Project on Concrete Mix Design for various grades of Concrete
(ANS 1= Mix design for m35 grade concrete with fly ash
PROCEDURE
STEP 1 Stipulation for proportioning
A grade designation : M35
B Type of cement : OPC 43 grade conforming to IS 8112
C Type of mineral admixture : fly ash confirming to IS3182
D Max nominal size of aggregate :20mm
E Min cement content :320
F Max water cement ratio : 0.45
G Workability : 100mm slump value of pumpable concrete
STEP 2 Test data for materials
A cement used : OPC 43 grade confirming to IS 8112
B Specific gravity of cement : 3.15
C Specific gravity to fly ash
D Water absorbtion : Coarse agg :0.5% Fine agg :1%
IS Seive size (mm) Analysis of coarse agg fraction % of different fraction combined
i ii i ii
20 100 100 60 40 100
10 0 71.2 0 28.5 28.5
4.75 9.4 3.7 3.7
2.36 0
STEP 3 To find target mean strength for mix proportioning
Target mean stength f'ck=FCK+1.65 =35 + 1.65 = 43.25 N/mm2
STEP 4 Max water cement ratio
is taken as = 0.45
STEP 5 Calculation of water content
Max water content for 20mm agg = 186 litre
for 100 mm slump = 186+ (6/100)*186=197 litre
as superplaticizer is used the water content is reduce upto 30%
STEP 6 Calculation of cement content
Water- cement ratio =0.4
cementatious material ( cement +fly ash)= 140/0.4 = 350 kg /m3
cement content for sever exposure =320kg/m3
STEP 7 Proportion of volume of coarse agg and fine agg
vol of coarse agg= 0.64*0.9= 0.576
vol of fine agg = 1-0.576=0.424
STEP 8 Mix calculation
mix calculatio per unit volume of concrete are
A volume of concrete = 1m3
B Volume of cement= ( mass of cement / specific gravity of cement ) 1/1000 = (270/3.15)*1/1000 = 0.086 m3
C vol of flyash = ( mass of fly ash / specific gravity of fly ash) *1/1000 = (115/2.2)*1/1000 = 0.052m3
D vol of water = ( mass of water/ speific gravity of water)*1/1000 = (140/1)*1/1000 = 0.140m3
E vol of chemical admixture = (7.6/1.14)*1/1000 = 0.006m3
STEP 9 Mix proportion
Cement = 270kg/m3
fly ash = 115 kg/m3
Water = 140 kg /m3
Water cement ratio = 0.364
RESULT : The mix design for M35 grade of concrete with fly ash is 1:2.15:2.94
MIX DESIGN OF M 50 GRADE CONCRETE
STEP 1 STIPULATION FOR PROPORTIONING
A Grade designation : M50
B Type of cement : OPC grade 43 conforming to IS 8112
C Maximum nominal size of aggregate : 20mm
D Min cement content : 320 kg/m3
E Max water cement ratio : 0.45
F Method of concrete placing :pumping
G Type of agg : crushed angular agg
STEP 2 TEST DATA FOR MATERIALS
A cement used : OPC 43 grade confirming to IS 8112
B Specific gravity of cement : 3.15
C Water absorbtion : Coarse agg :o.5% Fine agg :1%
STEP 3 SELECTION OF WATER CEMENT RATIO
From table : OF IS 456-2000 by ,exosure condition
water cement ratio = 0.45
STEP 4 TO FIND TARGET MEAN STRENGTH FOR PROPORTIONING
Target mean strength , f'ck =FCK + 1.65 s
50 +1.65 * 5 = 58.25
STEP 5 SELECTION OF WATER CONTENT
FOr 100mm slump = 186+(6/100)*186= 197 litre
STEP 6 CALCULATION OF CEMENT CONTENT
water cement ratio = 0.4
cement content = 140 /0.4 = 350 kg/m3
STEP 7 MIX CALCULATION
A volume of concrete = 1m3
B vol of cement = (350/3.15)*1/1000=0.111m3
C vol of chemical admixture = (7.6/1.145)*1/1000=0.006M3
STEP 8 MIX PROPORTION
Cement = 350 kg/m3
water = 140 kg/m3
fine agg = 863 kg/m3
coarse agg = 1173 kg/m3
RESULT 1:2.46:3.35