concrete made from ceramic electrical insulator waste

International Journal Of Advancement In Engineering Technology, Management and Applied
Science (IJAETMAS)
ISSN: 2349-3224 || www.ijaetmas.com || Volume 04 - Issue 01 || January- 2017 || PP. 15-23
CONCRETE MADE FROM CERAMIC ELECTRICAL
INSULATOR WASTE
YOUNUS A
Test Engineer, Farm Machinery Testing Centre, KCAET, Tavanur, Kerala, India
Abstract— Concrete which contains waste products as aggregate is called ‘Green’ concrete. Concrete
made with ceramic electrical insulator waste as coarse aggregate shows good workability, compressive, tensile and
flexural strengths and modulus of elasticity. Further, study of its durability will ensure greater reliability in its
usage.
Waste material produced by the sanitary ceramics industry can be reused as aggregate in structural
concrete mixes, as well as to analyze the economic and environmental benefits of this reuse. Firstly, aggregates
were classified in order to assess their suitability for concrete mixing. Once the necessary assays had been carried
out, different mixes were produced by gradually substituting part of the natural coarse aggregate with the
recycled ceramic material. These concrete mixes were tested to determine their structural properties and results
show that we can be optimistic when considering use of this kind of waste material in structural concrete.
Permeation characters are used widely to quantify durability properties of concrete. This is an experimental
investigation on the permeation characteristics [volume of voids and water absorption, chloride penetration,
and sorption] of concrete with ceramic electrical insulator waste coarse aggregate (hereafter it is called
recycled aggregate concrete) of six different water–cement ratios in comparison with those of corresponding
conventional concrete mixes From the results it has been observed that there is no significant change in the basic
trend of permeation characteristics of this recycled aggregate concrete when compared to the conventional concrete.
Keywords— Concrete , ceramic, electrical insulator, Waste material,
INTRODUCTION
The main objective of the reuse of material is to minimize the impact of human
activities on the environment and the planet. The use of alternative aggregate is a natural
step towards solving part of the depletion of natural aggregate, and the alternative
aggregate processed from waste materials would appear to be an even more sensible
solution. The need to develop concrete with non-conventional aggregates rose due to
environmental trends as well as economical reasons.
It has been estimated in a survey that about 30% of daily production goes as waste
in a ceramic electrical insulator industry, which is not reused in any form at present and
hence, piling up every day. There is pressure on the ceramic electrical insulator industries to
find a solution for its disposal. However the ceramic electrical insulator waste is highly
resistant to biological degradation forces. This waste is durable, hard and almost inert to
normal chemicals. Clay minerals become highly reactive when they are incinerated at
temperatures between 600-900°C and then ground to cement fineness. They are
mainly formed by siliceous and aluminous compounds. The loss of water due to thermal
treatments causes destruction of their crystalline structure, and they are converted into
unstable amorphous state. If they are then mixed with calcium hydroxide and water, they
undergo pozzolanic reaction and form compounds with enhanced strength and durability.
Therefore, they have a potential to be used in mortar and concrete. In this seminar, a wide
range of parameters of concrete containing waste ceramics as partial replacement of natural
aggregate is presented.
The movement of gases, liquids and ions through concrete is called permeation.
Different permeation processes for deleterious substances through concrete are diffusion,
absorption and permeability. The permeation of water in concrete provides a path for the
penetration of deleterious materials such as chloride and sulfate ions which can lead to
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International Journal Of Advancement In Engineering Technology, Management and Applied
Science (IJAETMAS)
ISSN: 2349-3224 || www.ijaetmas.com || Volume 04 - Issue 01 || January- 2017 || PP. 15-23
corrosion of reinforcement in reinforced concrete structures. The durability of concrete can
be assessed by the measurement of concrete permeation characteristics
Waste ceramic materials may become a cheaper but almost equivalent alternative to
metakaolin or ground granulated blast furnace slag, fly ash and other materials as
supplementary binder in concrete. The ceramic industry often produces calcined clays that
result from burning illite-group clays which are commonly used in the production of redclay ceramic products. A portion of these products (which amounts up to 2% depending on
producer and country) is discarded as scrap, thus constitutes industrial waste. The residues
of ceramic bricks and floor and roof tiles ground to a suitable fineness can though become
active pozzolans [1-3]. So, they have a potential to be used in mortar and concrete. The
measurements of properties of materials containing supplementary cementing materials are
similarly as with many other cement based composites mostly concentrated on mechanical
properties. This may not always be sufficient because superior mechanical properties are
often not accompanied by comparably good resistance against water or salt penetration.
Fig.1.a. Ceramic electrical insulator
Fig.1.b. Ceramic electrical insulator
waste materials
2. MATERIALS USED
Ceramic electrical insulator waste coarse aggregate
The ceramic electrical insulator waste (Fig. 2) is produced from the nearby ceramic
electrical insulator industry and their surfaces are de-glazed manually by chisel and
hammer. With the help of jaw crusher the de-glazed ceramic electrical insulator wastes are
broken into 20 mm maximum size coarse aggregate.
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International Journal Of Advancement In Engineering Technology, Management and Applied
Science (IJAETMAS)
ISSN: 2349-3224 || www.ijaetmas.com || Volume 04 - Issue 01 || January- 2017 || PP. 15-23
Crushed granite coarse aggregate
Crushed granite coarse aggregate of maximum size 20 mm is used in conventional
concrete.
Fig.2. Ceramic electrical insulator waste coarse aggregate & Crushed granite course
aggregate .
Other ingredients
Ordinary Portland cement 53Grade and river sand of specific gravity 2.67 and
fineness modulus 2.62 and potable water are used in both ceramic electrical insulator
waste coarse aggregate concrete and conventional concrete mixes.
MIX DESIGN
The mix design for the ceramic electrical insulator waste coarse aggregate concrete
is based on absolute volume method. By conducting trial mixes and proportion of these
mixes are adjusted to arrive at an optimum mix proportion, which is used
throughout the entire investigation. The ceramic electrical insulator waste coarse
aggregate concrete mixes are proportioned with six different water–cement ratios (0.35,
0.40, 0.45, 0.50, 0.55, and 0.60). The volume of water and coarse aggregate are kept
constant while the volume of cement and sand is varied. In a similar manner, by following
the absolute volume method .
WASTE FROM THE CERAMIC INDUSTRY
Test specimens
For each mix, six cubes (100 mm) and six cylinders (100 mm ɸ and 200 mm height)
are cast. The specimens are cast in steel molds and compacted on a vibrating table. They
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are de- molded after 24 h, and cured under water at 27 ± 2 °C for 28 days. Cubes are used
for testing of water absorption and volume of voids. The cylindrical specimens are cut
into four equal pieces of thickness 50 mm using a circular cutting saw. Out of the four
pieces the middle two pieces are used for sorption and chloride diffusion tests.
Saturated water absorption and volume of voids
The saturated water absorption and the volume of voids of ceramic electrical
insulator waste coarse aggregate concrete and conventional concrete cube specimens are
determined using the procedure given in ASTM C642-06. The cube specimen is dried in
an oven at a temperature of 105 °C for 24 h. After removing the specimen from the oven,
it is allowed to cool in dry air and weighed. The specimen is then immersed in water for
48 h and the saturated surface dry (SSD) weight of the specimen is measured. Then the
specimen is immersed in water and boiled continuously for 5 h. It was taken out, cooled,
surface moisture is removed by a towel and then the saturated surface dry (SSD) weight is
measured. Finally the specimen is suspended by a wire and the apparent weight was
measured in water. Percentage of water absorption is the ratio of the difference between
the weight of SSD sample after immersion and the weight of oven dry sample to the
weight of oven-dry sample. Volume of voids is the ratio of the difference between the
weight of SSD sample after boiling and the weight of oven-dry sample to the difference
between the weight of SSD sample after boiling and the apparent weight of sample in water.
Sorptivity
Sorptivity is a term used for water ingress into pores under unsaturated conditions
due to capillary suction. The sorptivity values of ceramic electrical insulator waste coarse
aggregate concrete and conventional concrete are determined by the measurement of water
absorption by capillary rise. The specimens are 100 mm diameter and 50 mm thick concrete
disc, saw-cut from the 100 mm X 200 mm cylinders. Each disc’s side surface is coated
with an impermeable epoxy coating to prevent the absorption through side surface during
the test
Fig.3 Experimental arrangement of sorptivity test
Then the specimens are oven dried at 105 ± 5 °C to constant weight. Initial weights are
taken after cooling to atmospheric temperature. The specimens are kept in a water tray
with small supports, as shown in Fig. 3. and the water level was maintained in such a
way that only the bottom 3–5 mm of the specimens were submerged in water. At any time t,
the water absorbed through the bottom of the specimen is the difference between the initial
weight and the weight at that time. These values can be used to determine the sorptivity S
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International Journal Of Advancement In Engineering Technology, Management and Applied
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ISSN: 2349-3224 || www.ijaetmas.com || Volume 04 - Issue 01 || January- 2017 || PP. 15-23
Where, I is the cumulative water absorption per unit area of inflow surface in g/mm2, t is
elapsed time in minutes and S is the sorptivity of concrete. S can be obtained from a linear
regression of I versus t1/2 plot.
Chloride diffusion
The resistance to chloride penetration is one of the simplest measures to determine
the durability of concrete. Separate specimens of similar size were cut from the same
cylinder for conducting RCPT. Test duration is 6hour.The RCP test is conducted on
saturated and surface dry specimens. Experimental arrangement is shown in Fig.4.The
specimens are placed in testing apparatus where one end of the specimen is exposed into a
solution containing NaCl solution and other end in NaOH solution. There increase the rate
of chloride penetration into specimen, thus speeding up the test. A constant 60V potential is
applied across the specimen. Current across the specimen is measured at least every 30
minutes during 6hour test. As the chloride penetrate deeper into the concrete, it become
more conductive and current reading increases. The rate of ingress of chlorides depends on
the pore structure of concrete.
Fig.4. Experimental arrangement of Rapid Chloride Penetration Test.
3. RESULTS AND DISCUSSION
Saturated water absorption
Fig. 5 shows the variation of saturated water absorption with water–cement ratio. Both the
ceramic electrical insulator waste coarse aggregate concrete and the conventional concrete
behave in a similar way and water absorption increases with increase in water–cement ratio.
Water absorption is defined as the transport of liquids in porous solids caused by surface
tension acting in the capillaries. In the present investigation, at the age of 28 days, the
water absorption of ceramic electrical insulator waste coarse aggregate concrete for different
water–cement ratios were 3.74–7.21% whereas for conventional concrete. it varies from 3.1%
to 6.52% for respective water–cement ratios
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International Journal Of Advancement In Engineering Technology, Management and Applied
Science (IJAETMAS)
ISSN: 2349-3224 || www.ijaetmas.com || Volume 04 - Issue 01 || January- 2017 || PP. 15-23
Fig.5. w/c ratio VS water absorption %.
Volume of voids
Volume of voids present in concrete depends on the mix proportion and properties
of aggregates used. Fig.6 shows the relationship between the water–cement ratio and the
volume of voids in ceramic electrical insulator waste coarse aggregate concrete and
conventional concrete. From the figure it can be seen that the volume of voids increases
with increase in water–cement ratio for both the ceramic electrical insulator waste
coarse aggregate concrete and the
conventional concrete.
Fig.6. w/c ratio VS volume of voids %
Sorptivity
After a period of sorption the initial rate of ingress observed decreases as the water has
accessed all the larger capillary pores. Sorptivity is now occurring via finer pores and
indicates the increasing importance of small pores with time. The average values of the
test results of sorptivity are represented by bar a chart in Fig. 7. The sorptivity reduces with
decrease in water– cement ratio for both ceramic electrical insulator waste coarse
aggregate concrete and conventional concrete.
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International Journal Of Advancement In Engineering Technology, Management and Applied
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Fig.7. w/c ratio VS sorptivity
Chloride diffusion
As expected, the RCPT. charges reduce with decrease in water– cement ratio, the test
results are presented in the Fig. 8. When capillary pores are relatively dry, absorption
dominates and when they are relatively saturated, diffusion becomes the dominant transport
process. In this investigation sorptivity specimens were dry and RCPT specimens were
saturated. The concrete disc specimens for sorptivity and RCPT were similar in size, cut
from the same cylindrical specimen and both the tests were conducted for a period of 6 hour
duration
Fig.8. w/c ratio VS RCPT charge
Discussion
Theoretically, the factors controlling the permeation characteristics of concrete
materials are the relative volume of paste matrix, the pore structure of the bulk matrix and
the interfacial transition zone (ITZ) around the aggregate particle. Various studies show
that the rougher the aggregate surface texture used in concrete for the better the bonding.
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International Journal Of Advancement In Engineering Technology, Management and Applied
Science (IJAETMAS)
ISSN: 2349-3224 || www.ijaetmas.com || Volume 04 - Issue 01 || January- 2017 || PP. 15-23
the difference of the test results of permeation characteristics between the ceramic
electrical insulator waste coarse aggregate concrete and the conventional concrete is due to
an increase in porosity of the ITZ [5], the reason perhaps may be due to the smooth surface
texture of the ceramic electrical insulator waste coarse aggregate which is responsible for
the bonding of aggregate with surrounding mortar. All the transport processes occur in the
pore system and this depends on the total pore volume, pore size, threshold pore radii and
the continuity of the capillary pores. The results from microstructural study seemed to
suggest that the addition of mineral admixtures like pulverized fuel ash, grounded
granulated blast furnace slag, micro silica, etc. to ceramic electrical insulator waste coarse
aggregate concrete may improve the particle packing density of ITZ and in turn
permeation characters will be improved.
:
Advantages
 Economical
 Ambient temperature hardened material
 Energy efficiency
 Excellent resistance to water
 High temperature resistance
 Ability to consume waste
 Less maintenance required
:
Limitations
 Quasi-brittle failure mode
 Low tensile strength
 Low toughness
 Formwork is needed
 Long curing time
 Working with cracks
4. CONCLUSIONS
The permeation characteristics of ceramic electrical insulator waste coarse aggregate
concrete were comparable to those of conventional concrete.
 The permeation characteristic values increase with increase in water–cement ratio
for both the ceramic electrical insulator waste coarse aggregate concrete and
the conventional concrete.
 The difference in the test results of permeation characters are due to the surface texture
of ceramic electrical insulator waste coarse aggregate.
 The permeation characteristics of ceramic electrical insulator waste coarse
aggregate concrete may be improved by adding mineral admixtures like fly ash, slag,
micro silica, etc
 The ceramic electrical insulator waste coarse aggregate can be used for the production
of concrete.
5.REFERENCES
[1] Neville AM. Properties of concrete. London: Pitman Publishing Limited; 1981
[2] Park SG. Recycled concrete construction rubble as aggregate for new concrete, New
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International Journal Of Advancement In Engineering Technology, Management and Applied
Science (IJAETMAS)
ISSN: 2349-3224 || www.ijaetmas.com || Volume 04 - Issue 01 || January- 2017 || PP. 15-23
Zealand; 1999.
[3] Khaloo AR. Crushed tile coarse aggregate concrete. Ceramic Concrete Aggregates
1995 [4] Topcu IB, Guncan NF. Using waste concrete as aggregate. Ceramic Concrete
1995
[6] Ramamurthy K, Gumaste KS. Properties of recycled aggregate concrete. Indian
Concrete J 1998
[7] Basri HB, Mannan MA, Zain MFM. Concrete using waste oil palm shells asaggregate
1999
[8].Milind Gupta &A K Pandey. Experimental studies on brick masonry in compression
The Indian Concrete Journal –2012
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