Project on Concrete Mix Design for various grades of Concrete
Calculate the Concrete Mix Design for M35 grade concrete with fly ash & M50 grade concrete without Fly ash
Calculate the Concrete Mix Design for M35 grade concrete with fly ash
AIM: To calculate the concrete mix design for M35 grade concrete with flyash
Code i used : IS 10262:2009
IS 10262:1982
IS 456:2000
IS 383:1970
Assume some data for proportioning the M35 grade concrete with flyash
Grade designation:M35
Type of cement: OPC 43grade
Type of mineral admixture:Flyash
Maximum nominal size of aggregate:20mm
Exposure condition: very severe (for reinforced concrete)
minimum cement content: 340kg/m3
maximum water cement ratio : 0.45
Degree of supervision: Good
workability :75 mm (slump)
Method of concrete placing: pumping
Type of aggregate: crushed angular aggregate.
maximum cement content (OPC) : 450 kg/m3
chemical admixture type: superplasticizer
specific gravity of cement:3.15
specific gravity of flyash:2.4
specific gravity of coarse aggregate: 2.74
specific gravity of fine aggregate:2.74
water absorption of coarse aggregate :0.5%
water absorption of fine aggregate: 1%
free moisture of coarse aggregate :nill
free moisture of fine aggreagte :nill
fine aggregate: conforming to grading zon I
STEP BY STEP PROCEDURE
1.Find out the target mean strength. (IS 10262:2009 clause 3.2 & table 1)
Target mean strength (f'ck)=fck+1.65*s
f'ck=35+1.65*5
f'ck =43.25 N/mm2
2.selection of water cement ratio.
They are three ways
(i) correlation between free water-cement ratio and compressive strength of concrete. w/c=0.36 (IS 10262:1982 fig 1)
(ii) correlation between free water-cement ratio and concrete strength for different cemet strengths. w/c=0.34 (IS 10262:1982 fig 2)
(iii) maximum water-cement ratio for different exposures with normal weight aggregate f20mm nominal maximum size. w/c =0.45 (IS 456:2000 table 5)
so I adopt water-cement ratio is 0.40
3. Selection of water content.
maximum water content for 20mm aggregate =186 litres (IS 10262:2009 clause 4.2 and table 2)
Estimated water content for 75 mm slump =186+(3/100)*186
=197 litre
Assume 25% water reduction takes place while using super plasticizer.
Arrived water content = 197*0.75
=148 litre
4. calculation of cement and flyash content.
water-cement ratio= 0.40
w/c=0.40
c=148/0.40
c=370 kg/m3
:.370>340kg/m3 hence, ok.
Increase 10% cementitious matertial content while removing cement replacing with other.
cementitious material content = 370*1.10
=407 kg/m3
water-cement ratio=148/407
=0.363
Fly ash @25% of total cementitious material content = 407*0.25
=102 kg/m3
cement content=407-102
=305 kg/m3
saving of cement content while using flyash=370-305
=65kg/m3
2% by mass of the admixture( super plasticizer) to the cement=370*0.02
=7.4 kg/m3
5. proportion of volume of coarse aggregate and fine aggregate content (IS 383:2007)
volume of coarse aggregate to 20mm size aggregate and fine aggregate (zone 1) for water cement ratio of 0.50=0.60
The corrected proportion of volume of coarse aggregate for the water cement ratio of 0.40=0.62
For pumpable concrete these values should be reduced by 10%
volume of coarse aggregate=0.62*0.9
=0.56 (IS 10262:2009 table 3 and clause 4.4)
volume of fine aggregate =1-0.56
=0.44
6. mix calculation
(a)volume of concrete =1m3
(b)volume of cement = (mass of cement/specific gravity of cement)*(1/1000)
=(305/3.15)*(1/1000)
=0.096 m3
(c)volume of flyash =(mass of flyash/specific gravity of flyash)*(1/1000)
= (102/2.4)*(1/1000) (IS 10262:2009 clause 4.6)
=0.042 m3
(d)volume of water=(148/1)*(1/1000)
=0.148m3
(e) volume of admixture=(7.4/1.145)*(1/1000)
=0.006 kg/m3
(f) total volume of aggragate=a-(b+c+d+e)
=1-(0.096+0.042+0.006+0.148)
=0.708 m3
(g) mass of coarse aggregate =0.708*2.74*1000*0.56
=1086
(h) mass of fine aggregate =0.708*2.74*1000*0.44
=854 kg
7. Mix proportion
cement =305 kg/m3
fly ash=102 kg/m3
water content=148 kg/m3
fine aggregate=854 kg/m3
coarse aggregate =1086kg/m3
Admixture (super plasticizer)= 7.4kg/m3
water cement ratio=0.363
RESULT : The concrete mix design for M35 grade concrete with flyash = 148:407:854:1086
= 0.36:1:2:2.7
Calculate the Concrete Mix Design for M50 grade concrete withuot fly ash
AIM: To calculate the concrete mix design for M50 grade concrete with out flyash
Code i used : IS 10262:2009
IS 10262:1982
IS 456:2000
IS 383:1970
Assume some data for proportioning the M50 grade concrete without flyash
Grade designation:M50
Type of cement: OPC 43grade
Maximum nominal size of aggregate:20mm
Exposure condition: very severe (for reinforced concrete)
minimum cement content: 340kg/m3
maximum water cement ratio : 0.45
Degree of supervision: Good
workability :75 mm (slump)
Method of concrete placing: pumping
Type of aggregate: crushed angular aggregate.
maximum cement content (OPC) : 450 kg/m3
chemical admixture type: superplasticizer
specific gravity of cement:3.15
specific gravity of coarse aggregate: 2.74
specific gravity of fine aggregate:2.74
water absorption of coarse aggregate :0.5%
water absorption of fine aggregate: 1%
free moisture of coarse aggregate :nill
free moisture of fine aggreagte :nill
fine aggregate: conforming to grading zon I
STEP BY STEP PROCEDURE
1.Find out the target mean strength. (IS 10262:2009 clause 3.2 & table 1)
Target mean strength (f'ck)=fck+1.65*s
f'ck=50+1.65*5
f'ck =58.25 N/mm2
2.selection of water cement ratio.
They are three ways
(i) correlation between free water-cement ratio and compressive strength of concrete. w/c=0.30 (IS 10262:1982 fig 1)
(ii) correlation between free water-cement ratio and concrete strength for different cemet strengths. w/c=0.34 (IS 10262:1982 fig 2)
(iii) maximum water-cement ratio for different exposures with normal weight aggregate f20mm nominal maximum size. w/c =0.45 (IS 456:2000 table 5)
so I adopt water-cement ratio is 0.35
3. Selection of water content.
maximum water content for 20mm aggregate =186 litres (IS 10262:2009 clause 4.2 and table 2)
Estimated water content for 75 mm slump =186+(3/100)*186
=197 litre
Assume 25% water reduction takes place while using super plasticizer.
Arrived water content = 197*0.75
=148 litre
4. calculation of cement and flyash content.
water-cement ratio= 0.35
w/c=0.35
c=148/0.35
c=423 kg/m3
:.423>340kg/m3 hence, ok.
2% by mass of the admixture( super plasticizer) to the cement=423*0.02
=8.46 kg/m3
5. proportion of volume of coarse aggregate and fine aggregate content (IS 383:2007)
volume of coarse aggregate to 20mm size aggregate and fine aggregate (zone 1) for water cement ratio of 0.50=0.60
The corrected proportion of volume of coarse aggregate for the water cement ratio of 0.40=0.62
For pumpable concrete these values should be reduced by 10%
volume of coarse aggregate=0.62*0.9
=0.56 (IS 10262:2009 table 3 and clause 4.4)
volume of fine aggregate =1-0.56
=0.44
6. mix calculation
(a)volume of concrete =1m3
(b)volume of cement = (mass of cement/specific gravity of cement)*(1/1000)
=(423/3.15)*(1/1000)
=0.134 m3
(c)volume of water=(148/1)*(1/1000)
=0.148m3 (IS 10262:2009 clause 4.6)
(d) volume of admixture=(8.46/1.145)*(1/1000)
=0.005 kg/m3
(f) total volume of aggragate=a-(b+c+d)
=1-(0.134+0.005+0.148)
=0.713 m3
(g) mass of coarse aggregate =0.713*2.74*1000*0.56
=1094 kg
(h) mass of fine aggregate =0.713*2.74*1000*0.44
=859 kg
7. Mix proportion
cement =423 kg/m3
water content=148 kg/m3
fine aggregate=859 kg/m3
coarse aggregate =1094kg/m3
Admixture (super plasticizer)= 8.46kg/m3
water cement ratio=0.35
RESULT : The concrete mix design for M50 grade concrete with out flyash = 148:423:859:1094
=0.35:1:2:2.6