Project on Concrete Mix Design for various grades of Concrete
Aim & Introduction -:Concrete mix design
1.Concrete is a complex material and has the right mix of constituents of concrete which if not done proparly and Will have advese effect on the properties of concrete
2. Concrere mix design is a systematic process of choosing economical reletive Propration of various ingredients from availabale material that gives the concrete of desired workability
3.the proccess of selecting Suitaibale ingredients producing concrete of requred strength durability and workability as economical as possible is known asconcrete mix design
4.The Compessive strength of the concrete depend on the quality and quantity of cement water and aggregate
5.It also depends on the mixing batching placing Compaction and curring
Procedure in detail
The Concrete Mix Design for M35 grade concrete without Fly ash
Grade of concrete
1. The grade in cement correspondeds to the average compressive strength attained in 28days .Here "M" Represents the mix of concrette and the Number Represents the compressive strength attained in N/mm^2
From table 1 of Is 10262:2009 Standard daviation S=5N/mm^2
There for targate strength =50+1.5*5=58.25N/mm^2
1. Selection of water cement ratio
From Table 5 Is 456:2000 for severs exposure Maximum water cement ratio =0.45 based on expreience adopted water cement ratio is 0.40
0.40 <0.45 , hance ok,
2.Selection of water content
from table 2 of Is 10262:2009 Maximum water content for 20mm Aggregate=186liter (for 25mm to 50mm slump rang)
3.Eatimate water content for 100mm slump= 186+6/100*186=197liter
As superplasticizer is used the water content can be reduced up to 20% and above based on trails water content reduction of 29%is achived with palsticizer hence the arrived water content =197*0.71=140liter
4.Calculation of cement content
Watre cement ratio =04
cement content = 140/0.4=350kg/m^3
from table of Is 456 minimum cement content for svere exposure condition =320kg/m^3
350kg/m^3>320kg/m^3 hence ok
1. The percentage of fly ash needs to be decided based on project requrement and quality of material
2. In some cases increase in cementitious materials be warranted incease in cementitious material and trial (this example is with increase of 10% cementitious material content)
cementitious material content =350*1.10=385kg/m^3
Water content =140kg/m^3
So water cement ratio =140/385=.364
Fly ash @30% total cemeltitous material content =385*30%=115kg/m^3
cement (OPC) = 385-115=270kg /m^3
Saving of cement while using fly ash=350-270=80kg/m^3
Fly ash being utilized =115kg/m^3
The Concrete Mix Design for M50 1:grade concrete with fly ash
data collection
grade of concrete =M50
Exposure condition = moderate
Grade of cement =M33(opc)
Fck=50N/mm^2
Targete mean strength of concrete ft= Fck+1.65s
=50+(1.65*5) =58.25 N/mm^2
Total mean strength of concrete =58.25N/mm^2
10. List out the difference between design mix and nominal mix concrete?
Result -:1:1.5:8