Project on Concrete Mix Design for various grades of Concrete
The Concrete Mix Design for M35 grade concrete with fly ash
- Grade Designation M35
- Type of cement OPC 53
- Type of admixture fly ash
- Maximum nominal size of aggregate 20mm
- Minimum cement content 340 kg (as per IS456 table 5)
- Maximum cement content 450kg (as per IS 456)
- Maximum water cement ratio 0.45(IS 456 :2000 table 5 exposure condition)
- Workability 100mm
- Chemical admixture Superplasticizer conforming to IS 9103
- Type of agrregate : angular crushed aggregate
- Degree of supervision : Good
Test data for material
- Cement used : OPC 53 grade conforming to IS 8112
- Specific gravity 3.15
- Chemical admixture Superplasticizer conforming to IS 9103
- Specific gravity of
- Coarse aggregate :2.74
- Fine agregate 2.74
e. Water absorption:
- Coarse aggregate :0.5%
- Fine agregate 1.0%
f. Sieve Analysis:
- Conforming ti IS 383 table 2
- Fine aggregate zone 2 conforming to IS 383 table 4
g. Target Strength for mix proportioning:
f'ck=fck+1.65*S
f'ck= 35 + 1.65* 5 ( S=5 from table 1 IS10262)
f'ck=43.25N/mm^2
h. Selection of water cement ratio
maximum w/c ratio = 0.45 (IS456 table 5)
adopted w/c ratio = 0.45
i. Selection of water content
Maximum water content =186 L (IS 10262 table 2)
Water content for 100mm slump = 186+(.06*186)
= 197.16
Since superplastizers are used water content reduced by 20 %
therefore water adopted = 157.73 = 160 L
j. Caculation of fly ash and cement
Adopted water cement ratio = 0.45
total cementious required ( cement + fly ash)= water content/water cement ratio
= 160/0.45 = 355.55 Kg
Since fly ash is used increase cementious content by 1.1% i.e = 356*1.1 = 391.6 kg
from IS456 table 5 minimum cement content required for severe exposure is 340kg
therefore 340kg<391.6kg
adopted 391.6 kg cementious content
Fly ash content required = 391.6 * 30% (30% replacement )
= 117.48 i.e 118 kg
Cement content required = cementious content - fly ash
= 391.6-117.48
=274.12 kg
Calculation of superplastisizer at 0.6% i.e 391.6*0.6/100 = 2.35 kg
K. Coarse and fine aggregate
coarse aggregate ratio =0.62 (for W/C 0.5 table 3 IS 10262)
coarse aggregate ratio for 0.45 W/C =0.63 (adding 0.01every decrese 0.05)
final fine aggregate ratio = 1 - 0.63 = 0.37
MIX CALCULATION OF M35 GRADE CONCRETE
- volume of concrete = 1 m^3
- total volume of cement = cement content / specific gravity * 1000
=275/(3.15*1000)
=0.087 cu.m
C.total volume of fly ash = fly ash content / specific gravity * 1000
=118/(2.5*1000)
=0.041 cu.m
D. volume of water = water content / specific gravity * 1000
= 160/(1*1000)
=0.160 cu.m
E.volume of superplasticizer = superplasticizer content / specific gravity * 1000
= 2.35 /(1.12 *1000)
=.002 cu.m
F.Total aggregate required = A-(B+C+D+E)
= 1- (.087 + .041 + 0.16 + .002)
=0.71 cu.m
G. Coarse Aggregate = F * C.A ratio* specific gravity*1000
= 0.71 * 0.63 *2.74 *1000
= 1225.6 kg
H. Fine Aggregate = F * F.A ratio* specific gravity*1000
= 0.71*0.37*2.74*1000
= 719.8 kg
Therefore Cement = 275kg
Fly ash = 118 kg
Fine aggregate = 720kg
Coarse aggregate = 1226 kg
water = 160L
Superplastisizer = 2L
to find M35 design mix ratio divide calculated value of material by weight of cement
cement :Flyash:F.A : C.A : water
1 : 4.2: 2.6 :4.46 : 0.58