Project on Concrete Mix Design for various grades of Concrete
AIM:- Calculation of Concrete Mix Design for M35 grade concrete with fly ash
REQUIRED DATA:-
1.Grade of concrete-M35
2.Cement garade-opc 53grade
3.Maximum nominal size of aggregate- 20mm
4.Explore condition-Sever
5.Minimum cement content-340
6.Workability in terms of slump-75mm
8.Standard deviation-5.0 N/mm²
9.Type of coarse aggregate-Crushed angular aggregate
10.Water cement ratio-0.45
11.Fine aggregate-Zone-2
12.Tpe of minaral admixiture
TEST DATA OF MATERIAL:-
1.Specific gravity of cement-3.14
2.Specific gravity of fine aggregate-2.571
3.Specific gravity of coarse aggregate-2.799
4.Specific gravity of water-1.0
5.Admixture type-Superplasticizer
Step-1:-Target mean strength
| f'ck=fck+1.65 S |
f'ck=35+1.65X5=43.25
Step_2:-calculation of water cement ratio
Exposure condition- Sever
IS-456-2000,table-3,5 p.no,30
water cement ratio - 0.45
It can be reduce since we use admixture
w/c ratio=0.45-0.05=0.4
Water cement ratio =0.4
Step_3:- Water content
IS-10262-table,4-p.no.5
20mm aggregate-186kg(for 50mm slump)
75mm slump
For every 25mm-add 3%(IS-10262 -l.5.3)
186+3% of 186=191kg
For super plasticizer reduce 20%
191-(20%of191)=152.8
Water content=152.8kg
Step_4:-Calculation of cement content
Water cement ratio= Water content/Cement content
Cment content= Water content/ Water cement ratio
=152.8/0.4=382kg/m³>320kg/m³
Cement content =382 kg/m³
Step_5:- Aggregate proportion between CA and FA
IS-10262, table-5 p.no.6,cl.5.5.1
Zone-2-0.62(w/c-0.5)
Every 0.05 decrease and increase 0.01,(w/c-0.45)
(0.45-0.4=0.005)
0.62+0.01=0.63
For pumpable concrete CA can be reduce up to 10% (IS-10262,cl 5.5.2)
Volume of CA =0.63-(10%of0.63)=0.549
Volume of FA=1-0.549=0.451
Step_6:-Mix calculation
a)Volume of concrete-1m³
b)Volume of cement
(mass/sp,gravity)X(1/1000)
=382/3.14X1/1000=0.121m³
c)Volume of water
(mass/sp,gravity)X(1/1000)
=152.8/1X(1/1000)=0.152m³
d)Volume of admixture
(mass/sp,gravity)X(1/1000)
mass - 1.1 of cement
1.1(100)X382/(1.12X1000)=0.0375m³
(1.12 sp.gravity of admixture is assumed)
e) Volume of all in aggregate
1-(b+c+d)
1-(0.121+0.152+0.0375)=0.689
f)Mass of coarse aggregate
Volume of all in aggregate X volume of coarse aggregate X specific gravity of coarse aggregate X 1000
0.689 X 0.549 X 2.799 X 1000=1058kg
g) Mass of fine aggregate
Volume of all in aggregate X volume of fine aggregate X specific gravity of fine aggregate X 1000
0.689 X 0.451 X 2.571 X 1000 =798kg
SUMMARY
CEMENT-382 KG/m³
WATER- 152 KG/m³
FINE AGGREGATE- 798 KG/m³
COARSE AGGREGATE- 1058 KG/m³
ADMIXTURE- 4,202 KG/m³
WATER CEMENT RATIO- 0.4