Engineering Mechanics Chapter 5 Equilibrium of a Rigid Body
CONCRETE MIX DESIGN AS PER IS 10262:2009
1. Concrete Mix Design IS 10262:2009
A K GUPTA
EXECUTIVE ENGINEER (TRAINING)
14/02/2017
2. Introduction
• Concrete Mix Design means, determination of
the proportion of the concrete ingredients i.e.
Cement, Water, Fine Aggregate, Coarse
Aggregate which would produce concrete
possessing specified properties such as
workability, strength and durability with
maximum overall economy.
3. Types of Concrete Mixes
1. Nominal Mixes –
• These mixes are of fixed cement-aggregate ratio.
• These offer simplicity and under normal circumstances.
• Have a margin of strength above that specified.
2. Standard Mixes –
• The minimum compressive strength has been included
by IS-456:2000 in many specifications. These mixes are
termed standard mixes.
• E.g.: M10, M15, M20, etc.
3. Designed Mixes -
• In these mixes the performance of the concrete is
specified by the designer but the mix proportions are
determined by the producer of concrete, except that the
minimum cement content can be laid down.
4. Methods of Concrete Mix Design
• American Concrete Institute Method (ACI
Method)
• Road Note Number 4 Method
• DOE Method
• Indian Standard Method (IS Method)
7. Standard Deviation
• Number of test results of samples taken from
site-30
• Standard deviation for each batch if significant
changes in concrete batches
• Standard deviation to be brought upto date.
10. Selection of Mix Proportion
Clause 4.1
• Selection of Water cement ratio
• For the same water cement ratio ,the compressive
strength may differ according to different cement,
supplementary cemetitious materials, aggregate size,
grading, shape and surface texure.
• Preliminary w/c may be selected from established
relationship between w/c ratio and compressive
strength.
• Alternatively w/c ratio may be selected from table 5 of
IS: 456 for respective exposure condition.
17. Step2 Selection of water/cement ratio
Considering moderate exposure,
Max w/c = 0.5
Hence w/c = 0.38
w/c = 0.38
18. 4.2 Selection of Water content
Water content is influenced by……..
• Aggregate size
• Shape
• Texture
• Workability
• w/c ratio
• Other supplementary cementitious material
• Admixture
• Environment conditions
20. Selection of water content
Water content in table -2 is for
• Angular coarse aggregate ,
• - 10 kg for sub angular aggregate
• -20 kg for gravel with some crushed particles.
• -25kg for rounded gravel
• Slump-25to 50mm, increase by 3 % for every
additional slump of 25mm.
21. Water content for admixtures
• -5 to -10% for water reducing admixtures
• -20% for superplasticisers.
22. Water reducers
• At constant workability –
The reduction in mixing water is expected to be
of the order of 5% to 15%.
Naturally increases the strength.
• At constant w/c ratio –
Increased workability.
Slump of 30mm to 150 mm.
23. Water reducers
1.Thin walls of water retaining structures with
high percentage of steel reinforcement
2.Deep beams, column and beam junctions
3.Tremie concreting
4.Pumping of concrete
5.Hot weather concreting
6.Concrete to be conveyed for considerable
distance and in ready mixed concrete
industries
24. Super Plasticisers
Superplasticizers constitute a relatively new
category and improved version of plasticizer, the use of
which was developed in Japan and Germany during 1960
and 1970 respectively. They are chemically different from
normal plasticisers.
Classification of Superplasticizers:
Sulphonated malanie-formaldehyde condensates (SMF)
Sulphonated naphthalene-formaldehyde condensates
(SNF)
Modified lignosulphonates (MLS)
Other types
26. Superplasticisers
Permits reduction of water content about
30% without reducing the workability
It is possible to use w/c ratio as low as 0.25 or
even lower and yet to make flowing concrete
to obtain strength of order 120 Mpa or more.
• Production of high strength and high
performance concrete
• Production of flowing, self levelling, self
compacting concrete
27. Step3 Selection Of Water Content.
• From table – 2, IS-10262:2009
(For 20mm nominal max. size of aggregate & 25 to
50mm slump)
Max WC = 186 kg/m3
# Correction for slump in water content (according to
clause 4.2, IS:10262)
Slump = 100 mm
Correct WC for 100 mm slump = 186 + 6%
= 197.16 kg
197 kg of water per m3
of concrete
28. 4.3 Calculation of cementitious
Material content
• Calculate cementitious material from the
water cement ratio and the quantity of water
per cum(water content)
• Check it from durability requirement .
• Select higher value
• The maximum as per IS 456
32. Coarse aggregate proportions
• Table -3 is for water cement ratio of 0.5,
proportion may be suitably adjusted for other
water cement ratio.(@-or+.01 for every
change in water cement ratio of .05)
• For given workability ,the volume of coarse
aggregate depends upon its nominal max size
and grading zone of fine aggregate.
• Reduce the estimated CA content by 10% if
pumping is to be done. It should be
consistent with IS 456 and meet project
34. 4.6 Estimation of Fine aggregate
Proportion
• Find out the absolute volume of cementitious
material, water and chemical admixture by dividing
their masses by their respective specific gravity and
multiplying by 1/1000.
• Subtract the result of summation above from unit
volume. Find volume of total aggregates
• Divide coarse and fine aggregate fractions by volume
as per clause 4.4.
• Find CA and FA by multiplying their volumes with
respective specific gravities and multyplying by 1000.
35. Step 5: Selection of Proposition of
Volume of Coarse Aggregate
From table 3,(IS-10262:2009) for zone IIIrd
of F.A.
Maximum size of aggregate = 20 mm.
Vol. of CA per unit vol. of total aggregate = 0.64
# For 0.1 decrease in w/c & increase in CA by 0.02
Applying correction of 0.024
Vol. of CA = 0.64 + 0.024
=0.664m3
Total aggregate = 1
CA = 0.664m3
FA = 0.336m3
36. Quantities by volume
• Cement—518.42/(3.15*1000)=.165 cum
• Water ----197/(1*1000)=.197cum
• Aggregates -----1-(.165+.197)=.638 cum
• CA-------------.638*.664=.4236cum
• FA----------------.638*.336=.214 cum
37. Quantities by Mass
• Cement-----518.42 kg
• Water ----------197 kg
• CA--------------.4236*2.74*1000=1161.76kg
• FA------------.214*2.74*1000=586.36 kg
38. Step6 Mix Calculation Results:
Mass of
Cement
Water F.A. C.A.
518.42 197 586.36 1161.76
1 0.38 1.13 2.24
Ratio Obtained
1 : 1.13 : 2.24
Ratio Obtained
1 : 1.13 : 2.24
39. Trial Mixes
• Check the workability of trail mix-1. Free from
segregation and bleeding .See finishing properties;
• If not satisfactory . Trial mix-2 with varying water and
admixture keeping pre-selected value of water
cement ratio.
• Trial mix 3 and 4 with same water content as that of
mix-2 but varying water cement ratio.
• Find relationship between compressive strength and
w/c ratio.
• Field trails