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
Ans.
Aim: To calculate the concrete mix design for M35 grade concrete with fly ash and M50 grade concrete without fly ash.
INTRODUCTION
Concrete mix design is the method of finding the precious proportion of Cement,sand and aggregate for concrete to achieve the target strength in structure, therefore concrete mix design can be started as concrete mix design can be started as concrete mix in terms of cement, sand, aggregates.The design is done according to the requirements of concrete strength,so We can achieve the deseriable properties of concrete either itis in fresh stage or in hardened stage.The fresh concrete properties like workability, settings time and hardening concrete properties like compressive strength, durability etc.are attend surely by this method.use of additives like admixtures,retarders etc.other than basic ingredients are used to improve the properties of mix. This project consist of two parts,the first part deals with the Design of M35grade cement with fly ash as a part of it and second part is the design of M50 grade concrete without fly ash.
OBJECTIVE
The objective of this project is to produce a mix design for M35 grade concrete containg fly ash and M50 grade concrete.The mix will be prepared as per is Method.concrete mix proptioning guidelines from IS10262:2009and recommend guide lines from IS10262:1982
EQUATION USED
1.Target mean strength
f'ck=fck+1.65s
Where
f'ck= traget average compressive strength at 28 days
fck=characteristics compressive strength at 28days,and
s= standard deviation
2.cement content
Cement content=water content/warer cement ratio
3.Volume calculations
a)vol.of concrete
b) vol of cement=[mass of cement]/[specific gravity of cement]×1/1000
c) vol of water=[mass of water]/[specific gravity of water]×1/1000
d) vol.of chemical admixtures= mass of admixtures/specific gravity of admixtures ×1/1000
e)vol.of all in aggregrates= (a-b+c+d)
f)mass of course aggregates=ex vol.of course aggregates ×specific gravity of fine aggregate ×1000
g) mass of fine aggregate ×e×vol.of fine aggregate ×specific gravity of fine aggregate ×1000
Part 1:
To calculate the concrete mix design for M35 grade concrete with fly ash
M35 grade concrete with fly ash
Step 1: stipulation for concrete design mix
Grade designation. M35
Types of cement . OPC 43 grade confirming to IS 8112
Types of minerals admixtures. Fly ash confirming to IS3812 part 1
Max.cement content. 320kg/m3 table 5 IS456:2000- exposure condition.
Max.water content ratio. 0.45 table 5 of IS 456:2000 exposure condition.
Workability. 100 mm slump value for pumpable concrete.
Exposure condition. Severe ( for reinforcement concrete)
Method of concrete placing. Pumping.
Degree of supervision . Good
Types of aggregate. Crushed angular aggregates
Maximum cement content. 450 kg/m3
Chemical admixtures. Super plastcizer
STEP 2.....
TEST DATA FOR MATERIAL
cement used. OPC 43 grade confirming IS 8112
Specific gravity of cement. 3.15
Fly ash. IS 3812
Specific gravity of fly ash. 2.2
Chemical admixtures. Super plastcizer IS 9103
Specific gravity of course aggregates. 2.74
Specific gravity of fine aggregate. 2.74
Water absorption of course aggregates. 0.5%
Water absorption of fine aggregate. 1.0%
Free surface moisture of course aggregates. Nill
Free surface moisture of fine aggregates. Nill
STEP 3.
Traget strength for mix proptioning..
f'ck= f'ck+1.65s
Where
f'ck =target average compressive strength at 28 days
S = standard deviation
Target mean strength= 43.25 N/mm2
STEP 4...
the maximum water cement ratio to design M50 grade concrete can be found from table 5 of IS 456-2000.
0.44<0.45, hence ok
Adopted w/c ratio= 0.44
STEP 5.
SELECTION OF WATER CONTENT...
From table 2 of IS 10262: 2009, maximum 186litre.
Here water required 158liters
Step 6.
Calculation of cement and fly ash required...
Adopted w/c = 0.44
Cementitious material, cement and fly ash required is 395kg/m3,277kg/m3 and 118kg/m3 and the new water -cement ratio is 0.4respectively..
Step 7.
From table 3.of IS 10262:2009
Volume of fine aggregate and course aggregates is 0.431 and .568
Step 8. Mix calculation..
Vol.of concrete. 1m3
VOC. 0.087m3
Vol.fly ash. 0.053
Vol.of water. 0.158m3
Vol.of chemical admixtures. 0.006m3
Vol.of aggregate. 0.696m3
Mass course aggregates. 1077kg/m3
Mass of fine aggregate. 822kg/m3
Step 9. Mix proportion..
Cement 277kg/m3
Fly ash 118kg/m3
Water 158 I/m3
F.a 822kg/m3
C a 1077kg/m3
Chemical admixtures 7.18.kg/m3
Water cement ratio 0.4
Mix proportion by weight 1:2:0.8:2.72
Part 2..........
To calculate the concrete mix design for M50 grade concrete without fly ash.......
Step 1. Stipulation for concrete design mix
Grade designation M50
Types of cement OPC 53 grade
Maximum nominal size of aggregate 20 mm
Step 2. Test data for material
Step 3. Target strength for mix proportion
Target mean strength= 58.25 N/mm2
Step 4.selection of water -cement ratio.
Adopted W/C ratio= 0.44
Step 5. Selection of water content..
Water required 158 litres..
EP6: CAL.OF CEMENT REQUIRED
cement required is 359kg/m3
Step 7.vol.of course aggregates and fine aggregate content..
Vol.of fine aggregate and course aggregates is 0.431 and.568.
Step 8. Mix calculation..
A. Volume of concrete 1m3
B. Vol.of cement. 0.114m3
C vol.of water. 0.158m3
D. Vol.of chemical admixtures. 0.006m3
E. Vol.of all in aggregrates 0.722m3
Mass of fine aggregate. 821kg/m3
Mass of course aggregates. 1123kg/m3
Step 9. Mix proportion..
Mix proportion by weight.. 1:2.28:3.12
RESULTS........
Mix proportion by weight of M35 grade of concrete with fly ash is 1:2.08:2.72 and it's water - cement ratio was found to be 0.4
Mix proportion by weight of M50 grade of concrete without fly ash is 1:2.28:3.12 and its water cement ratio was found to be 0.44.