1 COMPARSION OF COMPRESSION STRENGTH OF CONVENTIONAL CONCRETE WITH SELF-CURING CONCRETE BY USING POLYETHYLENE GLYCOL Anish C 1 , Thendral S 2 Assistant Professor 1,2 ,Department of Civil Engineering 1,2 BIST, BIHER, Bharath University [email protected]. ABSTRACT A self-curing concrete is given to retain water from air to accomplish better hydration of bond in solid which takes care of the issue of brought down bond hydration in light of disgraceful curing, and in this manner unsuitable properties of cement. The present examination includes the utilization of self-curing specialist viz., polyethylene glycol (PEG) of sub-atomic weights (PEG 400) for measurements extending between 1% 2% and 3% by weight of concrete added to blending water.Near investigations were completed for water retentively, compressive quality following 28 days for ordinary cured and self-cured cement. The properties of self-cured cement are at any rate tantamount to and at some point superior to those of cement with customary curing. INTRODUCTION CURING Curing of concrete is maintaining satisfactory moisture content in concrete during its early stages in order to develop the desired properties. However, good curing is not always practical in many cases[1-7]. Several investigators explored the possibility of accomplishing self- curing concrete. Therefore, the need to develop self-curing agents attracted several researchers. SELF CURING The concept of self-curing agents is to reduce the water evaporation from concrete, and hence increase the water retention capacity of the concrete compared to conventional concrete . It was found that water soluble polymers can be used as self-curing agents in concrete. Concrete incorporating self-curing agents will represent a new trend in the concrete construction in the new millennium[8-14]. Curing of concrete plays a major role in developing the concrete microstructure and pore structure, and hence improves its durability and performance. The concept of self-curing agents is to reduce the water evaporation from concrete, and hence increase the water retention capacity of the concrete compared to conventional concrete. The use of self-curing admixtures is very important from the point of view that water resources are getting valuable every day (i.e., each 1cu.m of concrete requires about 3cu.m of water for construction most of which is for curing). International Journal of Pure and Applied Mathematics Volume 119 No. 12 2018, 8421-8438 ISSN: 1314-3395 (on-line version) url: http://www.ijpam.eu Special Issue ijpam.eu 8421
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COMPARSION OF COMPRESSION ST RENGTH OF … · 1 COMPARSION OF COMPRESSION ST RENGTH OF CONVENTIONAL CONCRETE WITH SELF -CURING CONCRETE BY USING POLYETHYLENE GLYCOL Anish C 1, Thendral
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1
COMPARSION OF COMPRESSION STRENGTH OF CONVENTIONAL CONCRETE
WITH SELF-CURING CONCRETE BY USING POLYETHYLENE GLYCOL
A self-curing concrete is given to retain water from air to accomplish better hydration of bond in
solid which takes care of the issue of brought down bond hydration in light of disgraceful curing,
and in this manner unsuitable properties of cement. The present examination includes the
utilization of self-curing specialist viz., polyethylene glycol (PEG) of sub-atomic weights (PEG
400) for measurements extending between 1% 2% and 3% by weight of concrete added to
blending water.Near investigations were completed for water retentively, compressive quality
following 28 days for ordinary cured and self-cured cement. The properties of self-cured cement
are at any rate tantamount to and at some point superior to those of cement with customary
curing.
INTRODUCTION
CURING
Curing of concrete is maintaining satisfactory moisture content in concrete during its
early stages in order to develop the desired properties. However, good curing is not always
practical in many cases[1-7]. Several investigators explored the possibility of accomplishing self-
curing concrete. Therefore, the need to develop self-curing agents attracted several researchers.
SELF CURING
The concept of self-curing agents is to reduce the water evaporation from concrete, and
hence increase the water retention capacity of the concrete compared to conventional concrete. It
was found that water soluble polymers can be used as self-curing agents in concrete. Concrete
incorporating self-curing agents will represent a new trend in the concrete construction in the
new millennium[8-14].
Curing of concrete plays a major role in developing the concrete microstructure and pore
structure, and hence improves its durability and performance. The concept of self-curing agents
is to reduce the water evaporation from concrete, and hence increase the water retention capacity
of the concrete compared to conventional concrete. The use of self-curing admixtures is very
important from the point of view that water resources are getting valuable every day (i.e., each
1cu.m of concrete requires about 3cu.m of water for construction most of which is for curing).
International Journal of Pure and Applied MathematicsVolume 119 No. 12 2018, 8421-8438ISSN: 1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue ijpam.eu
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Excessive evaporation of water (internal or external) from fresh concrete should be
avoided; otherwise, the degree of cement hydration would get lowered and thereby concrete may
develop unsatisfactory properties. Curing operations should ensure that adequate amount of
water is available for cement hydration to occur[15-19].
This investigation discusses different aspects of achieving optimum cure of concrete
without the need for applying external curing methods. The effect of curing, particularly new
techniques such as "self-curing", on the properties of high performance concrete is of primary
importance to the modern concrete industry.
MECHANISM OF SELF CURING
The mechanism of self-curing can be explained as follows:
Continuous evaporation of moisture takes place from an exposed surface due to the
difference in chemical potentials (free energy) between the vapor and liquid phases.
The polymers added in the mix mainly form hydrogen bonds with water molecules and
reduce the chemical potential of the molecules which in turn reduces the vapor pressure
which reduces the rate of evaporation from the surface.
OBJECTIVES
In this study the compressive strength of concrete containing self-curing agent is
investigated and compared with conventional curing. Concrete strength with the age of concrete
was carried out in order to evaluate the compressive strength for different dosages of self-curing
agent and for different conditions[20-26].
The objective of the paper is to study the effect of polyethylene glycol (PEG 400) on
strength characteristics of Self-curing concrete. The objective is to study the mechanical
characteristic of concrete i.e., compressive strength by varying the percentage of PEG from 1%
to 3% by weight of cement for both M20 grade of concrete[27-35]. The objective is study the
mechanical characteristics of concrete such as compressive strength, by varying the percentage
of PEG from 1% to 3% by weight of cement for M20 grades of concrete.
International Journal of Pure and Applied Mathematics Special Issue
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METHODOLOGY
Fig 1: Flow chart of the method followed
COLLECTION OF
REQUIRED MATERIALS
TESTING OF
PROPERTIES OF
MATERIALS
MIX DESIGN OF
CONCRETE
CASTING OF CUBES
1. CONVENTIONAL CONCERTE
2. SELF CURING CONCRETE (PEG-400)
11111%, 2%, 3%
REGULAR MONITORING OF
COMPRESSIVE STRENGTH
FOR 7, 14, 28 DAYS
COMPARING THE COMPRESSIVE
STRENGTH OF S.C.C.WITH
CONVENTINAL CONCRTE
STRENGTH
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POLYETHYLENE GLYCOL (PEG)
Polyethylene glycol is a condensation polymers of ethylene oxide and water with the general
formula H (OCH2CH2) nOH, where n is the average number of repeating ox ethylene groups
typically from 4 to about 180. The low molecular weight members from n=2 to n=4 are
diethylene glycol, triethylene glycol and tetraethylene glycol respectively, which are produced as
pure compounds. The low molecular weight compounds up to 700 are colourless, odourless
viscous liquids with a freezing point from 10 C (diethylene glycols), while polymerized
compounds with higher molecular weight than 1,000 are wax like solids with melting point up to
67 C for n 180. The abbreviation (PEG) is termed in combination with a numeric suffix which
indicates the average molecular weights. One common feature of PEG appears to be water-
soluble. The specification of PEG400.It is soluble also in many organic solvents including
aromatic hydrocarbons (not aliphatic). They are used to make emulsifying agents and
detergents, and as plasticizers, humectants, and water-soluble textile lubricants. The wide range
of chain lengths provides identical physical and chemical properties for the proper application
selections directly or indirectly in the field of;
Alkyd and polyester resin preparation to enhance water dispensability and water-based
coatings.
Ant dusting agent in agricultural formulations
Brightening effect and adhesion enhance in electroplating and electroplating process.
Cleaners, detergents and soaps with low volatility and low toxicity solvent properties.
Coupling agent, humectants, solvent and lubricant in cosmetics and personal care bases.
Dimensional stabilizer in wood working operations
Dye carrier in paints and inks
Heat transfer fluid formulation and defoamer formulations.
Low volatile, water soluble and noncorrosive lubricant without staining residue in food and
package process.
Paper coating for ant sticking, colour stabilizing, good gloss.
Plasticizer to increase lubricity and to impart a humectants property in ceramic mass,
adhesives and binders.
Softener and antistatic agent for textiles
Soldering fluxes with good spreading property.
Polyethylene glycol is non-toxic, odourless, neutral, lubricating, non-volatile and no irritating
and is used in a variety of pharmaceuticals and in medications as a solvent, dispensing agent,
ointment and suppository bases[36-41], vehicle, and tablet excipient. Chemical structure of PEG
shown below.
International Journal of Pure and Applied Mathematics Special Issue
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Polyethylene glycol is produced by the interaction of ethylene oxide with water, ethylene
glycol or ethylene glycol oligomers.
Test data for design
Concrete compressive strength required in the field @ 28 days= 20N/𝑚𝑚2
Maximum size of aggregate = 20mm
Degree of Workability = 0.90 (C.F)
Degree of quality control = Good
Type of Exposure = Mild
Specific Gravity of cement = 3.15
Specific gravity of coarse aggregate = 2.81
Specific gravity of fine aggregate = 2.59
Water absorption
Coarse aggregate = 0.50%
Fine aggregate = 1.00%
Free moisture
Coarse aggregate = Nil
Fine aggregate = 2%
Design Calculation
a) for conventional concrete
M20 = 1:1.5:3:0.5
Volume = 1+1.5+3 = 5.5
Selection of Coarse aggregate
20mm aggregate is taken as per the analysis from IS 10262
Total volume ingredients for using = 1.57
Selection for Fine aggregate
Air content for 20mm aggregate = 2% by volume of concrete
Selection of w/c ratio
W/c is taken from IS 10262 = 0.5
International Journal of Pure and Applied Mathematics Special Issue
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Max. W/c ratio As per IS 456-2000 = 0.6
Calculation
Volume of broken stone required = (3/5.5) x 1.57 = 0.856 𝑚3
Volume of sand required = (1.5/5.5) x 1.57 = 0.471 𝑚3
Volume of cement = (1/5.5) x 1.57 = 0.285 𝑚3
=0.285 x 1440 = 441Kg
For 1 𝑚3 of M20 (1:1.5:3)
Broken stone = 0.856 𝑚3
Sand = 0.472 𝑚3
Cement = 8.22 Kg
Table 1: MIX RATIO OF CONVENTIONAL CONCRETE M20
SL.N
O
NO OF
CUBES
(7DAY
S)
NO
OF
CUBE
S
(14
DAYS
)
NO
OF
CUBE
S (28
DAYS
)
TOTA
L NO
CUBE
S
CEMEN
T
OPC(Kg
s)
FINE
AGGREGA
TE
(Kgs)
COARSE
AGGREGA
TE
(Kgs)
WATE
R
(Lts)
1 3 3 3 9 17.65 29.6 37.6 6.3
2 3 3 3 9 17.65 29.6 37.6 6.3
3 3 3 3 9 17.65 29.6 37.6 6.3
b) for self-curing concrete
M20 = 1:1.5:3:0.5
Volume = 1+1.5+3 = 5.5
Selection of Coarse aggregate
20mm aggregate is taken as per the analysis from IS 10262
Total volume ingredients for using = 1.57
International Journal of Pure and Applied Mathematics Special Issue
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Selection for Fine aggregate
Air content for 20mm aggregate = 2% by volume of concrete
Selection of w/c ratio
W/c is taken from IS 10262 = 0.5, Max. W/c ratio As per IS 456-2000 = 0.6
Calculation
Volume of broken stone required = (3/5.5) x 1.57 = 0.856 𝑚3
Volume of sand required = (1.5/5.5) x 1.57 = 0.471 𝑚3
Volume of cement = (1/5.5) x 1.57 = 0.285 𝑚3
=0.285 x 1440 = 441Kg
For 1 𝒎𝟑 of M20 (1:1.5:3)
Broken stone = 0.856 𝑚3
Sand = 0.472 𝑚3
Cement = 8.22 Kg
Self-curing agent
Table 2: PEG-Mix ratios for different PEG-400 (1%, 2%, and 3%)
For 3 cubes of self-curing concrete
SL.N
O
PEG
WITH
DIFFER
ENT
RATIO
S
NO
OF
CUB
ES
(7DA
YS)
NO
OF
CUB
ES
(14
DA
YS)
NO
OF
CUB
ES
(28
DA
YS)
TOT
AL
NO
CUB
ES
CEM
ENT
OPC(
Kgs)
FINE
AGGRE
GATE
(Kgs)
COARSE
AGGRE
GATE
(Kgs)
WAT
ER
(Lts)
PEG-
400
(mgs)
1 PEG-
1%
3 3 3 9 17.65 29.6 37.6 6.3 365
2 PEG-
2%
3 3 3 9 17.65 29.6 37.6 6.3 740
3 PEG-
3%
3 3 3 9 17.65 29.6 37.6 6.3 1100
International Journal of Pure and Applied Mathematics Special Issue
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Volume of PEG-1% = 40.6mgs (as per the volume of cement)
Volume of PEG-2% = 83.4mgs (as per the volume of cement)
Volume of PEG-3% = 124.5mgs (as per the volume of cement)
TEST RESULT FOR PEG (400)-1%
Table 3: Comparison of compressive strength for S.C.C and conventional concrete PEG-1%
COMPRESSIVE STRENGTH (N/mm2)
7 DAY STRENGTH 14 DAY STRENGTH 28 DAY STRENGTH
1 2 3 AVG 1 2 3 AVG 1 2 3 AVG
SELF
CURING 14.5 15
14.
5 14.6 21
21.
5
20.
5 21.5
30.
5
3
1 31 30.83
CONVENTIO
NAL CURING 15.85
16.
5 16 16.15
22.1
5
21.
5
22.
5 22.04
27.
5
2
8
28.1
5 27.88
LOADS ACTED
FOR PEG-1% 450 KN 435 KN
Compressive
stress N/mm²
1% Self curing30.83 N/mm2
Conventional concrete27.88 N/mm2
0
10
20
30
40
7 14 28
Com
pre
ssiv
e st
rength
(N/m
m²)
Days
PEG-1%
self curing concrete
conventional concrete
International Journal of Pure and Applied Mathematics Special Issue
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Graph 1: Gain strength in concrete in PEG-1%
Fig 2: Observation of crack in self-curing concrete PEG -1%
As per the following are the observations on compressive strength of concrete for 1% of PEG
It can be observed that conventional curing is reflecting change in strength over
period of 28 days i.e.) but losing strength after 28 days compared to self-curing
concrete[42-45].
Self-curing samples are showing loss of strength till day 14 but thereafter it is gaining
strength at the same rate when compared to conventional concrete.
If 28 day strength is compared, then self-curing is good to conventional curing in case
of 1% PEG-400 i.e.) there is increase in 11.8% of compression strength.