Project on Concrete Mix Design for various grades of Concrete
Aim to calculate the concrete mix design for m35 grade concrete with flyash and m50 grade concrete with out flyash
introduction
concrete mix design is the method of finding the precise propotion of cement, sand and aggregates to concrete to achieve the target strength in structures
concrete mix design is the sand , cement and aggregtaes the design is requirements of concrete strength
the first part deals with m35 grade concrete with flash ash as a part of it m50 rade concrete with out fly ash.
Equation
target mean strength= f'ck+fckxs
where
f'ck=average mean comoressive strength at 28days
fck=target mean strngthof compressive at 28 days
s= standard deviation
cement content
cement content=watercontent/water-cement ratio
volume calculation
a volume of concrete=1m3
b volume of cement=massof cement/specific gravityof cemnt x1000
c volume of water=massof water/specific gravity ofwaterx1/1000
d volume of chemical admixtures=mass of addmixture/specific gravity of admixturex1000
e volume of all in aggregates=a-b+c+d
f mass of coarse aggregate=ex volume of coarse aggregatex specific gravity of fine aggregatesx1000
g mass of fine aggregates=ex volume of fine agregatesxspecific gravityof agregatesx1000
calculation of m35 grade concrete with fly ash
step 1 stipulation for concrete design mix
grade designation m35
type of cement opc43 gradeconfirming to is8112
type of mineral size of agregate flyash confirmingto is8112
maximum nominal size of agregate 20mm
minimum cement content 320kg/m3
maximum water cement ratio 0.45
workability 100mm
exposure condition serve
method of concrete placing pumping
degree of supervision good
type of agregate crushed angular aggregates
maximum cement content 450kg/m3
chemical admixture super pastisizer
step 2 test data for materials
cement used opc43 grade of cement
specific gravity of cemnt 31.5
flyash confirming to is8112
specific gravity of fly ash 2.2
chemical admixture sper pllassticizer confirmis9103
specific gravity of coarse aggregate 2.74
fine aggregate 2.74
water absorption of coarse aggregate 0.5%
water absorption of fine aggregate 1.0%
free surface moisture of coarse aggregate nil
fine aggregate nil
sieve analysis coarse aggregate confirming to table 2383
sieve analysis fine aggregates table 4 is 383
step 3 target strength for mix propotion
f'ck=fck =1.65s
35+1.65x5=43.25n/mm2
step4
selection of water cement ratio
grade concrete can be found in table5
w/c ratio 43.25n/mm2
adopted water cement ratio is 4.4
0.44<0.45
selection of water content
from table 2 of is 10262 2009
maximum water content of 20mm aggregate 186l
increase of 3%water 186+(6/100)x186=187l
for every extra slump contentfrom 50mm
slump. so a 6%to be added to it
197*0.8=158l
water requied 158l
calculation of cemnnt and fly ash requiedd
adopted w/c ratio 0.44
total cemnntation(cement+fly ash)requied=158/0.44=359kg/m3
final cemntatitios content 359x1.10=359kg
from table 5 is 456minium cemnt content 320kg
395>320kg/m3
cementanious material 395
fly ash content is taken as 30/of the cementatious cement 395x3=118.5kg/m3
cement quality saaveddue to fly ash addition 350-277=73kg/m3
volume of coarse aggregate and fine aggregate
in the presentcasse water-cement ratio is 0.44 volume of coarse aggregate is requiedd to the increased to decrease the fine aggregate content the propotion of volume of coarse aggregate is increased by 0.02 as the rateof 0.01/ for every 0.05in water cemnt ratio
correctedd volume of propotion 0.632
coarse aggregate for water cement ratio 0.632x0.9=0.568
volume of fine aggregate 1-0.568=0.431
mix calculation
volume of concrete 1m3
volume of cement 277/3.15x1/1000=0.08m3
volume of fly ash 118/2.2x1/1000=0.053
volume of water 158/1x1/1000=0.158m3
volume of chemical admixture 7.6/1.145x1/1000=0.006m3
volume of all aggregtae 1-0.087+0.053+0.158+0.006=0.696m3
mass of coarse aggregate=0.696x0.568x2.74x1000=1077kg/3
mass of fine aggregATe 0.696x0.431x2.74x1000=822kg/m3
mix propotion
cement 277kg/m3
fly ash 118
water 1581/m3
fine aggregate 822
coare aggregate 1077
chemical admixture 7.18kg/m3
water cemnt ratio 0.4
mix propotion inn weight 1:2.08:2.72
calculate the m50 grade concrete with ouutfly ash
step 1 stipulation for concrete mix design
garde designation m50
type of cemnt opc53grade confirming is bis 12269-1987
maximum nominal size of aggregate 20mm
maximum cemnt content 320kg/m3 table 5 is 456-2000
maximum water cement ratio 0.45
workability 100mm
expusore condition severe
method of concrete palcing pumping
degree of supervision good
tyype of aggregate crushed angular aggregate
max cemnt content 450kg/m3
chemical admixture super plastisizer
test data for materials
cemnt used opc 53grade confirming
cemnt gravity of cemnt 3.15
chemical admixture super plastisizer confirming to is9103
specific gravity of fine aggregate 2.74
specific gravitty of coarse aggregate 0.64
water absorption of coarse aggregate 0.5
fine aggregate 1.0/
free surface moisture of coarse aggregate nil
fine aggregate nil
sieve analysis of coarse aggregate is 383
sieve analysis of fine aggregate grading zone 2
target mean strength for mix propotion f'ck=fck+1.65s
50+1.65x5=58.25n/mm2
selection of water cemnt ratio m50
max water cemnt ratio=0.45
adopted water cemnnt ratio 0.44
0.44<0.45
sealctio of water content
max water content for 20mm aggregate 186l
3/wterofwater content for everry extra slump 25mm slump from 50mm
186+6/100x186=197l
based on tria;l supervision 197x0.8=158l
calculation of cement requied
adapted w/c ratio 0.44
cement content 158/0.44=359kg/m3
359>320kg/m3
volume of coarse aggregate and fine aggregate
from table 3 the volume of coarse aggregate 0.62
volume of fine aggregate 0.50
correctedd propotion of coarse aggregate 0.632
pumpable concrete 0.632x0.9=0.568
volume of fine aggregate 1-0.576=0.431
mix calculation
volume of concrete 1m3
volume of cement =0.41m3
volume of water =0.158m3
vlume of chemical admixture 7.6/1.145x1/1000=0.006m3
volume of all aggregates 0.722m3
mass of coarse aggregate 1123m3
mass of fine aggregate 821m3
mix propotion
cemnt 359kg/m3
water 158.1/m3
fine aggregate 821kg/m3
coase aggregate 1121kg/m3
chemical admixture 7.18kg/m3
water cemnt ratio 0.44
toatal mix propotion 1:2 28:3.12 result mix propotion of m50 grade 1:2.28:3.12