Curing is the name given to the procedure used for promoting the hydration of the cement and consist a control of temperature and moisture movement from the concrete. Curing allows continuous hydration of cement and consequently continuous gain in the strength, once curing stops strength gain of the concrete also stops. Proper moisture conditions are critical because the hydration of the cement virtually ceases when the relative humidity within the capillaries drops below 80%. Proper curing of concrete structures is important to meet performance and durability requirements. In conventional curing this is achieved by external curing applied after mixing, placing and finishing. Self-curing or internal curing is a technique that can be used to provide additional moisture in concrete for more effective hydration of cement and reduced self-desiccation. When concrete is exposed to the environment evaporation of water takes place and loss of moisture will reduce the initial water cement ratio which will result in the incomplete hydration of the cement and hence lowering the quality of the concrete.

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International Journal of Research and Innovation (IJRI)
International Journal of Research and Innovation (IJRI)
STUDY ON COMPARISON OF SELF CURING OF CONCRETE BY USING NORMAL
COARSE AGGREGATE AND RECYCLED COARSE AGGREGATE
Gajula Geetha1
, Damera Ramachander2
.
1 Research Scholar, Department of Civil Engineering, Aurora’s Technological and Research Institute, Hyderabad,India.
2 Associate professor , Department of Civil Engineering, Aurora’s Technological and Research Institute, Hyderabad,India.
*Corresponding Author:
Gajula Geetha,
Research Scholar, Department of Civil Engineering,
Aurora’s Technological and Research Institute,
Hyderabad India.
Published: April 22, 2016
Review Type: peer reviewed
Volume: III, Issue : II
Citation: Gajula Geetha, Research Scholar (2016) "STUDY
ON COMPARISON OF SELF CURING OF CONCRETE BY
USING NORMAL COARSE AGGREGATE AND RECYCLED
COARSE AGGREGATE"
INTRODUCTION
Curing
Curing is the process of controlling the rate and extent of
moisture transport from concrete during Cement hydra-
tion. It may be either after it has been placed in position
(or during the manufacture of concrete products), thereby
providing time for the hydration of the cement to occur.
Since the hydration of cement does take time in days,
and even weeks rather than hours curing must be under-
taken for a reasonable period of time, if the concrete is to
achieve its potential strength and durability. Curing may
also encompass the control of temperature since this af-
fects the rate at which cement hydrates. The curing peri-
od may depend on the properties required of the concrete,
the purpose for which it is to be used, and the ambient
conditions, i.e. the temperature and relative humidity of
the surrounding atmosphere. Curing is designed primar-
ily to keep the concrete moist, by preventing the loss of
moisture from the concrete during the period in which it
is gaining strength.
GENERAL
The experimental programme was planned as the follow-
ing.
Total 120 cubes, 120 cylinders, 120 prisms were cast
which involves different dosages (0%, 0.5%, 1% and 2%)
of self-curing agent PEG-6000 for four different mixes
(Mix A1,A2 and Mix B1,B2), under different curing condi-
tions (indoor, conventional). The compaction factor test
was conducted for all mixes to know the fresh property
of concrete. Compressive strength test was conducted at
7and 28 days of curing and to investigate the water re-
tentivity capacity the cubes were weighed for every three
days from the date of casting. The accuracy of the digital
weighing machine used is 5 gm. Strength graph is plotted
against percentage of self-curing agent; water retentivity
graph is plotted for average weight loss verses number of
days of curing.
FLOW CHART OF EXPERIMENTAL PROGRAMME FOR
CONCRETE
Abstract
Curing is the name given to the procedure used for promoting the hydration of the cement and consist a control of tem-
perature and moisture movement from the concrete. Curing allows continuous hydration of cement and consequently
continuous gain in the strength, once curing stops strength gain of the concrete also stops. Proper moisture conditions
are critical because the hydration of the cement virtually ceases when the relative humidity within the capillaries drops
below 80%. Proper curing of concrete structures is important to meet performance and durability requirements. In con-
ventional curing this is achieved by external curing applied after mixing, placing and finishing. Self-curing or internal
curing is a technique that can be used to provide additional moisture in concrete for more effective hydration of cement
and reduced self-desiccation. When concrete is exposed to the environment evaporation of water takes place and loss of
moisture will reduce the initial water cement ratio which will result in the incomplete hydration of the cement and hence
lowering the quality of the concrete.
An experimental study carried out an investigated the use of water-soluble polyethylene glycol (PEG 6000) as self-curing
agent. In this study compressive, tensile and flexural strength of self-curing concrete for 7 and 28 days and compared
the use of different coarse aggregate (i.e. M35, M45 of normal coarse aggregate and recycled aggregate) and found out
optimum strength.
1401-1402

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International Journal of Research and Innovation (IJRI)
FLOW CHART OF EXPERIMENTAL PROGRAMME FOR
CONCRETE
SPECIMENS MOULDED
Cube specimens:
Cube size: cube moulds of 150 x 150 x 150 mm size. Total
number of cubes casted: 96.
Cylinder specimens:
Cylinder size: cylinder moulds of 150 mm diameter x 300
mm length. Total number of cylinders casted: 96.
Prism specimens:
Prism size: prism moulds of 100 mm x 100 mm x 500 mm
size. Total number of prisms casted: 96.
Material quantity was shown in the table 3.3
TESTING OF SPECIMENS
After the specimen prepared for testing on universal
testing machine to find the Mechanical properties such
as compressive strength on cubes, flexural strength on
prisms, split tensile strength on cylinders.
Testing Procedure for Compressive Strength
The specimens were tested in accordance with IS
516:1969, the testing was done on universal compression
testing machine of 2000kN velocity. The machine has the
facility to control the rate of loading with a control valve.
The machine has been calibrated to the required stand-
ards. The platens are cleaned, oil level is checked and
kept ready in all respects for testing. As shown in the
plate 4 and 11.
RESULTS & DISCUSSION
As per Experimental programme results for different
experiments were obtained.
They are shown in table format or graph, which is to be
presented in this chapter.
STUDIES ON CONCRETE
COMPACTION FACTOR TEST
The compaction factor test is performed to calculate the
compaction factor, and to know more about workability.
The test results are shown in table 4.1. The plot of the
compaction factor and different dosage of PEG 6000 is
shown in Figure.
The following are the observations on Compaction factor
test.
i) In case of specimens with PEG 6000 of Mix A it is clear
that compaction factor for 0.5% dosage of self curing
agent is less when compared to other dosages 1% and 2%.
ii) In case of specimens with PEG 6000 of Mix B 1% dos-
age compaction factor is more compared to other dosages
(1% and 2%).
iii) It is also clear that compaction factor is more for Mix B
in 1% and 2% when compared to Mix A.
iv) It is also observed that in Mix A the compaction factor
is increased with increase of % of PEG 6000. But in Mix B
it is increased from 0.5% to 1% and then it is decreased.
Water Retentivity Test
Water Retentivity Test Results for Mix A1
Concrete with high molecular weight PEG subjected to
indoor curing was studied by weighing the samples at
regular intervals of 3 days, with digital weighing machine
of accuracy 5gms up to 28 days.The results were recorded
in table 4.2.The analysis of results or average weight loss
of individual specimen is shown in table 4.3.The average
weight loss is shown in fig.4.2. The following are the ob-
servations on water retentivity of concrete.
i) It is clear that 0% dosage of self curing agent is losing
more weight when compared to other dosages (0.5%, 1%
and 2% of self curing agent).
ii) It is also observed that 2% dosage of self curing agent
shows lower weight loss when compared to other dosages
(0%, .5% and 1% of self curing agent).
Water Retentivity Test Results for Mix A2
Concrete with high molecular weight PEG subjected to
indoor curing was studied by weighing the samples at
regular intervals of 3 days, with digital weighing machine
of accuracy 5 gm up to 28 days. The results were recorded
in table 4.4. The analysis of results or average weight loss
of individual specimen is shown in table 4.5.The average
weight loss is shown in fig.4.3. The following are the ob-
servations on water retentivity of concrete.
(i) It is clear that 0% dosage of self curing agent is losing
more weight when compared to other dosages (0.5%, 1%
and 2% of self curing agent).
(ii)It is also observed that 1% dosage of self curing agent
shows lower weight loss when compared to other dosages
(0%, .5% and 2% of self curing agent)
Water Retentivity Test Results for Mix B 1
Concrete with high molecular weight PEG subjected to in-
door curing was studied by weighing the samples at regu-
lar intervals of 3 days, with digital weighing machine of
accuracy 5 gm up to 28 days. The results were recorded in
table 4.6. The average weight loss is shown in fig.5.6.The
analysis of results or percentage weight loss of individual
specimen are shown in table 4.7. The following are the
observation on water retentivity of concrete.
i.It is clear that conventional concrete with indoor curing
is losing more weight when compared to other dosages
0.5%, 1% and 2% of self curing agent.

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International Journal of Research and Innovation (IJRI)
ii.It is also clear that 2 % dosage of S.C.A result is almost
nearer when compared to the dosages of conventional
concrete with indoor curing. But it is not appreciable
when compared with 0.5%.
iii.It is also observed that 2 % dosage of S.C.A shows less
weight loss when compared to other dosages.
Water Retentivity Test Results for Mix B 2
Concrete with high molecular weight PEG subjected to
indoor curing was studied by weighing the samples at
regular intervals of 3 days, with digital weighing machine
of accuracy 5 gm up to 28 days. The results were recorded
in table 4.8.The average weight loss is shown in fig4.5.The
analysis of results or percentage weight loss of individual
specimen are shown in table 4.9. The following are the
observation on water retentivity of concrete.
(i) It is clear that conventional concrete with indoor curing
is losing more weight when compared to other dosages
0.5%, 1% and 2% of self curing agent.
(ii) It is also clear that 1 % dosage of S.C.A result is al-
most nearer when compared to the dosages of conven-
tional concrete with indoor curing. But it is not appreci-
able when compared with 2%.
(iii)It is also observed that 1% dosage of S.C.A shows less
weight loss when compared to other dosages.
TESTING OF SPECIMENS
Compressive Strength Results for Mix A1
The compressive strength test was conducted at 7 and 28
days of age for conventional concrete with wet and indoor
curing and also for concrete with different dosages (0.5%,
1% and 2%) of self curing agent.
i) The compressive strength of 2% of S.C.A is more when
compare to other dosages upto 14 days.
ii) The strength of the conventional concrete specimen with
indoor curing also showed better compressive strength
when compared to 0.5% and 1% of S.C.A at 28days.
iii) The specimen with 2% dosage shown better perfor-
mance when compared to specimen with 0.5% and 2% of
SCA and also conventional concrete at 28days.
iv) The compressive strength of 2% of S.C.A of indoor cur-
ing is equal to conventional concrete of wet curing at 14
and 28 days.
v) The strength of the specimen in which S.C.A of different
dosages other than 0.5% are shown better compressive
strength when compared to conventional concrete of wet
curing.
vi) 1% of S.C.A has shown better strength than conven-
tional concrete with wet and indoor curing at early age i.e.
upto 7days but not as good as 2%.
vii) 2% S.C.A shown better strength at 28 days & 1% has
shown better performance at 7 days in case of indoor cur-
ing.
viii) The compressive strength is more for 0%, 2% and 1%
of S.C.A and also conventional concrete in indoor curing
when compared to conventional concrete in wet curing.
ix) 0.5% S.C.A has shown less compressive strength when
compared to other wet and indoor curing.
Split tensile Strength Results for Mix A1
The split tensile strength test was conducted at 7 and 28
days of age for conventional concrete with wet and indoor
curing and also for concrete with different dosages (0.5%,
1% and 2%) of self curing agent.
i) The split tensile strength of 2% of S.C.A is more when
compare to other dosages upto 28 days.
ii) The strength of the conventional concrete specimen
with indoor curing also showed better split tensile strength
when compared to 0.5% and 1% of S.C.A at 28days.
iii) The specimen with 2% dosage shown better perfor-
mance when compared to specimen with 0.5% and 2% of
SCA and also conventional concrete at 28days.
iv) The split tensile strength of 2% of S.C.A of indoor cur-
ing is equal to conventional concrete of wet curing at 14
and 28 days.
v) The strength of the specimen in which S.C.A of differ-
ent dosages other than 0.5% are shown better split tensile
strength when compared to conventional concrete of wet
curing.
vi) 1% of S.C.A has shown better strength than conven-
tional concrete with wet and indoor curing at early age i.e.
upto 7days but not as good as 2%.
vii) 2% S.C.A shown better strength at 28 days & 1% has
shown better performance at 7 days in case of indoor cur-
ing.
viii) The split tensile strength is more for 0%, 2% and 1%
of S.C.A and also conventional concrete in indoor curing
when compared to conventional concrete in wet curing.
ix) 0.5% S.C.A has shown less split tensile strength when
compared to other wet and indoor curing.
Flexural Strength Results for Mix A1
The flexural strength test was conducted at 7 and 28 days
of age for conventional concrete with wet and indoor cur-
ing and also for concrete with different dosages (0.5%, 1%
and 2%) of self curing agent.
i) The flexural strength of 2% of S.C.A is more when com-
pare to other dosages upto 28days.
ii) The strength of the conventional concrete specimen
with indoor curing also showed better flexural strength
when compared to 0.5% and 1% of S.C.A at 28days.
iii) The specimen with 2% dosage shown better perfor-
mance when compared to specimen with 0.5% and 2% of
SCA and also conventional concrete at 28days.
iv) The flexural strength of 2% of S.C.A of indoor curing
is equal to conventional concrete of wet curing at 14 and
28 days.
v) The strength of the specimen in which S.C.A of differ-
ent dosages other than 0.5% are shown better flexural
strength when compared to conventional concrete of wet
curing.
vi) 1% of S.C.A has shown better strength than conven-
tional concrete with wet and indoor curing at early age i.e.
upto 7days but not as good as 2%.
vii) 2% S.C.A shown better strength at 28 days & 1% has
shown better performance at 7 days in case of indoor cur-
ing.
viii) The flexural strength is more for 0%, 2% and 1% of
S.C.A and also conventional concrete in indoor curing
when compared to conventional concrete in wet curing.
ix) 0.5% S.C.A has shown less flexural strength when
compared to other wet and indoor curing.
Compressive Strength Results for Mix A2
The compressive strength test was conducted at 7 and 28
days of age for conventional concrete with wet and indoor
curing and also for concrete with different dosages (0.5%,
1% and 2%) of self curing agent.

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International Journal of Research and Innovation (IJRI)
i. The compressive strength of 2% of S.C.A is more when
compare to other dosages upto 28 days.
ii. The strength of the conventional concrete specimen with
indoor curing also showed better compressive strength
when compared to 1% and 0.5% of S.C.A at 28days.
iii. The specimen with 2% dosage shown better perfor-
mance when compared to specimen with 0.5% and 1% of
SCA and also conventional concrete at 28days.
iv. The compressive strength of 2% of S.C.A of indoor cur-
ing is equal to conventional concrete of wet curing at 28
days.
v. The strength of the specimen in which S.C.A of different
dosages other than 0.5% are shown better compressive
strength when compared to conventional concrete of wet
curing.
vi. 2% of S.C.A has shown better strength than conven-
tional concrete with wet and indoor curing at early age i.e.
upto 7days but not as good as 1%.
vii. 2% S.C.A shown better strength at 28 days & 1% has
shown better performance at 7days in case of indoor cur-
ing.
viii. The compressive strength is more for 1% and 2% of
S.C.A and also conventional concrete in indoor curing
when compared to conventional concrete in wet curing.
0.5% S.C.A has shown less compressive strength when
compared to other wet and indoor curing.
Split tensile Strength Results for Mix A2
The split tensile strength test was conducted at 7 and 28
days of age for conventional concrete with wet and indoor
curing and also for concrete with different dosages (0.5%,
1% and 2%) of self curing agent.
i. The split tensile strength of 2% of S.C.A is more when
compare to other dosages upto 14 days.
ii. The strength of the conventional concrete specimen
with indoor curing also showed better split tensile strength
when compared to 0.5% and 1% of S.C.A at 28days.
iii. The specimen with 2% dosage shown better perfor-
mance when compared to specimen with 0.5% and 1% of
SCA and also conventional concrete at 28days.
iv. The split tensile strength of 2% of S.C.A of indoor cur-
ing is equal to conventional concrete of wet curing at 14
and 28 days.
v. The strength of the specimen in which S.C.A of differ-
ent dosages other than 2% are shown better split tensile
strength when compared to conventional concrete of wet
curing.
vi. 1% of S.C.A has shown better strength than conven-
tional concrete with wet and indoor curing at early age i.e.
upto 7days but not as good as 2%.
vii. 2% S.C.A shown better strength at 28 days & 1% has
shown better performance at 7 days in case of indoor cur-
ing.
viii.The split tensile strength is more for 0%, 2% and 1%
of S.C.A and also conventional concrete in indoor curing
when compared to conventional concrete in wet curing.
ix. 0.5% S.C.A has shown less split tensile strength when
compared to other wet and indoor curing.
Flexural Strength Results for Mix A2
The flexural strength test was conducted at 7 and 28 days
of age for conventional concrete with wet and indoor cur-
ing and also for concrete with different dosages (0.5%, 1%
and 2%) of self curing agent.
x. The flexural strength of 2% of S.C.A is more when com-
pare to other dosages upto 28 days.
xi. The strength of the conventional concrete specimen
with indoor curing also showed better flexural strength
when compared to 0.5% and 1% of S.C.A at 28days.
xii. The specimen with 2% dosage shown better perfor-
mance when compared to specimen with 0.5% and 2% of
SCA and also conventional concrete at 28days.
xiii. The flexural strength of 2% of S.C.A of indoor curing
is equal to conventional concrete of wet curing at 14 and
28 days.
xiv. The strength of the specimen in which S.C.A of dif-
ferent dosages other than 0.5% are shown better flexural
strength when compared to conventional concrete of wet
curing.
xv. 1% of S.C.A has shown better strength than conven-
tional concrete with wet and indoor curing at early age i.e.
upto 7days but not as good as 2%.
xvi. 2% S.C.A shown better strength at 28 days & 1%
has shown better performance at 7 days in case of indoor
curing.
xvii. The flexural strength is more for 0%, 2% and 1%
of S.C.A and also conventional concrete in indoor curing
when compared to conventional concrete in wet curing.
xviii. 0.5% S.C.A has shown less flexural strength when
compared to other wet and indoor curing.
Compressive Strength Result for Mix B1
The compressive strength test was conducted at 7 and 28
days of age for conventional concrete with wet and indoor
curing and also for concrete with different dosages (0.5%,
1% and 2%) of self curing agent.
i.The compressive strength of specimen with conventional
concrete is more for both wet and indoor curing when
compare to other dosages.
ii. The strength of the specimen in which S.C.A of differ-
ent dosages (0.5% and 2%) are shown less compressive
strength when compare to 1% of S.C.A.
iii. The compressive strength of specimen with 1% PEG is
nearly equal to 2% PEG.
iv. The compressive strength of conventional concrete of
wet curing is more when compare to other dosages of in-
door curing.
v. Conventional concrete has shown better strength in
both indoor & wet curing than other specimens having
SCA with different dosages.
vi. Mix B with PEG is not shown better results when com-
pare to Mix A with PEG.
Split tensile Strength Result for Mix B1
The Split tensile strength test was conducted at 7 and 28
days of age for conventional concrete with wet and indoor
curing and also for concrete with different dosages (0.5%,
1% and 2%) of self curing agent.
vii. The split tensile strength of specimen with conven-
tional concrete is more for both wet and indoor curing
when compare to other dosages.
viii. The strength of the specimen in which S.C.A of differ-
ent dosages (0.5% and 2%) are shown less tensile strength
when compare to 1% of S.C.A.
ix. The split tensile strength of specimen with 1% PEG is
nearly equal to 2% PEG.
x. The tensile strength of conventional concrete of wet
curing is more when compare to other dosages of indoor
curing.
xi.Conventional concrete has shown better strength in
both indoor & wet curing than other specimens having
SCA with different dosages.

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International Journal of Research and Innovation (IJRI)
xii. Mix B with PEG is not shown better results when com-
pare to Mix A with PEG.
flexural Strength Result for Mix B1
The flexural strength test was conducted at 7 and 28 days
of age for conventional concrete with wet and indoor cur-
ing and also for concrete with different dosages (0.5%, 1%
and 2%) of self curing agent.
i. The flexural strength of specimen with conventional
concrete is more for both wet and indoor curing when
compare to other dosages.
ii. The strength of the specimen in which S.C.A of different
dosages (0.5% and 2%) are shown less flexural strength
when compare to 1% of S.C.A.
iii. The flexural strength of specimen with 1% PEG is
nearly equal to 2% PEG.
iv. The flexural strength of conventional concrete of wet
curing is more when compare to other dosages of indoor
curing.
v. Conventional concrete has shown better strength in
both indoor & wet curing than other specimens having
SCA with different dosages.
vi. Mix B with PEG is not shown better results when com-
pare to Mix A with PEG.
Compressive Strength Result for Mix B2
The compressive strength test was conducted at 7 and 28
days of age for conventional concrete with wet and indoor
curing and also for concrete with different dosages (0.5%,
1% and 2%) of self-curing agent.
i. The compressive strength of specimen with convention-
al concrete is more for both wet and indoor curing when
compare to other dosages.
ii. The strength of the specimen in which S.C.A of differ-
ent dosages (0.5% and 2% ) are shown less compressive
strength when compare to 1% of S.C.A.
iii. The compressive strength of specimen with 1% PEG is
nearly equal to 2% PEG.
iv. The compressive strength of conventional concrete of
wet curing is more when compare to other dosages of in-
door curing.
v. Conventional concrete has shown better strength in
both indoor & wet curing than other specimens having
SCA with different dosages.
vi. Mix B with PEG is not shown better results when com-
pare to Mix A with PEG
Comparison of Mix A2 and Mix B2
• The compressive strength is more for Mix A2 at 7 and 28
days when compared to Mix B2.
• The compressive strength is more for Mix A at 2% of SCA
and it is very low at same 0.5% of SCA for Mix B at 7 days.
• The compressive strength is nearly same for 0% and
0.5% of SCA for Mix B2 at 7 days.
• The compressive strength is nearly same for Mix B2 at
28 days for 0% and 0.5% of SCA.
• The compressive strength is more for 2% of SCA for Mix
A2 at 28 days of age.
• The compressive strength is more for 1% of SCA for Mix
B2 at 28 days of age.
• The split tensile strength is more for Mix A2 at 7 and 28
days when compared to Mix B2.
• The split tensile strength is more for Mix A at 2% of SCA
and it is very low at same 0.5% of SCA for Mix B at 7 days.
• The split tensile strength is nearly same for 0% and
0.5% of SCA for Mix B2 at 7 days.
• The split tensile strength is nearly same for Mix B2 at 28
days for 0% and 0.5% of SCA.
• The split tensile strength is more for 2% of SCA for Mix
A2 at 28 days of age.
• The split tensile strength is more for 1% of SCA for Mix
B2 at 28 days of age.
• The flexural strength is more for Mix A2 at 7 and 28
days when compared to Mix B2.
• The flexural strength is more for Mix A at 2% of SCA and
it is very low at same 0.5% of SCA for Mix B at 7 days.
• The flexural strength is nearly same for 0% and 0.5% of
SCA for Mix B2 at 7 days.
• The flexural strength is nearly same for Mix B2 at 28
days for 0% and 0.5% of SCA.
• The split tensile strength is more for 2% of SCA for Mix
A at 28 days of age
• The split tensile strength is more for 1% of SCA for Mix
B2 at 28 days of age
Compaction factor for different percentages of PEG 6000
Avg Weight Loss for Mix A2 (CUBES) For the Different Dosages
of PEG 6000
Avg Weight Loss for Mix A2 (CYLINDERS) For the Different Dos-
ages of PEG 6000

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International Journal of Research and Innovation (IJRI)
Avg Weight Loss for Mix A2(PRISMS) For the Different Dosages
of PEG 6000
Avg Weight Loss for Mix B1 (CUBES) For the Different Dosages
of PEG 6000
Variation of 28 days compressive strength with different dosages
of PEG6000
Variation of 7 days split tensile strength with different dosages
of PEG6000
Variation of 28 days split tensile strength with different dosages
of PEG6000
CONCLUSIONS& SCOPE FOR FUTURE STUDIES
General
After the analysis of the result of the experimental pro-
gramme the following conclusions were arrived for self
curing agent polyethylene glycol (PEG6000) and compari-
son of different aggregates are obtained.
Conclusions
a) Due to the use of PEG6000
• The workability of concrete with low w/c ratio has signif-
icant effect due to higher molecular weight polyethylene
glycol (PEG6000).
• Water retention of the concrete with low w/c ratio in
conjunction has significant effect due to addition of high-
er molecular weight polyethylene glycol (PEG6000).
• The compressive strength of concrete with lower w/c ra-
tio and with lower dosage of polyethylene glycol (PEG6000)
is beneficial.
• The use of higher molecular weight polyethylene glycol
(PEG6000) with higher w/c ratio is not beneficial.
b)Conclusions from comparative studies of different
coarse aggregate
• Effectiveness of self-curing concrete is affected by w/c
ratio and percentage dosages of self-curing agent.
• Water retention of concrete mixes incorporating self-
curing agent is higher compared to conventional concrete
mixes.
• The compressive strength of concrete with low w/c ratio
has significant effect due to change in curing regime.
• The mix which shows lower weight loss need not give
higher compressive strength.
• Water retention of concrete with lower w/c ratio in-
corporating higher molecular weight polyethylene glycol
(PEG 6000) with lower dosage is more beneficial.
c)Due to the use of Normal coarse aggregate
Workability of concrete has increased due to PEG 6000
when compared to conventional concrete.
Water retention of the concrete with low w/c ratio in con-
junction has significant effect due to addition of higher
molecular weight polyethylene glycol (PEG6000).
Compressive strength increases from 0.5% to 2% the in-
creases in strength at 2% is maximum then of conven-
tional concrete in both the grades (M35, M45).split tensile
strength increased from 0.5% to 2% at 2% is greater then
of conventional concrete in both the grades.
Flexural strength increased from 0.5% to 2%. The in-
creases in strength at 2% is maximumof conventional
concrete in both the grades .
d)Due to the use of Recycled coarse aggregate
Workability of concrete has increased due to PEG 6000
when compared to conventional concrete.
Compressive strength increases from 0.5% to 1% and
then decreases at 2% the increases in strength at 1%
is maximum then of conventional concrete in both the
grades (M35, M45).
split tensile strength increased from 0.5% to 1% and then
decrease at 2% the increase in strength at 1% is maxi-
mum greater then of conventional concrete in both the
grades.

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International Journal of Research and Innovation (IJRI)
Flexural strength increased from 0.5% to 1%. The in-
creases in strength at 1% is maximum of conventional
concrete in both the grades.
The strength is more for normal coarse aggregate com-
pared to recycled coarse aggregate.
EXPERIMENTAL IMAGES
Specimens after casting
Compression Testing Machine of Capacity 2000 KN
Flexural test for prism A2
Compressive test for cube A1
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8. 251
International Journal of Research and Innovation (IJRI)
Author
Gajula Geetha,
Research Scholar,
Department of Civil Engineering,
Aurora’s Technological and Research Institute,
Hyderabad,India.
Damera Ramachander,
Associate professor,
Department of Civil Engineering,
Aurora’s Technological and Research Institute,
Hyderabad,India.