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