Project on Concrete Mix Design for various grades of Concrete
M50 grade concrete without Fly ash :
AIM:
To design the M50 grade of concrete without fly ash
INTRODUCTION:
It is a systematic and scentific choosing economical relative proportion of various ingradients.
compression strength may depends upon the quality,quantity of concrete it is also depends on mixing,batching,placing,compactiong and curing.
cost of concrete depends upon material cost,and labour.
GOOD CONCRETE CHARACTERISTIC:
It should attend the require strength fullfull the durability requrments:
DESIGN OF M50 GRADE CONCRETE:
a) grade of concrete : M50
b) type of cement : OPC 43 grade conforming to IS 8112
c) maximum nominal size of the
aggregate : 20 mm
d) exposure condition : severe
e) workability : 75 mm (slump)
f) method of concrete placing : pumping
g) degree of site control : good
h) type of aggregate : crushed angular aggregates
i) maximum cement content : 450 kg/m^3
j) chemical admixtures type : superplasticizer normal
TEST DATA FOR MATERIAL :
a) cement used : OPC 43 grade conforming to IS 8112
b) specific gravity of cement : 3.15
c) chemical admixture : superplasticizer
d)
1)specific gravity of coarse aggregate : 2.74
2) specific gravity of fine aggregate : 2.65
3) specific gravity of chemical admixture : 1.145
e) water absorption
for coarse aggregate : 0.5 %
for fine aggregate : 1 %
f) moisture content of aggregate
for coarse aggregate : nil
for coarse aggregate : nil
STEP - 1 TARGET MEAN STRENGTH FOR MIX PROPORTINING :
F'ck = Fck + 1.65*S
From table 1 IS 10262 - 2019 (S = 5)
F'ck = 50 + 1.65*5
= 58.25 N/mm^2
STEP - 2 SELECTION OF WATER CEMENT RATIO
From GRAPH IS 10262 - 2019
The water cement ratio is 0.32
From IS 456 - 2000 the maximum water cement ratio for severe condition is 0.45
hence take the least value .
STEP - 3 CALCULATION OF WATER CONTENT:
From table 4 IS 10262 - 2019
the water content for 20mm aggregate with slump of (25 - 50) is 186 litres
for futher increase or decrease of 25 mm slump increase or decrease 3% of water content
the water content = 186+(3*186/100)
= 191.58 kg
the test results shows that using the plasticizer can reduce the water cement ratio by 29%
so, the water content is = 191.58*0.71
= 136.02 kg
assume 136 kg
STEP - 4 CALCULATION OF CEMENT CONTENT:
W/C = 0.32
136/0.32 = C
cement content = 425 kg the maximum content is 450
hence ok.
STEP -5 proportining the volumne of coarse and fine aggregate
From table 5: IS 10262 - 2019
volumne of coarse aggregate corresponding to 20mm size zone is 0.60
for the pumpaple concrete these values reduced by 10%
therefore the volumne of coarse aggregate is = 0.62*0.9
= 0.56
volumne of fine aggregate = 1 - 0.56
= 0.44
a) volumne of concrete = 1m^3
b) volumne of cement = (mass of cement / specific gravity of cement)*(1/1000)
= (425/3.15)*(1/1000)
= 0.134 m^3
c) volumne of water = (mass of water / specific gravity of water)*(1/1000)
= (136/1)*(1/1000)
= 0.136 m^3
d) volumne of chemical admixture
add 1% to cementinious material = (mass of chemical admixtures/specific gravity of admixture)*(1/1000)
=( 4.25/1.145)*(1/1000)
= 0.0037 m^3
e) volumne of coarse and fine aggregate = [a - (b+c+d)]
= [ 1- ( 0.134+0.136+0.0037)]
= 0.72
f) mass of the coarse aggregate = e* volumne of coarse aggregate*specific gravity CA*1000
= 0.72*0.56*2.74*1000
= 1104.768 kg/m^3
= 1104 kg/m^3
g) mass of the fine aggregate = e* volumne of fine aggregate*specific gravity of FA*1000
= 0.72*0.44*2.65*1000
= 839.52kg/m^3
= 839 kg/m^3
MIX PROPORTIONING :
cement : 425 kg/m^3
water : 136 kg/m^3
fine aggregate : 839 kg/m^3
coarse aggregate : 1104 kg/m^3
chemical addmixture : 4.25 kg/m^3
W/C ratio : 0.32 kg/m^3
The proportion is (Cement:coarse aggregate: fine aggregate) = (1:2.5:1.97)
DESIGN OF M35 GRADE OF CONCRETE:
Mix prportining of concrete using fly ash as part of replacement of OPC
a) grade of concrete : M35
b) type of cement : OPC 43 grade conforming to IS 8112
c) type of mineral admixture : fly ash conforming to IS 3812(part-1)
d) maximum nominal size of the
aggregate : 20 mm
e) exposure condition : severe
f) workability : 100 mm (slump)
g) method of concrete placing : pumping
h) degree of site control : good
i) type of aggregate : crushed angular aggregates
j) maximum cement content : 450 kg/m^3
k) exposure condition : severe
l) chemical admixture type : superplasticizer
TEST DATA FOR MATERIAL :
a) cement used : OPC 43 grade conforming to IS 8112
b) specific gravity of cement : 3.15
c) fly ash : conforming to IS 8112
d) specific gravity od fly ash : 2.2
e) chemical admixture : superplasticizer
f)
1)specific gravity of coarse aggregate : 2.74
2) specific gravity of fine aggregate : 2.74
3) specific gravity of chemical admixture : 1.145
g) water absorption
for coarse aggregate : 0.5 %
for fine aggregate : 1 %
h) moisture content of aggregate
for coarse aggregate : nil
for fine aggregate : nil
STEP - 1 TARGET MEAN STRENGTH FOR MIX PROPORTINING :
F'ck = Fck + 1.65*S
From table 1 IS 10262 - 2019 (S = 5)
F'ck = 35 + 1.65*5
= 43.25 N/mm^2
STEP - 2 SELECTION OF WATER CEMENT RATIO
From GRAPH IS 10262 - 2019
The water cement ratio is 0.39 based on the experience assume 0.4
From IS 456 - 2000 the maximum water cement ratio for severe condition is 0.45
hence take the least value .
STEP - 3 CALCULATION OF WATER CONTENT:
From table 4 IS 10262 - 2019
the water content for 20mm aggregate with slump of (25 - 50) is 186 litres
for futher increase or decrease of 25 mm slump increase or decrease 3% of water content
the water content = 186+(6*186/100)
= 197 kg
the test results shows that using the plasticizer can reduce the water cement ratio by 29%
so, the water content is = 197*0.71
= 140 kg .
STEP - 4 CALCULATION OF CEMENT CONTENT:
water/cement ratio = 0.4
cementitous material ( cement +fly ash )content = 140/0.4
= 350 kg/m^3
from table of IS 456 minimum cement content for "severe" exposure condition = 340 kg/m^3
the percentage of fly ash is decided by the needs and quality of the material,here it is increased by 10 % cementitious material cocntent
cementitious material content = 350*1.10
= 385 kg/m^3
water content = 140 kg/m^3
so W/c ratio is = 140/385
= 0.364
fly ash @ 30% total cementitious material content = 385*(30/100)
= 115 kg/m^3
cement (OPC) = 385 - 115
= 270kg/m^3
saving of cement while using fly ash = 350 - 270
= 80 kg/m^3
fly ash being utilized = 115 kg/m^3
STEP -5 proportining the volumne of coarse and fine aggregate
From table 5: IS 10262 - 2019
volumne of coarse aggregate corresponding to 20mm size zone is 0.60
for the pumpaple concrete these values reduced by 10%
therefore the volumne of coarse aggregate is = 0.62*0.9
= 0.56
volumne of fine aggregate = 1 - 0.56
= 0.44
a) volumne of concrete = 1m^3
b) volumne of cement = (mass of cement / specific gravity of cement)*(1/1000)
= (270/3.15)*(1/1000)
= 0.086 m^3
c) volumne of the fly ash = (mass of fly ash / specific gravity of fly ash)*(1/1000)
= (115/2.2)*(1/1000)
=0.052 m^3
d) volumne of water = (mass of water / specific gravity of water)*(1/1000)
= (140/1)*(1/1000)
= 0.140 m^3
e) volumne of chemical admixture
add 1% to cementinious material = (mass of chemical admixtures/specific gravity of admixture)*(1/1000)
=( 4.25/1.145)*(1/1000)
= 0.0037 m^3
f) volumne of coarse and fine aggregate = [a - (b+c+d+e)]
= [ 1- ( 0.086+0.052+0.140+0.0037)]
= 0.71
g) mass of the coarse aggregate = f* volumne of coarse aggregate*specific gravity CA*1000
= 0.71*0.56*2.74*1000
= 1089.424 kg/m^3
= 1089 kg/m^3
h) mass of the fine aggregate = f* volumne of fine aggregate*specific gravity of FA*1000
= 0.71*0.44*2.74*1000
= 855.97 kg/m^3
= 855 kg/m^3
MIX PROPORTIONING :
cement : 270kg/m^3
water : 140 kg/m^3
fly ash : 115 kg/m^3
fine aggregate : 855 kg/m^3
coarse aggregate : 1089 kg/m^3
chemical addmixture : 4.25 kg/m^3
W/C ratio : 0.32 kg/m^3
The proportion is (Cement:coarse aggregate: fine aggregate) = (1:2.2:2.82)