MPa
  Input 3 % failures allowed 5 % Output 3 #REF!    
          Output 4 Standard deviation 6.7 MPa
w : c ratio Input 4 % fly ash (balance is clinker) 15 % Output 5 % clinker 85 %
  Input 5 max w:c for capilliary discontinuity 0.70   Output 6 Water : cement ratio  (from fig 2) 0.46  
  Input 6 % S03 in soil 0.1 % Output 7 Corresponding Water : ratio (for SO3 in soil) 0.70  
  Input 7 % S03 in ground water 0.2 % Output 8 Corresponding Water : ratio (for SO3 in groundwater) 0.70  
  Input 8 Acidic ground or water (Yes = 1, No = 0) 0   Output 9 Corresponding Water : ratio (for acid in water or ground) 0.70  
  Input 9 Soft Water (Yes = 1, No = 0) 0   Output 10 Corresponding Water : ratio (for soft water) 0.70  
          Output 11 Trial water:cement ratio 0.46  
Superplasticizer Input 10 % addition by weight of total cementitious content 0.8 %        
  Input 11 Water reduction capability of superplasticizer at above dosage 20 %        
  Input 12 RD of superplasticizer 1.19   Output 12 Trial Superplasticizer addition 2.78 kg/m3
Water Input 13 Water requirement of sand (or consult table 3 for options) 210 litres Output 13 Adjustment for slump relative to 75mm slump (from fig 3) -9 litres
  Input 14 required slump 40 mm Output 14 Adjustment for stone size (see fig 4) 0 litres
  Input 15 stone size (6.7, 9.5, 13.2, 19.0 26.5, 37.5, 75) 19 mm Output 15 Adjustment for superplasticizer -40 litres
  Input 16 RD water 1   Output 16 Trial Water Requirement 160 litres/m3
Cementitious Input 17 RD cement 3.14   Output 17 Total Cementitious Content 348 kg/m3
  Input 18 RD fly ash 2.2   Output 18 Trial Cement content (Cem 1) 295 kg/m3
          Output 19 Trial Fly Ash content 52 kg/m3
Stone Input 19 Compacted bulk density (CBD) 1500 kg/m3 Output 20 K factor (from fig 5) 0.97  
  Input 20 Fineness modulus (FM) 1.9   Output 21 corresponding stone constent 1164 kg/m3
  Input 21 Vibration : input a 1 for hand, input a 2 for power 2   Output 22 % increase in stone for fly ash (from fig 6) 2.8 %
  Input 22 RD stone 2.99   Output 23 Trial Stone content 1196 kg/m3
  Input 23 Adjustment (0 kg if OK, -100kg if too stony, +100 kg if too sandy) 0 kg        
Air Input 24 % air content (entrapped air) 1 % Output 24 Trial Air Content 10 litres/m3
Sand Input 25 % by mass of graded-sand 70 % Output 25 CHECK : output 25 + output 27 = 100% : CORRECT    
  Input 26 RD of graded-sand 2.81   Output 26 Effective RD of sand 2.76  
  Input 27 % by mass of filler-sand 30 % Output 27 Total Sand content 855 kg/m3
  Input 28 RD of filler-sand 2.65   Output 28 Trial Graded-Sand Content 598 kg/m3
          Output 29 Trial Filler-Sand Content 256 kg/m3
          Output 30 Total Mass of Mix 2561 kg/m3