Effect of time delay in mixing on mix design of m30 grade concrete.

EFFECT OF TIME DELAY IN MIXING ON MIX DESIGN
OF M 30 GRADE CONCRETE
A Project Report submitted in
Partial fulfillment of requirements for the degree of
Bachelor of Technology
In
Civil Engineering
By
Nitish Raj Rai (201918511)
Bhupesh Adhikari (201918508)
Pangkaj Khanal (201918507)
Under the supervision of
Mr. TAMAL GHOSH
Assistant Professor
DEPARTMENT OF CIVIL ENGINEERING
SIKKIM MANIPAL INSTITUTE OF TECHNOLOGY
(A constituent college of Sikkim Manipal University)
June, 2022

1
DECLARATION
We, the undersigned, hereby declare that the work recorded in this project report entitled “Effect
of time delay in mixing on mix design of M 30 grade concrete” in partial fulfillment for the
requirements of award of B. Tech (CE) from Sikkim Manipal Institute of Technology (A
constituent college of Sikkim Manipal University) is a faithful and bona fide project work carried
out at “Sikkim Manipal Institute of Technology” under the supervision and guidance of Mr. Tamal
Ghosh of Sikkim Manipal Institute of Technology.
The results of this investigation reported in this project have so far not been reported for any other
Degree / Diploma or any other technical forum.
The assistance and help received during the course of the investigation have been duly
acknowledged.
Name of Student-Nitish Raj Rai (Reg 201918511)
Name of Student-Bhupesh Adhikari (Reg 201918508)
Name of Student-Pangkaj Khanal (Reg 201918507)

2
BONA FIDE CERTIFICATE
This is to certify that the project titled “EFFECT OF TIME DELAY IN MIXING ON
MIX DESIGN OF M 30 GRADE CONCRETE” is a bona fide record of the work done
jointly by
Mr. NITISH RAJ RAI (201918511)
Mr. BHUPESH ADHIKARI (201918508)
Mr. PANGKAJ KHANAL (201918507)
of Civil Engineering Department of SIKKIM MANIPAL INSTITUTE OF
TECHNOLOGY, MAJHITAR in partial fulfillment of the requirements for the award of
Bachelor of Technology in Civil Engineering.
Signature of the Supervisor
Department of Civil Engineering
Sikkim Manipal Institute of Technology
Signature of HOD
Department of Civil Engineering
Sikkim Manipal Institute of Technology
Major Project Viva held on:13th
June 2022
Signature of Dept. Project Coordinator Signature of External Examiner

3
ACKNOWLEDGEMENT
We would like to convey a heartily gratitude to our project guide Mr. Tamal Ghosh (Assistant
Professor) for the consent support and guidance in our project. We are also grateful for the support
and ideas provided by our senior students.
We would like to thank Dr. Chandrashekhar Bhuiyan(HOD) for giving us the opportunity to work
and present our project work.
The success and final outcome of this project required a lot of guidance and assistance from many
teachers and we are extremely fortunate to have all this along with the completion of our project
work. We are highly indebted to Sir Tamal Ghosh for the guidance and constant supervision as
well as providing necessary information about this project.
We own our profound gratitude to all our teachers who have been our constant support for making
this project a successful one. We also thank all the lab technicians and staff of Sikkim Manipal
Institute of Technology who helped us in the completion of our project work.

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ABSTRACT
In the report, a brief analysis about the time delaying effect in concrete mix design for M30 grade
has been observed. The test was performed by using Ramco OPC 53 grade cement. Also results
for specific gravity of fine and coarse aggregates simultaneously, the zones of aggregates were
computed. A trial was conducted for mixing periods of 5 minutes and 1 hour. A collapse slump is
observed in the first trial because it was a highly workable mix. A true slump was achieved in the
second and third trial. The strength for the first trial was not achieved due to an increase in the
water-cement ratio. We obtained the target strength for M 30 grade of concrete for 28 days in the
second and third trial. The theory listed in this report along with the numerical can be continued
for further research’s.

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LIST OF FIGURES
SL
NO.
NAME OF FIGURE PAGE
NO.
1 Empty pycnometer(W1) 20
2 Pycnometer + sand(W2) 20
3 Pycnometer + sand + water(W3) 20
4 Pycnometer + water(W4) 20
5 Empty pycnometer(W1) 22
6 Pycnometer + aggregate(W2) 22
7 Water + W2(W3) 22
8 Pycnometer + water(W4) 22
9 Sieves for fine aggregate 24
10 Sieves for coarse aggregates 25
11 Coarse aggregates 25
12 Types of slump 43
13 Freshly casted cubes 46
14 Cubes after test 46

6
LIST OF SYMBOLS
Abbreviation Meaning
fck Characteristic compressive strength
K Statistical constant
s Standard deviation
m3 Meter cube
mm2 Millimeter square
kN Kilo Newton
kg kilogram
g Specific gravity
% Percentage
mm Millimeter

7
LIST OF TABLES
SL
NO.
NAME OF TABLE PAGE
NO.
1 Specific gravity of the specimen on different condition 18
2 Specific gravity of sand on different condition 19
3 Average specific gravity of coarse aggregate on different condition 21
4 Sieve analysis of fine aggregate on different condition 23
5 Sieve analysis of coarse aggregate on different condition 24
6 Stipulation for proportioning 29
7 Test data for material 30
8 Mix proportioning formulation and important clauses 30
9 Mix Proportion for the first trial( After all the necessary adjustment) 31
10 Test Results 31
15 Test Results 37

8
20 Test Results 42
21 Test results for 1st
trial 47
22 Test results for 2nd trial 48
23 Test results for 3rd trial 48

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TABLE OF CONTENTS
CHAPTERS PAGE NO.
Declaration by student 1
Certificate by supervisor 2
Acknowledgement 3
Abstract 4
List of figures 5
List of symbols 6
List of table 7-8
01. INTRODUCTION 11
1.1 General 11
1.2 Scope of present work 11
1.3 Objective of present work 12
02. LITERATURE REVIEW 13
2.1 Overview 13
2.2 Concrete mix design as per IS 10262:2019 13
2.3 Chetan Isal, Swati Ambedkar; Study of various grade of concrete
with and without admixture, International journal for research in
applied science and engineering technology, 2020
13
2.4 Venu Malagavelli, Neelkanteswara Rao Paturu; strength and
workability characteristics of concrete by using different super
plasticizer, International journal of materials engineering, 7-11-
2012
14
03. METHODOLOGY 15
3.1 Concrete mix design 15
3.2 Factors to be considered for mix design 15-16
3.3 Requirements of concrete mix design 16
3.4 Factors affecting choice of mix proportion 16-17
3.5 Procedure for concrete mix design 17

10
3.6 Test for specific gravity of cement 18
3.7 Test for specific gravity of fine aggregate 19-20
3.8 Test for specific gravity of coarse aggregate 21-22
3.9 Sieve analysis of fine aggregate 23-24
3.10 Sieve analysis of coarse aggregate 24-25
3.11 Design calculation of M 30 using OPC with 5 min mixing 26-31
3.12 Design calculation of M 30 using OPC with 1 hr mixing 32-37
3.13 Design calculation of M 30 using OPC with 5 min mixing 38-42
3.14 Procedure of slump test for M 30 grade concrete 43
3.15 Procedure for M 30 with 5 min of mixing time 43-44
3.16 Procedure for M 30 with 1 hour of mixing time 44
3.17 Concrete cube casting procedure 45-46
04. RESULT 47-48
05. CONCLUSION 49
REFERENCES 50

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CHAPTER
1
INTRODUCTION
1.1GENERAL
Concrete mix design comprises of selection of different ingredients of concrete with relative
amounts such that the concrete produces the desired strength, workability and durability with
economic considerations. The two stages namely the plastic and the hardened stage governs the
performance of proportioned ingredients of concrete. The concrete cannot be properly placed and
compacted if the concrete in the plastic stage doesn’t have the proper workability. Therefore,
workability of concrete plays a vital role in concrete mix design.
The compressive strength of hardened concrete is depended upon number of factors like, water
cement ratio, quality of cement, shape and size of aggregates, batching, mixing, placing,
compaction and curing. The cost of concrete is dependent upon cost of material and labour. The
cost of cement make up a major component of concrete which leads to production of a lean mix
of concrete. Also considering the use of a rich mix can lead to a highly shrinkable concrete and
cracks may be develop in the structure due to increased heat of hydration in the concrete.
One of the major factors considering concrete is the cost. Therefore, the cost of the material
required for production of minimum mean strength of concrete is termed characteristic strength
for the structure. The concrete depends on the quantity control but this factors also increases the
cost of concrete. Economically, the extent of quality control is compromised depending on the
type and scale of the construction work. The workability of the concrete mix is directly
proportional to the cost of labour.
1.2 SCOPE OF PRESENT WORK
The area of work that has been foreseen in this project is the study of strength of compacting
strength of concrete with the use of the aggregates easily available in this area. Focus has been
given only upon the general strength development of concrete mix design.

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1.3 OBJECTIVE OF PRESENT WORK
➢ To design the M30 grade of concrete targeting 100mm slump workability.
➢ To visualize the effect of 1hour time delay during mixing in the mix design.
➢ Concrete mix design of M30 grade concrete (M30 has been selected because through a
general study it has been found out that M30 mixes are generally used in the Sikkim
region).
➢ Test of development of strength by the use of admixture, along with normal design mix of
M30 grade concrete has been conducted using ordinary portland cement 53 grade.
➢ Test for ordinary portland cement the mixing periods for 5 minutes in the first trial and
third trial and 1 hour for the second trial has been conducted taking consideration for
transportation of the concrete.
➢ Taking the various design mixes for the respective strengths developed in 7 days, 14 days
and 28 days the results have been achieved.

13
CHAPTER
2
LITERATURE REVIEW
2.1 OVERVIEW
This chapter deals with various research works done on concrete mix design and the effects of
admixture for achieving target strength at short span of time.
2.2 CONCRETE MIX DESIGN AS PER IS 10262:2019
The Indian standard code IS 10262:2019 presents guidelines for a design for a normal concrete.
The basic assumptions taken in the concrete design is that compressive strength of concrete is
influenced by water-cement ratio. In this method water-cement ratio is dependent upon a grade of
concrete and type of exposure. Water content selected on the basis of nominal coarse size aggregate
and slump. And the volume of coarse aggregate depends on the zone of fine aggregate as per IS
383.
2.3 CHETAN ISAL, SWATI AMBEDKAR; STUDY OF VARIOUS GRADE
OF CONCRETE WITH AND WITHOUT ADMIXTURE, INTERNATIONAL
JOURNAL FOR RESEARCH IN APPLIED SCIENCE AND ENGINEERING
TECHNOLOGY, 2020
The ingredient of concrete are mixed in different proportions, either by volume or by weight, the
latter being more precise and scientific. Volume batching of concrete is not allowed by revised IS
456:2000 today and the common method of expressing the proportion of ingredients in concrete
mix is in the form of parts or ratio of cement. The fine aggregate and coarse aggregate cement
being taken as unity. Cubes are cured alternate wetting and drying condition(partially curing)
average compressive strength of cube 30.60N/mm2
.Which is approximately 60% of the targeted
compressive strength. Therefore if the curing is not carried out in site, the grade of concrete used
is M 30 then the actual strength obtained at site.

14
2.4 VENU MALAGAVELLI, NEELKANTESWARA RAO PATURU;
STRENGTH AND WORKABILITY CHARACTERISTICS OF CONCRETE
BY USING DIFFERENT SUPER PLASTICIZER, INTERNATIONAL
JOURNAL OF MATERIALS ENGINEERING, 7-11-2012
Concrete is a composite material made with cement aggregates, admixture and water comprises in
quantity the largest of all man-made material. Although aggregates make up 3/4th
of the volume
of concrete, the active constituent of concrete is cement paste. The properties and performance of
concrete is determined by the properties of the cement paste. Super-platicizer in concrete confer
some beneficial effect such as acceleration, retardation, air entrainment, water reduction, plasticity,
etc and these affect are due to their action on cement. In the present experimental investigation M
30 concrete is used as control mixer with four different plasticizer namely, Sulphonated
Napthalene Polymer(SNP1), SNP2, SNP3 and SNP4. The strength of modified concrete is
compared with normal concrete i.e. concrete without super-plasticizer. The results show that
significant improvement in the strength and workability of modified concrete.

15
CHAPTER
3
METHODOLOGY
3.1 CONCRETE MIX DESIGN
The concrete mix design means selecting well suited materials for producing good quality concrete
and finding out their relative quantities
Different types of concrete mixes,
Nominal mix: Nominal mix comprises of mix proportion of the cement, sand and admixtures . In
nominal mix constituents of concrete are mixed on the basis of their volume.
Standard mix: The result for an under or over-rich mix of concrete is governed by the strength of
varying nominal mixes of fixed cement-aggregate ratio(by volume).
Design mix: The designer manipulates the performance of the concrete mix and the producer
determines the mix proportion of the concrete mix, with the exception of the minimum required
cement content is used. This is the most proper discipline required for the distinction of the mix
proportions along with certain materials that possesses varying unique characteristics.
According to IS 456:2000 Target mean strength:
where,
fck= Characteristic compressive strength at 28 days and, S= Standard deviation
3.2 FACTORS TO BE CONSIDERED FOR MIX DESIGN
1. The designated grade of concrete determines the characteristic strength required for concrete.
2. The compressive strength of concrete obtained is directly governed by the type of cement used.
3. The size of aggregates to be used for design should be within the limit provided by IS 456-
2000.

16
4. The quantity of cement to be used should be of proper proportion to avoid creep, shrinkage
and cracking.
5. A workable concrete to achieve good placing and compaction is also dependent on the size
and shape of the section, quantity and spacing of reinforcement and technique for placing and
compaction.
3.3 REQUIREMENTS OF CONCRETE MIX DESIGN
1. For a structure, the minimum compressive strength of the concrete is required.
2. A workable concrete is necessary to have a good compaction through the help of compacting
equipment.
3. For particular site condition water cement ratio should be such that it must give adequate
workability
4. Maximum cement content to avoid shrinkage, cracking due to temperature cycle in mass
concrete.
5. To avoid shrinkage and cracking in mass concreting due to temperature variation the cement
content should be maximum.
3.4 FACTORS AFFECTING CHOICE OF MIX PROPORTION:
1. Compressive strength
The mean compressive strength determines the nominal water-cement ratio of the mix at 28 days.
Some more factors affecting the strength of concrete at a given age and cured at a prescribed
temperature is degree of compaction.
2. Workability
Workability is dependent upon three factors namely, the size of the section to be concreted, the
amount of reinforcement, and the method of compaction. The narrow and complicated section with
numerous corners and inaccessible parts, the concrete must have a high workability because full
compaction can be achieved with reasonable amount of effort.
3. Durability
Durability of concrete is defined as how much resistance can be offered to aggressive environmental
conditions. A high strength concrete is more durable than low strength concrete. In these situations,
the high strength is not necessary but the conditions of exposure conditions affecting high durability
is vital, the requirement of durability determines the water-cement ratio.

17
4. Maximum nominal size of aggregate
For small cement requirement the greater is the maximum size of aggregate for a particular water-
cement ratio since the workability of concrete increases with the increase in maximum size of the
aggregate. However, the compressive strength tends to increase with the decrease in size of
aggregate.
IS 456:2000 and IS 1343:1980 recommend that the nominal size of the aggregate should be as large
as possible.
5. Grading and type of aggregate
The water-cement ratio and the workability is influenced by the grading of aggregates. A lean mix
can be acquired by having coarser graded aggregates. In order to make a good mix, lean mix of
increased percentile is not very desirable because there is insufficient fine materials which makes
the concrete cohesive. For a good aggregate-cement ratio of desired workability and water cement
ratio, the type of aggregate play an important role. The uniformity of grading of aggregates is
formed by mixing different sizes of aggregates. Therefore, uniformly graded aggregates form an
important component.
6. Quality Control
Quality control refers to how properly construction work is carried out in varying working
conditions. Through the variation in test results, the quality control can be estimated statically. The
cement content required for the mix will be lower if there is a low difference between the mean
and minimum strength of the mix. The factor that comprises of all these characteristics is known
as quality control.
3.5 PROCEDURE FOR CONCRETE MIX DESIGN
Before performing the design calculations we have to perform the following standard tests.
1. Test for specific gravity of cement (OPC 53 grade).
2. Test for specific gravity of fine aggregates.
3. Test for specific gravity of coarse aggregates.
4. Sieve analysis of Coarse aggregates and fine aggregates.

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3.6 TEST FOR SPECIFIC GRAVITY OF CEMENT
Apparatus: Le-Chatelier Flask, weighing balance, glass rod.
Materials required : Cement, Kerosene.
Procedure: Take the weight of dry specific gravity bottle with its stopper (W1). Add a cement
sample up to half of the flask and weigh with its lid (W2). Pour a small amount kerosene in a flask
containing a cement sample upto its graduated mark. To remove entrapped air mix it thoroughly
with glass rod and dry the flask from outside and weigh (W3). Empty the flask, clean it and refilled
with clean kerosene up till the graduated mark. Dry the outside of the flask and weigh (W4).The
apparatus are cleaned and returned to the laboratory.
Table 1:Specific gravity of the specimen on different condition
Weights Sample 1 Sample 2 Sample 3
Empty weight of the
bottle, W1
0.031 0.030 0.030
Weight of the bottle+
Cement, W2
0.048 0.046 0.045
Cement+ Kerosene,
W3
0.083 0.082 0.085
Weight of bottle
+Kerosene, W4
0.072 0.072 0.072
Calculation of specific gravity,
Sp. G =
W2−W1
(W4−W1)−(W3−W2)
= 3.1

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3.7 TEST FOR SPECIFIC GRAVITY OF FINE AGGREGATE
Apparatus: Pycnometer , weighing balance, dropper.
Material required : Sand, Water.
Procedure: Take the empty weight of pycnometer with its lid as (W1). Fill the sample of sand upto
half of a pycnometer and weigh it as (W2). Add water to the sand in the pycnometer till the top
of the cone and used dropper to remove entrapped air . Dry the outer side of pycnometer and
weigh (W3). Empty the pycnometer, clean it and refilled with clean water up till the top of the
cone and used dropper to remove entrapped air. Dry the outer side of pycnometer and weigh (W4).
The test apparatus were cleaned and returned to the laboratory.
Table 2:Specific gravity of sand on different condition
Empty weight of the
bottle, W1
546 546 546
Sand, W2
1080 1059 1070
Sand+ water, W3
1770 1768 1788
Weight of bottle
+Water, W4
1490 1490 1490
The formula used for calculation of specific gravity is,
Sp. G =
W2 − W1
(W4 − W1) − (W3 − W2)
=2.2

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Fig 1:Empty pycnometer(W1) Fig 2:Pycnometer+sand(W2)
Fig 3:Pycnometer+sand+water(W3) Fig 4:Pycnometer+water(W4)

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3.8 TEST FOR SPECIFIC GRAVITY OF COARSE AGGREGATE
Apparatus: pycnometer, weighing balance, dropper.
Material required: Coarse aggregate, water.
Procedure: Weigh a clean and dry pycnometer (W1). Place a sample of coarse aggregate upto half
of a pycnometer and weigh it (W2). Add water to the coarse aggregate in pycnometer till the top
of cone and used dropper to remove entrapped air. Dry the pycnometer and weigh (W3). Empty
the pycnometer, clean it and refilled with clean water up till the top of cone and used dropper to
remove entrapped air. Wipe dry the pycnometer and weigh (W4). The test apparatus were cleaned
and returned to the laboratory.
Table 3: Average specific gravity of coarse aggregate on different condition
Empty weight of the
bottle, W1
546 546 546
Coarse Aggregate,
W2
1067 1248 1139
Coarse Aggregate +
Water, W3
1798 1930 1858
Weight of bottle+
Water , W4
1490 1490 1490
The formula used for calculation of specific gravity is,
Sp. G =
W2−W1
(W4−W1)−(W3−W2)
= 2.58

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Fig 5:Empty pycnometer(W1) Fig 6:Pycnometer+aggregate(W2)
Fig 7:Water+W2(W3) Fig 8:Pycnometer+water(W4)

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3.9 SIEVE ANALYSIS OF FINE AGGREGATE
Apparatus: Sieve size of 4.75mm, 2.36mm, 1.18mm, 600 micron, 300 micron, 150 micron, pan.
Calculation:
Table 4:Sieve analysis of fine aggregate on different condition
IS
sieve
size
(mm)
Weight of aggregate retained Percentage
of total
weight
retained
(%)
Cumulative
percentage
of total
weight
retained
(%)
Percentage
passing
(%)
Permissible
percentage
as per IS
283 (%)
Trail
1
Trail
2
Trail
3
Average
4.75 6 8 9 7.7 0.77 0.77 100 100
2.36 13 13 14 13.3 1.33 2.67 99.23 90-100
1.18 62 66 81 69.7 6.97 9.04 97.93 75-100
0.6 404 485 517 468.7 46.87 55.91 90.96 55-90
0.3 360 307 273 313.3 31.3 87.21 44.09 35-59
0.15 106 82 76 88 8.8 96.01 2.79 8-30
0.075 49 39 30 39.3 3.93 nil 3.99 0-10
Fineness modulus =
251.01
100
= 2.51(fine sand)

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Fig 9:Sieves for fine aggregates
3.10 SIEVE ANALYSIS OF COARSE AGGREGATE
Apparatus: Sieve size of 20mm, 12.5mm, 10mm and 4.75mm
Calculation:
Table 5:Sieve analysis of coarse aggregate on different condition
IS sieve
size
Weight of aggregate retained Percentage of
total weight
retained (%)
Cumulative
percentage of
total weight
retained (%)
Percentage
passing (%)
Trail
1
Trail
2
Trail
3
Average
20 2.13 2.50 2.067 2.23 44.6 44.6 55.4
12.5 2.59 2.18 2.58 2.45 49 93.6 6.4
10 0.21 0.26 0.24 0.23 4.6 98.2 1.8
4.75 0.053 0.064 0.078 0.07 1.4 99.6 0.4

25
Fineness modulus =
33.78
100
+ 5
= 8.378>5(Good)
Fig 10:Sieves for coarse aggregates
Fig 11:Coarse aggregates

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3.11 DESIGN CALCULATION OF M30 USING OPC WITH 5 MIN
MIXING
i) Strength of mix proportion,
fck= fck+ 1.65 x S
=30 + 1.65 x 5
=38.25 N/mm2
Fck=fck+ X
=30 + 6.5
=36.5 N/mm2
⸪ 38.25 N/mm2
is the higher value, the target value will remain constant.
ii) Approximate air content,
For 20 mm aggregate air content =10%(Table 3)
iii) Water-cement ratio selection,
For target strength of 38.25KN/mm2
the free water ratio is 0.45 for OPC 53 grade curve.
⸫ As per the table 5 of IS 456:2000, the maximum value of 0.45 is prescribed for severe exposure
for reinforced concrete.
The value will be attained greater than 0.45 in graph(fig 1) approximately as 0.48. Therefore, our
value is greater than 0.45 which the maximum prescribed.
⸫0.45 is taken
iv) Water content selection,
Water content =186kg (for 200mm slump) for 20mm aggregate.(By referring to table 4)
Required water content for 200mm slump.
=186 + 18 x 186/100= 219.48 kg ᵙ 220 kg
As admixtures (super plasticizers is used to reduce water content). On the basis of data obtained,
the water content can be reduced . On the basis of trial data, the water content reduced to 23% is
considered by the use of super plasticizer at the rate of1% by weight of cement.
Hence, the water content=219.48 x 0.77= 168.99 kg ᵙ169kg
v) Cement content calculation,
Water cement ratio = 0.45
Cement content = 169/0.45 =375.5 kg/m3
ᵙ 376kg/m3
(Should not exceed 450kg/m3
)

27
Minimum cement content for severe exposure condition = 320kg/m3
(From table 5 of IS
456:2000)
⸫ 376 kg > 320kg/m3
and 376 kg < 450kg/m3
hence, OK.
vi) Volume of coarse aggregate and fine aggregate content.
As per table 5 of IS 456:2000, the proportionate volume of coarse aggregate corresponding to 20
mm size aggregate and fine aggregate (Zone II) for water-cement ratio of 0.5 = 0.62
Water-cement ratio is 0.45.
Corrected volume of coarse aggregates for the water/cement ratio of 0.45 = 0.62 + 0.01 = 0.63.
Vol of fine aggregates content = 1- 0.63 = 0.37.
vii) Mix proportion calculation,
➢ Total volume = 1m3
➢ Entrapped air in wet concrete = 0.01m3
➢ Volume of cement,
= Weight of cement/specific gravity of cement x 1/1000
= 376/3.1 x 1/1000
= 0.121m3
➢ Volume of water,
= Weight of water/specific gravity of water x 1/1000
=1/169 x 1/1000
= 0.169m3
➢ Mass of chemical admixture @ ( admixture % by mass of Cementous material).
= Vol of chemical admixture/ specific gravity of admixture x 1/1000(Mass=1.2%by weight of
cement)
=3.76/1.18 x 1/100= 0.00318m3
➢ Weight of air in aggregate,
=((1-0.001)-(0.0.121+0.169+0.00318)
=0.6968m3
viii) Mass of coarse aggregate
=g x vol of fine aggregate x specific gravity of coarse aggregate x 1000
=0.696 x 0.63 x 2.58 x 1000

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=1131kg
ix) Mass of fine aggregate
= g x volume of fine aggregate x specific gravity of fine aggregate x 1000
=0.696 x 0.37 x 2.2 x 1000
=566.5kg
x) Mix proportions for trial number 1
Cement=376kg/m3
Water =169 kg/m3
Fine aggregate (SSD)=566.5 kg/m3
Coarse aggregate (SSD)=1131 kg/m3
Chemical admixture= 4.51 kg/m3
Free water-cement ratio =0.45
xi)Adjustment on water, fine aggregate and coarse aggregate;
➢ Fine aggregate (dry)
= Mass of fine aggregate in SSD condition/1+1/100
=566.5/1 + 1/100 = 560.89kg/m3
ᵙ561kg/m3
➢ Coarse Aggregate(Dry)
=Mass of coarse aggregate in SSD condition/1 + water absorption/100
=1131/1=0.5/100
=1125.37kg/m3
ᵙ1126kg/m3
Extra water absorption by coarse and fine aggregate,
➢ Coarse aggregate,
=Mass in SSD condition-Mass in dry state
=1131-1125.37
=5.63kg ᵙ 6kg
➢ Fine aggregate,
=566.5 - 561 = 5.5kg ᵙ 6kg
⸫Estimated water requirement becomes,
=169 + 5.5 + 6 =180.5kg/m3
xii) Mix proportion constituent after adjustment for dry aggregates,
Cement=376kg/m3

29
Water content to be added=180.5kg/m3
Fine aggregate (dry) =561kg/m3
Coarse aggregate (dry) =1126kg/m3
Chemical admixture=3.76kg/m3
Free water-cement ratio= 0.45
Table 6:Stipulation for proportioning
Grade Designation 53
Type of Cement OPC
Brand of Cement Ramco 53 Grade
Maximum nominal size of aggregate 20mm
Maximum cement content and maximum
water-cement ratio to be adopted and/or
exposure condition as per table 3 and table 5
of IS 456:2000
Moderate (RCC)
Workability 100mm
Method of Concrete placing Pumpable
Degree of site control Good
Type of aggregate Crushed angular
Maximum cement content not including fly
ash
450 kg per cubic meter
(Ref Clause no. 8.2 4.2 IS 456:2000
Chemical admixture type Super plasticizer

30
Table 7:Test data for material
Cement used OPC Ramco-53 grade
Plasticizer type Sikament
Specific Gravity of Cement 3.1
Specific gravity of 20mm Coarse aggerate [at
saturated surface dry (SSD) condition]
2.58
Specific gravity of Fine aggregate [at
saturated surface dry (SDD) condition]
2.2
Sieve analysis of Coarse Aggregate 8.37
Sieve analysis of Fine Aggregate 2.51
Sand Zone as per IS 383 II
Table 8: Mix proportioning formulation and important clauses
Characteristic strength at
28 days
30 MPa
Target average strength at
28 days
38.25 MPa Refer Table 1and 2, IS
10262:2019
Approximate air content 1.0%
Water cement ratio 0.45 Refer .Fig.1 10262:2019,Table
5 IS 456:2000
Water content per cubic
meter of concrete for
nominal maximum size of
20mm for aggregate for
50mm slump
181kg Refer Table.4, IS 10262:2019
Selection of water content 200kg Targeting 100mm slump
Note: As no super plasticizer is used no further reduction is done on the water content.
Cement Content 376kg per cubic meter Should be greater than 300kg
per cubic meter as per Table 5
of IS 456:2000
Note: For 20mm nominal maximum size of aggregate the
volume of coarse aggregate per unit volume of total
aggregate for Zone III is 0.64 when the water cement ratio
maintained at 0.50.
Refer Table 5, IS 10262:2019

31
Table 9:Mix Proportion for the first trial( After all the necessary adjustment)
Cement 376 kg per cubic meter
Fine aggregate 561 kg per cubic meter
Coarse aggregate (20mm) 563 kg per cubic meter
Water 181 kg per cubic meter
Admixture 3.76 kg per cubic meter
Mix type Weight Mix
Cement: Sand :Coarse Aggregate Mix Design
Water: Cement 0.45
Mixing Time 5 min
Table 10:Test Results
Overview: This trial did not achieve the target strength in 28 days due to excess water because
there was an increase in the water-cement ratio in the designing process and the slump was also
highly workable. However, we are coming with a mix design where for 1 hour mixing, we will get
adequate strength without any collapse shear. Hence, follow the new design for 1 hour mixing.
TEST RESULTS
Strength (MPa) of (150mm x 150mm x150mm) cube after Workability
7 days 14 days 28 days
collapse
slump
Cube sample 1 25.8 26 19.5
Cube sample 2 20.3 33 16.1
Cube sample 3 nil 26.1 11.7
Average 23.05 28.3 15.7

32
3.12 DESIGN CALCULATION OF M30 USING OPC WITH 1 HR MIXING
i)Strength of mix proportion,
fck = fck + 1.65 x S
=30 + 1.65 x 5
=38.25 N/mm2
Fck =fck + X
=30 + 6.5
=36.5 N/mm2
⸪38.25 N/mm2
For 20mm aggregate air content=10%(Table 3)
free water cement ratio is 0.45 for OPC 53 grade curve.
⸫ As per table 5 of IS 456:2000, the highest value of 0.45 is prescribed for severe exposure for
reinforced concrete.
The value will be attained greater than 0.45 in graph(fig 1) approximately as 0.48. Therefore, our
value is greater than 0.45 which the maximum prescribed.
⸫0.45 is taken
Water content =186kg (for 200mm slump) for 20mm aggregate.(By referring to table 4)
Calculated water content for 200mm slump.
=186 + 18 x 186/100= 219.48 kg ᵙ 220 kg
As admixtures (super plasticizers is used to reduce the water content). On the basis of data
obtained, the water content may be reduced . On the basis of trial data, the water content reduced
to 23% is considered by the use of super plasticizer at the rate of1% by weight of cement.

33
ᵙ 376kg/m3
)
Minimum cement content for severe exposure condition = 320kg/m3
(From table 5 of IS456:2000)
(and not exceed 450kg/m3
).
⸫ 376 kg > 320kg/m3
and 376 kg < 450kg/m3
hence, OK.
As per table 5 of IS 456:2000, the proportionate volume of coarse aggregate corresponding to 20
mm size aggregate and fine aggregate (Zone II) for water-cement ratio of 0.5=0.62
Water-cement ratio is 0.45.
Corrected volume of coarse aggregates for the water-cement ratio of 0.45 = 0.62+0.01 = 0.63.
vii) Mix volume calculation,
➢ Total volume = 1m3
➢ Entrapped air in wet concrete = 0.01m3
= Weight of cement / specific gravity of cement x 1/1000
= 376/3.1 x 1/1000
= 0.121m3
= mass of water/specific gravity of water x 1/1000
=1/169 x 1/1000
= 0.169m3
➢ Volume of chemical admixture @ ( admixture % by mass of Cementous material).
= vol of chemical admixture/ specific gravity of admixture x 1/1000(Mass=1.2%by weight of
cement)
=3.76/1.18 x 1/100= 0.00318m3
➢ Volume of air in aggregate,
=((1-0.001)-(0.0.121+0.169+0.00318)
=0.6968m3
viii) Mass of coarse aggregate
=g x volume of fine aggregate x specific gravity of coarse aggregate x 1000
=0.696 x 0.63 x 2.58 x 1000

34
=1131kg
ix) Mass of fine aggregate
=0.696 x 0.37 x 2.2 x 1000
=566.5kg
x) Mix proportions for trial number 1
Cement=376kg/m3
Water =169 kg/m3
Fine aggregate (SSD)=566.5 kg/m3
Free water-cement ratio=0.45
xi)Adjustment on water, fine aggregate and coarse aggregate;
➢ Fine aggregate (dry)
= Mass of fine aggregate in SSD condition/1+1/100
=566.5/1+1/100= 560.89kg/m3
ᵙ561kg/m3
➢ Coarse Aggregate(Dry)
=Mass of coarse aggregate in SSD condition/1+water absorption/100
=1131/1=0.5/100
=1125.37kg/m3
ᵙ1126kg/m3
Extra water to be added for absorption by coarse and fine aggregate,
➢ Coarse aggregate,
=Mass in SSD condition-Mass in dry state
=1131-1125.37
=5.63kg ᵙ6kg
➢ Fine aggregate,
=566.5-561=5.5kg ᵙ 6kg
⸫Estimated water requirement becomes,
=169+5.5+6=180.5kg/m3
xii) Mix proportion constituent after adjustment for dry aggregates,
Cement=376kg/m3

35
Water content to be added=180.5kg/m3
Fine aggregate (dry) =561kg/m3
Coarse aggregate (dry) =1126kg/m3
Chemical admixture=3.76kg/m3
Free water-cement ratio= 0.45
Type of Cement OPC
of IS 456:2000
Moderate (RCC)
Workability 100mm
ash
(Ref Clause no. 8.2 4.2 IS 456:2000

36
Plasticizer type Sikament
2.58
2.2
Sieve analysis of Fine Aggregate 2.51
Sand Zone as per IS 383 II
28 days
30 MPa
28 days
10262:2019
5 IS 456:2000
50mm slump
of IS 456:2000
maintained at 0.50.

37
Mix type Weight Mix
Water: Cement 0.45
Mixing Time 1 hour
Overview: Initially we have failed due to excess water but after 1 hour we are getting a good result.
However, for the target of achieving the strength while considering a quick hauling period, the 5
minute mixing trial performed below should get us the adequate strength without any collapse
shear. Hence, follow the new design for 5 minute mixing.
TEST RESULTS
110 mm
slump
Cube sample 1 23.9 20.2 40.8
Cube sample 2 20.9 19.4 28
Cube sample 3 21.4 20 40.1
Average 22.06 19.8 36.3

38
3.13 DESIGN CALCULATION OF M30 USING OPC WITH 5 MIN
MIXING
i) Strength of mix proportion,
fck= fck + 1.65 x S
=30 + 1.65 x 5
=38.25 N/mm2
Fck= fck + X
=30 + 6.5
=36.5 N/mm2
⸪ 38.25 N/mm2
For 20mm aggregate air content=10%(Table 3)
the free water ratio is 0.43 for OPC 53 grade curve.
⸫ As per table 5 of IS 456:2000 the highest value of 0.43 is prescribed for severe exposure for
reinforced concrete.
The value will be attained greater than 0.43 in graph(fig 1) approximately as 0.48. Therefore,
our value is greater than 0.43 which the maximum prescribed.
⸫0.43 is taken
Water content =186kg (for 100mm slump) for 20mm &10mm aggregate.(By referring to table
Required water content for 100mm slump.
=186 + 18 x 186/100= 219.48 kg ᵙ 220 kg.
As admixtures (super plasticizers is used to reduce the water content).On the basis of data
obtained, the water content may be reduced . On the basis of trial data, the water content reduced
to 23% is considered by the use of super plasticizer at the rate of1% by weight of cement.
ᵙ 394kg/m3
)

39
Minimum cement content for severe exposure condition,
= 320kg/m3
(From table 5 of IS 456: 2000)
⸫ 394kg > 320kg/m3
and 394 kg < 450kg/m3
hence, OK.
As per table 5 of IS 456:2000, the proportionate volume of coarse aggregate corresponding to
20 mm size aggregate and fine aggregate (Zone I) for water-cement ratio of 0.48=0.60
⸫ Water-cement ratio is 0.43.
Corrected volume of coarse aggregates for the water-cement ratio of 0.43 = 0.60+0.01 = 0.61.
➢ Mix proportion calculation,
Total volume = 1m3
zzEntrapped air in wet concrete = 0.01m3
= Weight of cement / specific gravity of cement x 1/1000
= 394/2.91 x 1/1000
= 0.135m3
= Weight of water/specific gravity of water x 1/1000
=1/169 x 1/1000
= 0.169m3
➢ Mass of chemical admixture @ ( admixture % by mass of Cementous material).
= Vol of chemical admixture/ specific gravity of admixture x 1/1000(Mass=1.2%by weight
of cement)
=3.76/1.18 x 1/100= 0.00318m3
➢ Weight of air in aggregate,
=((1-0.01)-(0.135+0.169+0.00318)
=0.682m3
vii) Mass of coarse aggregate
=g x volume of fine aggregate x specific gravity of coarse aggregate x 1000
=0.682 x 0.61 x 2.6 x 1000
=1082kg/m3

40
Type of Cement OPC
of IS 456:2000
Moderate (RCC)
Workability 100mm
ash
(Ref Clause no. 8.2 4.2 IS 456:2000
viii) Mass of fine aggregate
=0.69 x 0.37 x 2.2 x 1000
=639kg/m3
ix) Mix proportions for trial number 1
Cement=400kg/m3
Water =152 kg/m3
Fine aggregate (SSD)=639 kg/m3
Free water-cement ratio=0.38

41
Plasticizer type Fosroc Auramix (200)
2.6
2.4
Sieve analysis of Fine Aggregate 4
Sand Zone as per IS 383 I
28 days
30 MPa
28 days
10262:2019
5 IS 456:2000
50mm slump
of IS 456:2000
maintained at 0.50.

42
Mix type Weight Mix
Water: Cement 0.38
Mixing Time 5 min
Overview: In this trial, the targeted strength was achieved along with a true slump. Therefore, with
this result we can conclude by saying that M 30 grade of concrete can be used at construction
works which require longer hauling distance’s as well as for in-site casting works. The strength
obtained in both the second and the third trial have produced desired outputs for the strength and
the workability.
TEST RESULTS
110 mm
slump
Cube sample 1 21.2 42.9 39.2
Cube sample 2 22.2 30 41
Cube sample 3 22.6 38.6 32.4
Average 22 37.16 37.53

43
3.14 PROCEDURE OF SLUMP TEST FOR M30 GRADE CONCRETE
1. Firstly the inside surface of the mould should be cleaned thoroughly and proper greasing of
the surface should be performed.
2. Mould is placed on a smooth levelled surface.
3. The concrete is filled in mould each four different layers.
4. The concrete is subjected to 25 numbers of blows in each layers.
5. The excess concrete should be removed and the surface should be levelled with a trowel.
6. After the mould is compacted properly lift the mould in vertically upward direction which
caused the mould to subside.
7. Measure the slump value, four types of slumps can be achieved namely, True slump, Zero
slump, Collapse slump, Shear slump.
Slump for the given sample with 5 minutes of mixing time= 45mm (Collapse slump)and with
1 hour of mixing time=110mm (True slump).
Fig 12:Types of slump
3.15 PROCEDURE FOR M30 WITH 5 MINUTE OF MIXING TIME
1. Firstly the concrete mixer should be clean.
2. Weigh all the materials required.
3. Pour the coarse aggregates 10 mm and 20 mm in the concrete mixer.
4. Now add fine aggregate and cement in the concrete mixer.
5. Mix the materials in the dry condition in a mixer for a few seconds.

44
6. Now add the specified proportion of admixture in a water and put it into the concrete mixer.
7. Performed these steps within a duration of few minutes.
8. Mix it for a period of 5 minutes.
9. Check if the concrete is workable or not.
10. The initial slump has to be noted down.
11. The mixing process should be as fast as possible since continuous mixing will result in
production of heat and may lead to decrease in the slump of the concrete mix.
Requirement of workability.
The requirement of our slump as per our experiment is 100 mm at the site.
3.16 PROCEDURE FOR M30 WITH 1 HOUR OF MIXING TIME
1. Firstly the concrete mixer should be clean.
2. Weigh all the materials required.
3. Pour the coarse aggregates 10 mm and 20 mm in the concrete mixer.
4. Now add fine aggregate and cement in the concrete mixer.
5. Mix the materials in the dry condition in a mixer for a few seconds.
6. Now add the specified proportion of admixture in a water and put it into the concrete mixer.
7. Performed these steps within a duration of few minutes.
8. Mix it for continuously 1 hour.
9. Check the workability.
10. The initial slump has to be noted down.
11. The mixing process should be as fast as possible since continuous mixing will result in
production of heat and may lead to decrease in the slump of the concrete mix.
Requirement of workability- The requirement of the slump is 100 mm at the site.

45
3.17 CONCRETE CUBE CASTING PROCEDURE
1. The slump test is observed after mixing procedure and then after 1 hour the cubes shall be
casted.
2. The concrete shall be casted manually for better results and use of plate vibrator is less
preferable.
3. The casting process shall be performed thereafter.
4. The cubes will be cast in three-layers with each layer’s thickness as 50 mm approximately.
5. Each layer should be tamped using a tamping rod with about 35 to 45 blows.
6. The temperature of the lab should be preferably at 27 +/- 2-degree centigrade for casting the
cubes.
7. The cubes casted are done for nine cubes and then it is placed in a flat surface on the ground.
8. In order to prevent water evaporation from the cubes, cover them with a sheet.
9. Keep the cubes for 24 hours to harden and set.
10. The next day, open the cubes and also mark them individually for different purposes or of the
same.
11. Take the cubes and leave them for curing in a water table where the room temperature should
be in room temperature.
12. The compressive test of cubes will be performed on the cubes for 7, 14 and 28 days. Three
cubes shall be tested at each time frame.
13. After the seventh day, take out three cubes from the water tank.
14. Take the cubes to the CTM and dry it. The cubes should be surface saturated dry condition.
15. Start the machine and place each cube consecutively after each test.
16. Note that the weight of cubes is taken prior to the tests in the CTM.
17. Set-up the machine with the cubes and start the loading mechanism with loading of 2.5KN per
second.
18. After the testing is done, the cubes/debris is removed and the reading is noted of the peak stress
can also be calculated.
19. Perform the test for all three cubes.
20. Similarly, perform more tests on 14 days and 28 days.

46
Fig 13:Freshly casted cubes
Fig14:Cubes after test

47
CHAPTER
4
RESULT
The progress of our project so far has been done with OPC 53 grade cement on M 30 grade concrete
and found the target strength of 36.3N/mm2
in 28 days. Therefore, with this result we can
conclude by saying that M 30 grade of concrete can be used at construction works which require
longer hauling distance’s as well as for in-site casting works. The strength obtained in both the
second and the third trial have produced desired outputs for the strength and the workability of the
concrete.
Table 21:Test results for 1st
trial
TEST RESULT
Strength (MPa) of (150 mm x 150 mm x 150 mm) cube after Workability
collapse slump
Cube specimen 1 25.8 26 19.5
Cube specimen 3 nil 26.1 11.7
Average 23.05 28.3 15.7

48
Table 22:Test results for 2nd
trial
TEST RESULT
110 mm slump
Cube specimen 1 23.9 20.2 40.8
Cube specimen 2 20.9 19.4 28
Average 22.06 19.8 36.3
Table 23:Test results for 3rd
trial
TEST RESULT
100 mm slump
Average 22 37.16 37.53

49
CHAPTER
5
CONCLUSION
In our project the mix design for M 30 grade concrete was performed according to the IS code
method with varying mixing time. A number of tests were conducted along with the design,
thereafter nine cubes of dimension 150mm x 150mm x 150mm were used as moulds for the
concrete and they were tested in three trials. The compressive strength was tested in 7 days, 14
days and 28 days.
Accelerating admixtures were also used for gaining early strength of concrete and for quick setting.
The mixing time for each test was different, for the first trial it was 5 minutes, the second trial was
1 hour and for the last trial it was 5 minutes.
Therefore, it was observed that for tunnel construction works the hauling distance when minimum,
mixing of the concrete can be performed for 5 minutes. Whereas, if the distance between the
mixing plant and the site for placing is longer, the mixing of the concrete can be done for 1 hour.
It can be concluded that for large construction works, M 30 grade of concrete can be mixed and
used in site and for longer hauling distances.

50
REFERENCE
1. Chetan Isal, Swati Ambedkar; Study of various grade of concrete with and without admixture,
International journal for research in applied science and engineering technology, 2020.
2. Venu Malagavelli, Neelkanteswara Rao Paturu; strength and workability characteristics of
concrete by using different super plasticizer, International journal of materials engineering, 7-
11-2012.
3. Bureau of Indian Standards; Recommended guidelines for concrete mix design, IS:10262-2019
BIS, New Delhi, India, 2019.
4. Bureau of Indian Standards; Specification for coarse and fine aggregate from natural sources
for concrete, 2nd
revision, IS: 383-1970 BIS, New Delhi, 1970.
5. Bureau of Indian Standards; Method of test for strength of concrete, IS: 516-1959 BIS, New
Delhi, 1979.
6. Amar S. Deshmukh; Development of Mix Design for High Strength/Performance Concrete,
International journal of research in engineering science and technologies, Amravati, India,
December 2015.
7. Priya Harini; Strength and durability M30 concrete with various mineral and chemical
admixture, International Journal of Advances in Engineering & Technology, Bareilly, August
2015.
8. Ganesh Awchat, Laxmangauda Patil, Ashish More; Effect of different chemical admixtures on
fresh and hardened properties of M30 and M40 grade concrete, Advanced material research
1171, 105-120, 2022.

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