BlogFor BusinessTalk to a counsellor
CoursesIIT ProgramsPlacementsLog in
BlogFor Business
Talk to a counsellor
Challenge

Project on Concrete Mix Design for various grades of Concrete

CChisti Shaikh27 Jul 2022

Calculate the Concrete Mix Design for M35 grade concrete with fly ash are following

Mix design for M35 grade concrete with fly ash.

STEP 1- Stipulation for proportion

  • Grade of design - M35
  • Type of cement - OPC 43 taken from the IS 8112
  • Type of mineral admixture - fly Ash
  • Maximum nonimal size of3 aggregate - 20MM
  • Minimum cement content - 320kg/m^3 from IS 456-2000 ( table no 5 ).
  • Maximum water cement ratio - 0.45 from (table no 5 IS 456-2000) due to exposure to condition
  • Workability - 100 mm slump value of pumpable concrete
  • Exposure condition - Severe for reinforcement concrete
  • Type of aggregate - crushed aggregate
  • Maximum cement content - 450 kg/m^3
  • Chemical admixture type - superplasticizer
  • Method of concrete placing - pumping

STEP 2

  • Cement used - 43 grade. From IS 8112
  • Specific gravity of cement - 3.15
  • Fly ash - conforming IS 3812 part 1
  • Specific gravity of fly ash - 2.2
  • Chemical admixture - super plasticizer taken IS 9103
  • Specific gravity of course aggregate - 2.74.
  • Specific gravity of fine aggregate - 2.74
  • Water absorption - coarse aggregate - 0.5% fine aggregate. - 1%
  • Free surface moisture - Nil

STEP 3

To find the target mean strength for mix proportion

ft = fck + 1.65*S

= 35 + 1.65* 5

= 43.25 N/mm^2

where fck is compressive strength and S denotes the deviation

STEP 4

  • Selection of water cement ratio - Maximum water cement ratio - 0.45 for severe condition taken from the IS 456- 2000 W/C ratio - 0.4 is less than 0.45 hence it is ok

STEP 5

  • Calculation of water content Water content for 20mm aggregate = 186 liter taken from table no 5 IS 1026- 2009 , for 25mm and 50mm slump range. For 100mm = 186+(6/100)*186. = 197 liters
  • And water content reduced upto 30 % and trial water content reduction of 29% is achieved with plastercizer
  • water content = 197*0.71= 140 liters

STEP 6

  • Calculation of cement content Water cement ratio - 0.4 ( cement + flyash ) = 140/0.4=350kg/mm^3 from IS 456-2000 table no 5 severe exposure is 320kg.mm^3 then hence it is ok Percentage of fly ash depends on project requirement and quality of material.
  • In this increase 10% of cementitious material content Cementitious material content - 140 kg.mm^3 water cement ratio = 140/385 = 0.364.
  • fly ash at 30 % total cementitious material content 35-30% = 385 - 115 = 270.
  • With uses of fly ash the cement get utlized. 350- 270 = 80kg.mm^3
  • Fly ash beign utilzed = 115 kg.mm^3

STEP 7

  • Calculate the volume of coarse aggregate and fine aggregate. From IS 1026-2009 the volume of coarse aggregate for 20mm size of aggregate and fine aggregate zone 1 for water cement ratio is 0.6 But, this case we have water cement ratio is 0.4 Therefore the volume of coarse aggregate needs to be increased to decrease fine aggregate content.
  • If water cement ratio is lowered by 0.1 then volume of coarse aggregate gets increased by 0.02
  • Hence correct value of coarse aggregate water cement rati is 0.64 .
  • But for pumpable concrete it reduced by 10%
  • Volume of coarse aggregate - 0.64*0.9 = 0.576
  • Volume of fine aggregate - 1 - 0.576 = 0.42

STEP 8

  • MIX CALCULATION For per unit volume of concrete is 1m^3
  • 1 volume of cement = mass of cement / specific gravity of cement * 1/1000 =270/3.15 *1/1000 = 0.086m^3
  • 2 volume of Fly ash - Mass of fly ash / specific gravity of flyash *1/1000 - 115/2.2*1/1000 = 0.052 m^3
  • 3 volume of water = mass of water / specific gravity of water *1/1000 =140/1*1/1000 = 0.140 m^3
  • 4 volume of chemical admixture - mass of admixture / specific gravity of admixture * 1/1000 = 7.6/1.14*1/1000 = 0.006m^3
  • 5 Volume of aggregate fine and coarse aggregate - a-(b+c+d+e) = 1-(0.086+0.052+0.140+0.006) = 0.716 m^3
  • 6 Mass of coarse aggregate = F* volume of coarse aggregate * specific gravity of coarse aggregate *1000 =0.716*0.576*2.74*1000 = 1130 kg.m^3
  • 7 Mass of fine aggregate = F* volume of fine aggregate *specific gravity of fine aggregate *1000 =0.716*0.424*2.74*1000 = 831kg.m^3

STEP 9

  • 1 cement - 270 kg/m^3
  • 2 fly ash - 115 kg/m^3
  • 3 water - 140 kg/m^3
  • 4 fine aggregate - 831 kg/m^3
  • 5 coarse aggregate - 1130 kg/m^3
  • 6 chemical admixture -7 kg/m^3
  • 7 water cement ratio - 0.364

STEP 10

  • The slump shall be measured and water content and admixture shall be adjusted for required slump.

STEP 11

  • Variation of 10% of wc ratio is carried by out a using two graph between the water cement ratio.
  • RESULT Mix design for M35 grade of concrete with fly ash is 1: 2.15 : 2.94

Calculate the Concrete Mix Design for M50 grade concrete without Fly ash

Mix design for M50 grade concrete.

STEP 1- Stipulation f or proportion

  • Grade of design - M50 • type of cement - OPC 43 taken from the IS 8112
  • Maximum nonimal size of3 aggregate - 20MM
  • Minimum cement content - 320kg/m^3 from IS 456-2000( table no 5 ).
  • Maximum water cement ratio - 0.45 from (table no 5 IS 456-2000) due to exposure to condition
  • Workability - 100 mm slump value of pumpable concrete
  • Exposure condition - Severe for reinforcement concrete
  • Type of aggregate - crushed aggregate
  • Maximum cement content - 450 kg/m^3
  • Chemical admixture type - superplasticizer
  • Method of concrete placing - pumping

STEP 2 -

  • Cement used - 43 grade. From IS 8112
  • Specific gravity of cement - 3.15
  • Chemical admixture - super plasticizer taken IS 9103
  • Specific gravity of course aggregate - 2.74.
  • Specific gravity of fine aggregate - 2.74
  • Water absorption - coarse aggregate - 0.5%
  • Fine aggregate. - 1%
  • Free surface moisture - Nil
  • Sieve analysis coarse aggregate IS sieve analysis in mm of coarse aggregate in fraction % for different fraction IS 383 table 2 For fine aggregate conforming the grading zone 1 table 4 IS 383

STEP 3

To find the target mean strength for mix proportion

ft = fck + 1.65*S

= 50+ 1.65* 5

=58.25N/mm^2

where fck is compressive strength and S denotes the deviation

STEP 4

  • Selection of water cement ratio - Maximum water cement ratio - 0.45 for severe condition taken from the IS 456- 2000 W/C ratio - 0.4 is less than 0.45 hence it is ok

STEP 5

CALCULATION OF WATER CEMENT RATIO

  • Water content for 20mm aggregate = 186 liter taken from table no 5 IS 1026- 2009 , for 25mm and 50mm slump range.
  • For 100mm = 186+(6/100)*186= 197 liters
  • And water content reduced upto 30 % and trial water content reduction of 29% is achieved with plastercizer
  • water content = 197*0.71= 140 liters

STEP 6

CALCULATION OF CEMENT CONTENT

  • Water cement ratio - 0.4(cement content) = 140/0.4 = 350kg/mm^3 from IS 456-2000 table no 5 severe exposure is 320kg.mm^3 then hence it is ok

STEP 7

  • Calculate the volume of coarse aggregate and fine aggregate. From IS 1026-2009 the volume of coarse aggregate for 20mm size of aggregate and fine aggregate zone 1 for water cement ratio is 0.6 But, this case we have water cement ratio is 0.4 Therefore the volume of coarse aggregate needs to be increased to decrease fine aggregate content.
  • If water cement ratio is lowered by 0.1 then volume of coarse aggregate gets increased by 0.02 Hence correct value of coarse aggregate water cement rati is 0.64 .
  • But for pumpable concrete it reduced by 10% Volume of coarse aggregate - 0.64*0.9 = 0.576 Volume of fine aggregate - 1 - 0.576 = 0.42

STEP 8 -

MIX CALCULATION For per unit volume of concrete is 1m^3

  1. volume of cement = mass of cement / specific gravity of cement * 1/1000 = 350/3.15 *1/1000 = 0.111m^3
  2. volume of water = mass of water / specific gravity of water *1/1000 = 140/1*1/1000 = 0.140 m^3
  3. volume of chemical admixture - mass of admixture / specific gravity of admixture * 1/1000 = 7.6/1.14*1/1000 = 0.006m^3
  4. Volume of aggregate fine and coarse aggregate - a-(b+c+d) = 1-(0.086+0.140+0.006) = 0.743 m^3
  5. Mass of coarse aggregate = F* volume of coarse aggregate * specific gravity of coarse aggregate *1000 = 0.743*0.576*2.74*1000 = 1173 kg.m^3
  6. Mass of fine aggregate = F* volume of fine aggregate *specific gravity of fine aggregate *1000 = 0.743*0.424*2.74*1000 = 863kg.m^3

STEP 9

  • MIX CALCULATION 1 cement - 350 kg/m^3 2 water - 140 kg/m^3 3 fine aggregate - 863kg/m^3
  • 4 coarse aggregate - 1173 kg/m^3 5 chemical admixture - 7 kg/m^3
  • 6 water cement ratio - 0.4

STEP 10

  • The slump shall be measured and water content and admixture shall be adjusted for required slump.
  • The mix proportion shall be worked for actual water content. And the checked3 the durability.

STEP 11

  • Variation of 10% of wc ratio is carried by out a using two graph between the water cement ratio.
  • The graph between three water cement ratio are corresponding strength of shall be plotted to work out mix proportion for given target strength and durability. RESULT Mix design for M50 grade of concrete is 1: 2.46 : 3.35
Your portfolio, next

Ship work like this
in your own course.

Talk to a career counsellor

Free 20-minute call. We'll map the right course to where you want to work.

By submitting you agree to our Terms and Privacy Policy.