Project on Concrete Mix Design for various grades of Concrete
1 .m35 grade concrete mix design with fly ash
aim
mix design for m35 concrete design with fly ash
step 1
type of mix=design mix
grade designation=m35
type of cement=opc 43 (is1812-1989)
max nominal size of agg=20mm
minimum cement content=320kg/m3(is456,table-5)
max w/c ratio=0.45 asper table 5 is456
workability=125mm slump
exposure=severe
method of concrete=pumping
degree of supervision=good
agg type=angular
superplaticizer used
maximum cement content=450kg/m3
sp.gravity of cement=3.15
sp.gravity of CA=2.74
sp.G of FA=2.74
Sp.G of flyash= 2.2 (is3812 part1)
water absorbtion CA=0.5%
surface moisture FA=1%
step 2
target mean strength
target mean strength = fck+1.65*S
=35+1.65*5=43.25n/mm2
where S is standard devision table 8 is456
step 3
w/c ratio
max w/c ratio is 0.45 from table 5 is456
from is10262-2019 w/c and compressive strength fig1 given w/c ratio is 0.38
0.38<0.45 so adopt w/c ratio is 0.38
step 4
calculation of water content
from is10262 max water content is 186lit(25mm to 50mm slump range)
for 125mm slump = 186 *9/100 +186=203lit
as superplastcier used water content redused upto 30% and based on trial water content reduction of 29% is achived with plasicizer
arrived water content is =203 * 0.71 =144 lit
step 5
cement content calculation
cement content =water used/w/c ratio=144/0.38=379kg/m3
calculated cement content is more than minimun cement content so arrived cement content is accepted.
fly ash is usual to increase the cementitious material by some percentage, for ex incresse of 10%
cementitious content 379*1.1=417kg/m3
let us % of flyash 30% to cementitious material = 30/100 * 417=125 kg/m3
cement = 417-125=292kg/m3
w/c is =144/417 =0.35
saving of cement =87kg/m3
step 6
calculation of CA & FA
volume of CA 20mm size & FA table 5(zone 1) of 10262 is0.5=0.6
in present case w/c ratio is 0.38 therefore the CA is increse to decrese FA
w/c of CA =0.6 +[(0.01/0.05 )*0.12]=0.624
for pumpable concrete CA reduced 10%
volume of CA =0.624 * 0.9=0.562
volume of FA =1-0.56=0.438
step 7
mix calculation
volume of concrete = 1m3
volume of cement= [292/(3.15*1000)]=0.093m3
volume of flyash = [125/(2.2*1000)] =0.057m3
volume of water = 144/1000= 0.144m3
volume of chemical admixture = (1.2/100)*417=5kg/m3
= (5/1.1)*(1/1000)=0.005m3
volume of agg(CA+FA) =[1-0.093-0.057-0.144-0.005]=0.701m3
mass of CA =0.701*0.562*2.74*1000=1080kg/m3
mass of FA= 0.701*0.438*2.74*1000=842kg/m3
step 8
mix proportion
cement =292kg/m3
fly ash =125kg/m3
water =144kg/m3
FA =842kg/m2
CA =1080kg/m3
w/c ratio =0.35
mix ratio = 1:2.01:2.59
step 9
filed correction
FA = 842kg/m3
no absorbtion & moisture1%
quantity of surface moisture is= [1/100 ]* 842 = 8.42kg
weight of FA in field condition = 850.42 and say 851kg/m3
water absorbtion of CA =1080 * [0.5/100]=5.4
so weight of CA in field condittion=1080-5.4=1074.6 and say 1075kg/m3
1 .m50 grade concrete mix design
aim
mix design for m50 concrete design
step 1
type of mix=design mix
grade designation=50
type of cement=opc 53 (is1226)
max nominal size of agg=20mm
minimum cement content=340kg/m3(is456,table-5)
max w/c ratio=0.45 asper table 5 is456
workability=100mm slump
exposure=very severe
method of concrete=pumping
degree of supervision=good
agg type=angular
superplaticizer used
maximum cement content=450kg/m3
sp.gravity of cement=3.15
sp.gravity of CA=2.74
sp.G of FA=2.74
water absorbtion CA=0.5%
surface moisture FA=1%
step 2
target mean strength
target mean strength = fck+1.65*S
=50+1.65*5=58.25n/mm2
where S is standard devision table 8 is456
step 3
w/c ratio
max w/c ratio is 0.45 from table 5 is456
from is10262-2019 w/c and compressive strength fig1 given w/c ratio is 0.34
0.34<0.45 so adopt w/c ratio is 0.34
step 4
calculation of water content
from is10262 max water content is 186lit(25mm to 50mm slump range)
for 100mm slump = 186 *6/100 +186=197lit
as superplastcier used water content redused upto 30% and based on trial water content reduction of 29% is achived with plasicizer
arrived water content is =197 * 0.71 =140 lit
step 5
cement content calculation
cement content =water used/w/c ratio=140/0.34=411kg/m3
calculated cement content is more than minimun cement content so arrived cement content is accepted.
step 6
calculation of CA & FA
volume of CA 20mm size & FA table 5(zone 1) of 10262 is0.5=0.6
in present case w/c ratio is 0.34 therefore the CA is increse to decrese FA
w/c of CA =0.6 +[(0.01/0.05 )*0.16]=0.632
for pumpable concrete CA reduced 10%
volume of CA =0.632 * 0.9=0.569
volume of FA =1-0.569=0.431
step 7
mix calculation
volume of concrete = 1m3
volume of cement= [411/(3.15*1000)]=0.131m3
volume of water = 140/1000= 0.140m3
volume of chemical admixture = (1.2/100)*411=4.9kg/m3
= (5.9/1.1)*(1/1000)=0.005m3
volume of agg(CA+FA) =[1-0.131-0.140-0.005]=0.724m3
mass of CA =0.724*0.569*2.74*1000=1129kg/m3
mass of FA= 0.724*0.431*2.74*1000=855kg/m3
step 8
mix proportion
cement =411kg/m3
water =140kg/m3
FA =855kg/m2
CA =1129kg/m3
w/c ratio =0.34
mix ratio = 1:2.08:2.74
step 9
filed correction
FA = 855kg/m3
no absorbtion & moisture1%
quantity of surface moisture is= [1/100 ]* 855 = 8.55kg
weight of FA in field condition = 863.55 and say 864kg/m3
water absorbtion of CA =1129 * [0.5/100]=5.65
so weight of CA in field condittion=1080-5.65=1123.35 and say 1124kg/m3