Project on Concrete Mix Design for various grades of Concrete
Concrete mix design for M35 garde concrete with fly ash:
i) Stipulations for proportioning of M35 grade concrete-
a)Grade of designation - M35
b)Type of cement - OPC 53
c)Type of admixture - fly ash
d)Maximum nominal size of aggregate - 20mm
e)Minimum cement content - 340 Kg(table 5-IS456)
f)Maximum cement content -450(as per code)
g)PArtial replacement of cement by fly ash - 30% (as per requirement)
h)maximum W/C ratio - 0.45(table 5 -IS456)
i)Workability - 100mm
j)Chemical admixuture - PCS type
ii)Test data for materials -
a)Cement used - OPC 53 -confirming to IS 8112
b)Specific gravity of cement - 3.15 - test - IS 2720
c)MIneral admixture - fly ash- confirming to IS2089
d) Specific gravity of fly ash -2.90
e)Chemical admixture - @0.6% - IS9103
f)Specific gravity of -test-IS2386
coarse aggregate - 2.74
fine aggregate -2.74
admixture PCE based-1.12
g)Water absorption -Test-IS2386
coarse aggregate - 0.5%
fine aggregate -1%
h)seive analysis - test-IS2386
coarse aggregate - confirming to table 2 -IS383
fine aggregate -zone II-confirming to table 4- IS383
iii)Target strength for mix proportions of M35 grade concrete:
Fck = fck+1.65s("s" from table 1 -IS 10262)
Fck= 35+1.65*5=43.25N/mm2
iv)Selection of water-cement ratio:
maximum W/C ratio=0.45 (table 5-IS 456)
adopted W/C ratio =0.45
v)Selection of water content:
maximum water content =186L(table 2 -IS1026)
water content for 100mm slump =186+(0.06*186)=197.16L
percentage of reduction in water content =20%
water content requirement after Sp =198-(0.20*198)=157.73
adopted water content =160L
vi)Calculation fo cement and fly ash content:
adopted water cement ratio=0.45
total cemetitious requirement = water content/water cement ratio=160/0.45=355.55Kg
final cementitious content = 356*1.10 =391.6Kg
minimum cement content required for "severe" exposure = 340Kg- table 5-IS456
adopted cementitious content = 391.6Kg>340Kg
fly ash content requirement=391.6*0.30(30% replacement)
= 117.48-118kg
cement content requirement = cementitous content - flyash= 391.6-117.48=274.12
calculation of super [email protected]% to the mass of cementitious content = 391.6*(06/100)=2.35kg
vii)Coarse aggregate and fine aggregate:
coarse aggregate ratio = 0.62 -table 3 -IS10262(for W/C = 0.5)
coarse aggregate ratio for 0.45 w/c/=0.63 adding 0.01 for every decresases0.05 and vice versa
final fine aggregate ratio = (1-0.63)=0.37
viii)Mix calculation of M35 garde concrete:
a)volume of concret =1cu.m
b)total volume of cement = cement/(s.g*1000)=275/(3.15*1000)=0.087cu.m
c)total volume of fly ash =flyash/(s.g*1000)= 118/(2.5*1000)=0.041cu.m
d)volume of water = water /(s.g*1000)=160/(1*1000)=0.016cu.m
e)volume of superplasicizers= superplasticizer/(s.g*1000)=2.35/(1.12*1000)=0.002cu.m
f)total aggregate required = a-(b+c+d+e)=1-(0.087+0.041+0.16+0.002)=0.71cu.m
g)coarse aggregate (c.a) =f*c.a ratio*s.g*1000=0.71*0.63*2.74*1000=719.8kg
h)fine aggregate(f.a)=f*f.a ratio*s.g*1000 = 0.71*0.37*2.74*1000=719.8kg
CEMENT FLYASH SAND AGGREGATE WATER AND SUPERLASICIZER NEEDE FOR M35 GRADE CONCRETE:
1.Cement-275kg
2.Flyash-118kg
3.Fine aggregate-720kg
4.Coarse aggregate-1226kg
5. Water -160L
6. PCE based supeplasicizer-2L
to find the design mix ratio divide the calculated value of all materials by the weigth of cement.There for mix ratio of M35 garde concrete by weigth is = cement :flyash:F:A:C.A:WATER=1:0.4:2.6:4.46:0.58