Project on Concrete Mix Design for various grades of Concrete

CONCRETE MIX DESIGN FOR M 35 GRADE WITH FLY ASH.

grade of designation  : m35

type of cement:opc 43 grade confirming 8112

maximum nominal size of aggregate: 20mm

exposure type: severe

minimum cement content :320 kg/m3

workability :100mm

method of concrete placing: pumplable

type of aggregate : crushed angular

maximum cement content: 450 kg/m3

chemical admixture ; super platisizer

fly ash: confirming to 3812

sp gravity of fly ash: 2.2

sp gr of cement: 3.15

sp gr of fine aggr: 2.61

sp gr of coarse aggr: 2.73

coarse and fine aggr: grade 1

 Target strength 

fck =fck +1.65 S

        35+1.65*5 =43.25N/MM2

water cement ratio

from table 5,IS 456- 2000, for sever exposure condition w/c ratio  = 0.45

from IS 10262-2019, for targeth strength 43.25n/mm2 w/c ratio =0.40

water content

maximum water content= 186 lit

slump for 100 mm water=186+6/100*186=197.16kg/m3

super plastisizer reduces 29% of water content

      71/100*197.16=139.9836~ 140kg/m3

calculation of cementious material (cement+ fly ash)

w/c ratio =0.40

cementious  material(cement + fly ash)= 140/ 0.4= 350 kg /m3

from IS 456 ,minimum cement for severe  exposure condition= 320 kg/m3

                               350 kg/m3>320 kg/m3 .hence ok

proportion of fly ash

 increase cementious material upto 10%

 cementious material content= 350*1.1o= 385 kg/m3

 water content=140 kg/m3

w/c ratio= 140/385 =0.363

fly ash @30% of  total cementious material = 385*30%=115.5kg/m3

                        fly ash= 115.5

                          opc cement= 385-115.5= 269.5 kg/m3

volume of coarse and fine aggregate

from table 3 of IS 10262 2009

Volume of coarse aggre corresponding to 20 mm size of aggre 

               w/c   =  0.60

here w/c = 0.40

 volume of course aggre for 0.40= 0.62

for pumpable concrete  10% reduction

volume of course aggr= 0.62*.9= 0.56

volume of fine aggr= 1-0.56=0.44 

mix calculation :

a          volume of concrete= 1m3

b           volume of cement= mass of cement/ sp gr of cement*i/1000

                                           269.5/3,15*1/1000 = 0.085 m3

c             volume of fly ash= mass of ash/sp gr of ash*1/1000

                                           115.5/2.2*1/1000=0.0525 m3

d             volume of water=  140/1000= .140 m3

e              volume of superplastizer =7.7/1.145*1/1000= 0.0067m3 

f              volume of aggr (fa+ ca) =a-(b+c+D+e)= 0.7158m3

g              mass of corse aggr= f*volume of corse aggr* sp gr of corse aggr*1000

                                               0.7158*0.56*2.73* 1000=1094kg

h               mass of fine aggr= f* volume of fine aggr * sp gr og fine aggr

                                            0.7158*0,44*2.61*1000= 822kg

mix proportion

 cement= 269,6 kg

fly ash=115.5 kg

coarse aggr=1094 kg

fine aggr= 822kg

admixture =7 kg

 w/c  =0.4

 2   mix design for M50 grade

grade of designation  : M50

type of cement:opc 43 grade confirming 8112

maximum nominal size of aggregate: 20mm

exposure type: severe

minimum cement content :320 kg/m3

workability :125mm

method of concrete placing: pumplable

type of aggregate : crushed angular

maximum cement content: 450 kg/m3

chemical admixture ; super platisizer

sp gr of cement: 3.15

sp gr of fine aggr: 2.61

sp gr of coarse aggr: 2.73

coarse and fine aggr: grade 1

 Target strength 

fck =fck +1.65 S

        50+1.65*5 =58.25 N/MM2

water cement ratio

from table 5,IS 456- 2000, for sever exposure condition w/c ratio  = 0.45

from IS 10262-2019, for targeth strength 58.25N/mm2 w/c ratio =0.34

water content

maximum water content= 186 lit

slump for 125 mm water=186+9/100*186=202.74kg/m3

super plastisizer reduces 29% of water content

      71/100*202.74=143.94

calculation of cement content

w/c ratio =0.40

= 140/ 0.4= 359.8 kg /m3

from IS 456 ,minimum cement for severe  exposure condition= 320 kg/m3

                               359.8 kg/m3>320 kg/m3 .hence ok

volume of coarse and fine aggregate

from table 3 of IS 10262 2009

Volume of coarse aggre corresponding to 20 mm size of aggre 

               w/c   =  0.60

here w/c = 0.45

actual w/c =0.45-0.40=0.05

 volume of course aggre for is 0.60+0.01=0.61

for pumpable concrete  10% reduction

volume of course aggr= 0.61*.9= 0.549

volume of fine aggr= 1-0.549=0.451

mix calculation :

a          volume of concrete= 1m3

b           volume of cement= mass of cement/ sp gr of cement*i/1000

                                           359.8/3.15*1/1000 = 0.114 m3

c                        volume of water=  143.94/1000= 0.143 m3

d              volume of superplastizer =7.19/1.145*1/1000= 0.0062m3 e

e              volume of aggr (fa+ ca) =a-(b+c+D+)= 0.737m3

f              mass of corse aggr= f*volume of corse aggr* sp gr of corse aggr*1000

                                               0.737*0.549*2.73* 1000=1104.5 kg

g               mass of fine aggr= f* volume of fine aggr * sp gr og fine aggr

                                            0.737*0.451*2.61*1000= 867kg

mix proportion

 cement= 359.8 kg

coarse aggr=1094 kg

fine aggr= 867kg

admixture =7 kg

 w/c  =0.4