Project on Concrete Mix Design for various grades of Concrete
Calculation of concrete mix design for M35 grade concrete with fly ash
Aim - The main aim of this is to calculate the concrete mix design for M35 containing fly ash
Introduction - We calculate mix design because of production of concrete should have good properties and economical with desired strength according to construction
Procedure-
1
a)Cement used - OPC 43 grade
b) Specefic gravity of cement - 3.15
c) Type of admixture - fly ash and super plasticizers
d) Specefic gravity of coarse aggregate and fine aggregate - 2.74
e) Water absorption - coarse aggregate - 0.5% , fine aggregate - 0%
f) Seive analysis - according to amount is retaining of aggregate from table 2 IS383 zone
2) Target strength
Target strength of mix proportions
f'ck = fck+1.65S (S from table 1 IS10262 : 2009)
35+1.65*5
=43.25
3) Water cement ratio
Selection of water cement ratio for severe condition from table 5
maximum water cement ratio = 0.45
But adopted as 0.40 based on experiences
4) Water content
From table 2 of IS10262 2009 is 186 lit till 50mm slump
add 3% for every 25mm so add 6 %
186+11 = 196
Here super plastisizers are added so reduce water to 20% 196-20@ = 140litres
5) Cement content
Water cement ratio = 0.4
Cement content = 140/0.4 = 350kg/m3
Percentage of fly ash decided by requirments
Increase cementaneous material to 10% for strength 350+10% = 385kg/m3
Water content is 140kg/m3
Water cement ratio is 140/385 = 0.364
Add fly ash of 30% to total cementaneous material 385x30% = 115kg/m3
Deduct 115kg/m3 in total cemenaneous 385-115 = 270kg/m3
Total cement used = 270kg/m3
Fly ash used = 115kg/m3
6) Proportioning of volume of coarse and fine aggregete
Volume of coarse aggregate for 20mm size aggregate (zone1 based on seive analysis IS383)
we get 0.6 for water cement ratio which is more so proportion of coarse aggregate is increased to 0.02
for every 0.05 increase 0.01
=0.6+0.02
vol of coarse aggregate = 0.62
Volueme is reduced to 10% for pumpable concrete
Volume of coarse aggregate = 0.56
Volume of fine aggregete = 1-0.56 = 0.44
7)Mix calculations
a) Volume of concrete = 1m3
b) Volume of cement = (mass of cement)/(specefic gravity)x (1/1000)
(270/3.15)x(1/1000) = 0.086m3
c) Volume of fly ash = (115/2.2)x(1/1000)= 0.052m3
d) Volume of water = (140/1)x(1/1000) = 0.140m3
e) Chemical admixtures = (7.6/1.145)x(1/1000) = 0.006m3
f) Volume of coarse and fine aggregate = total volume - all contents
1-(0.086+0.052+0.140+0.006)
= 0.723m3
g) Mass of coarse aggregate = total vol x vol of coarse aggregete x specefic gravity x 1000
= 0.723x0.44x2.74x1000 = 1098kg/m3
h) Mass of fine aggregete = 0.723x0.44x2.74x1000= 863kg/m3
i) Mass of fly ash = 0.723 x 0.052 x 2.2 x 1000 = 115 kg/m3
Results-
Total cement - 350kg/m3
Water content - 140kg/m3
Fine aggregate - 863kg/m3
Coarse aggregate - 1140kg/m3
Fly ash - 115 kg/m3
Aim - The main aim of this is to calculate the concrete mix design for M50 without containing fly ash
Introduction - We calculate mix design because of production of concrete should have good properties and economical with desired strength according to construction
Procedure-
1
a)Cement used - OPC 43 grade
b) Specefic gravity of cement - 3.15
c) Type of admixture - super plasticizers
d) Specefic gravity of coarse aggregate and fine aggregate - 2.74
e) Water absorption - coarse aggregate - 0.5% , fine aggregate - 1%
f) Seive analysis - according to amount is retaining of aggregate from table 2 IS383 zone
2) Target strength
Target strength of mix proportions
f'ck = fck+1.65S (S from table 1 IS10262 : 2009)
50+1.65*5
=58.25
3) Water cement ratio
Selection of water cement ratio for severe condition from table 5
maximum water cement ratio = 0.28
But adopted as 0.30 on experiences
4) Water content
From table 2 of IS10262 2009 is 186 lit till 50mm slump
add 3% for every 25mm so add 6 %
186+11 = 196
Here super plastisizers are added so reduce water to 20% 196-20@ = 140litres
5) Cement content
Water cement ratio = 0.4
Cement content = 140/0.3 = 460kg/m3
Water content is 140kg/m3
Water cement ratio is 140/460 = 0.304
6) Proportioning of volume of coarse and fine aggregete
Volume of coarse aggregate for 20mm size aggregate (zone1 based on seive analysis IS383)
we get 0.6 for water cement ratio which is more so proportion of coarse aggregate is increased to 0.02
for every 0.05 increase 0.01
=0.6+0.02
vol of coarse aggregate = 0.62
Volume is reduced to 10% for pumpable concrete
Volume of coarse aggregate = 0.56
Volume of fine aggregete = 1-0.56 = 0.44
7)Mix calculations
a) Volume of concrete = 1m3
b) Volume of cement = (mass of cement)/(specefic gravity)x (1/1000)
(270/3.15)x(1/1000) = 0.0622m3
c) Volume of water = (140/1)x(1/1000) = 0.140m3
e) Chemical admixtures = (7.6/1.145)x(1/1000) = 0.006m3
f) Volume of coarse and fine aggregate = total volume - all contents
1-(0.0622+0.052+0.140+0.006)
= 0.748m3
g) Mass of coarse aggregate = total vol x vol of coarse aggregete x specefic gravity x 1000
= 0.748x0.56x2.74x1000 = 1147kg/m3
h) Mass of fine aggregete = 0.745x0.44x2.74x1000= 902kg/m3
Results-
Total cement - 460kg/m3
Water content - 140kg/m3
Fine aggregate - 902kg/m3
Coarse aggregate - 1147kg/m3