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EFFECT OF RICE HUSK ASH ON THE STRENGTH AND DURABILITY PROPERTIES OF CONCRETE
NATIONAL INSTITUTE OF TECHNOLOGYAGARTALA
DEBASREE GHOSH JUNIOR ENGINEER (CIVIL DEPT)WORK OF 2014-8TH SEM
Chapter:1- Introduction Chapter:2- Objective Chapter:3- Literature Review Chapter:4- Material Properties Chapter:5- Experiments required to observe the effect Chapter:6- Observation Chapter:7- Conclusion. Chapter:8- Future Scope References
CONTENTS:
Concrete is the most vital material in the modern construction.
RHA (RICE HUSK ASH) Concrete is the special type of concrete, that
are produced by unusual techniques. Concrete is by definition a
composite material consisting essentially of a binding medium and
aggregate particles with definite proportion of water and it can take
many forms.
RHA Concrete do have advantages as well as disadvantages. The
character of the concrete is determined by quality of the paste. That is
its workability.
Chapter:1-INTRODUCTION
Cont…
CONCRETE
COARSE AGGREGA
TE
FINE AGGREGA
TE
BINDING MATERIA
L
1.1 HOW CONCRETE FORMS:
WATER
Cont…
CEMENT
LIME
LIME-CEMENT
1.2 DESCRIPTIVE DIAGRAM
BINDING MATERIAL
COARSE AGGREGA
TE
STONE
BRICK CHIPS
Cont…
SANDSTON
E DUST
RHA
SURKHICINDER
FINE AGGREGATE
Cont…
Effect of Rice Husk Ash depends on the amount of
replacement and on the chemical and physical
characteristic of replaced material.
Here we will introduce Rice Husk Ash as a replacement of
Fine aggregate with different percentages.
Investigations for the requirement of water for different
percentages of RHA, amount of replacement and the
change in the behaviour of concrete is done.
During the milling of paddy about 22 % of the weight of
paddy is received as husk. This husk is used as fuel in the
rice mills. This husk contains about 75 % organic volatile
matter which burns up and the balance 25 % of the weight
of this husk is converted into ash during the firing process,
which is known as rice husk ash (RHA).
It is highly reactive in nature and obtained by combustion
process.
1.3 Rice Husk Ash (RHA)
Cont…
It is a part of waste ashes. The landfill of waste ash is a
problem of environmental effects because these waste ashes
are not used in any work without construction.
It is a green house agent and increases the green house effect
adversely and becomes non-eco friendly. Many researches
had been done to find out its solution.
Cont…
What we should do?
As Rice Husk Ash Is Non- Eco Friendly
LET US OBSERVE BY EXPERIMENTAL WAY
RHA has two roles in concrete manufacture, as a substitute
for fine aggregate, reducing the cost and weight of concrete
in the production of low cost building blocks.
Therefore, a large number of researchers have been directed
toward the utilization of waste materials.
It increases the durability of concrete.
Chapter:2- OBJECTIVE
Cont…
Rice Husk Ash (RHA) is an agricultural waste product, and
how to dispose off it is a problem to waste managers. Use of
RHA reduces this type of problems.
As it is a waste form in environment there is an increasing
importance to preserve the environment in the present day
world. RHA from the parboiling plants is posing serious
environmental threat and ways are being thought of to
dispose them.
Cont…
Therefore some research work has been done and found that
RHA can be used in construction purpose as a replacement
for cement and sand.
The concrete material is the expensive material and used in
all over India, if all-important expensive material is partially
replaced with more natural, local and affordable material like
RHA will not only take care of waste management but will
also reduce the problem of high cost of concrete and housing.
Cont…
RHA can be used for low cost building (say less important
building specially). But in some specified amount of RHA can
be used.
It is also found that RHA, fly ash with some steel fibre shows
better strength properties than normal concrete.
By using this Rice husk ash in concrete as replacement, the
emission of green house gases can be decreased to a greater
extent.
From the Indian Concrete Journal (ICJ), Journal of
Cement and Concrete Research, Journal of Advanced
Cement based Materials, American Concrete Institute
(ACI) publications literature review has been obtained.
It gives the brief idea about the effect of different types of
ashes on concrete when it is replaced in the place of sand
or cement.
Chapter:3- LITERATURE REVIEW:
Cont…
Different researcher gives their opinion about the
replacement of RHA.
◦ Aramraks et al., (2006) did some experimental study to find out the
feasibility of using ash as fine aggregate in structural grade concrete
through the investigation of the physical and mechanical properties
of concrete in fresh and hardened state.
◦ Aggarwal et al., (2007) studied the effect of use of ash for various
percentages (0-50%) replacement of fine aggregates with ash can
easily equated to the strength development of normal concrete at
various ages.Cont…
◦ Kasemchaisiri et al., (2008) presented the test results of fresh
concrete, the use of ash resulted in the reduction of compressive
strength due to increase of porosity of hardened concrete.
◦ Rocha et al., (2009) investigates the influence of ash as a
replacement for FA, the result shows ash are susceptible to water loss
by bleeding and the higher the percentage of ash used as a natural
sand replacement the lower the deformation through plastic
shrinkage.
Cont…
◦ Lee et al., (2010) evaluated the utilization of ash as FA and CA in
high-strength concrete. It was found that the slump flow of fresh
concrete was slightly decreased from 530mm to 420mm when coarse
ash was replaced 100% of normal CA, while fine ash did not affect the
slump flow.
◦ Chua Wei Leong et al., (2010) studied the use of municipal solid
waste (MSW) incineration ash as aggregate for the production of light
weight concrete, the compressive strength s of concrete in the three out
of the four test series were able to achieve the ASTM standard
requirement on light weight concrete.Cont…
◦ Sun et al., (2008) applied low-profile piezoceramic transducers and it
shows the differences in amplitude between wave packets are sensitive
to the cracking process of concrete with externally applied loads.
Literature review is important to have the knowledge of
amount of replacement and its requirement.
It gives some co-relationship between different form of
replacement that has been observed during experiments of
different researchers.
Physical State
Appearance Particle Size
Color Odour Specific Gravity
Solid – Non
Hazardous
Very fine powder
25 microns
Grey Odourless 1.22
Chapter:4- MATERIAL PROPERTIES:
Rice husk ash is pozzolanic material and highly reactive.
RHA is high in silica content in the form of noncrystalline or
amorphous material silica.
It is also durable in nature, several researchers have studied the
durability variation of the concrete with pozzolanic materials.
Rice Husk Ash: 4.1 TABLE
Cont…
After replacement of Fine aggregate with RHA we have the
following proportions for M20 grade concrete with different
percentages of Fine Aggregate replacement with RHA are as
follows:-
% Cement Fine aggregate
Coarse Aggregat
e
RHA
20% 1 1.08 2.66 0.1340% 1 0.81 2.66 0.2660% 1 0.54 2.66 0.39
4.2. TABLE
Compressive Strength Test on:◦ Cube (150mm x150mm x 150mm)◦ Cylinders (150mmØ x 300mm)
Split Tensile Strength Test on:◦ Cylinders (100mmØ x 200mm)
Flexural Strength Test on:◦ Beam (100mm x 100mm x 500mm)
Rapid Chloride permeability Test Young’s Modulus Test Non-Destructive Test
Chapter:5- Experiments Required To Observe The Effect Of RHA
Cont…
The strength of the concrete
depends on the properties and
proportions of the constituent
materials, rate of loading, the
method of testing and the
specimen geometry.
The cube specimen generally
exhibit 20 to 25 percent higher
strength than cylindrical specimen
due to specimen geometry.
Compressive Strength Test:
Cont…
The split tensile strength test is the
indirect measurement of the tensile
strength by placing a cylindrical
specimen horizontally between the
loading surfaces.
This method is consists of applying a
diametric compressive force along the
length of a cylindrical specimen.
Split Tensile Strength Test
Cont…
Flexure strength test is the ability check
of a beam or slab to resist failure in
bending.
Generally flexure strength value is
about 2 to 20 percent of compressive
strength.
The flexure strength of the specimen is
expressed as the modulus of rupture fb.
Flexural Strength Test on:
Cont…
Rapid Chloride Permeability Test
Rapid chloride permeability Test has been conducted
to find out the permeability of different concretes.
Rapid chloride test was designed to determine the
resistance of concrete to the penetration of chloride
ions, an indicator of its permeability.
Charge passed (coulombs) Chloride ion penetrability
>4000 High
<100 NegligibleCont…
The elastic modulus of concrete is a very
important mechanical parameter reflecting the
ability of the concrete to deform elastically.
The modulus of elasticity or Young’s modulus
is defined as the slope of the stress-strain curve
within the proportional limit of a material.
The secant modulus is defined as the slope of
straight line drawn from the origin of axes to
the stress-strain curve
Young’s Modulus Test
Cont…
For Non-Destructive Test, piezoelectric
transducers and Ultrasonic Pulse Velocity
Method have been used to find out the crack
depth for conventional concrete and rice
husk ash concrete.
The basic principle of crack detection is that,
if the crack is at appreciable width and
considerable depth, perpendicular to the test
path, no signal will be received at the
receiving transducer.
Non-Destructive Test
COMPRESSIVE STRENGTH OF CONCRETE CUBE WITHOUT RHAFIG.1 Compressive strength of M20 grade concrete cube (N/mm2)
Chapter:6- OBSERVATION
1day 3days 7days 28days020406080
100
13.6 14.82 23.2 25.4514.22 14.6821.5 25.3113.72 15.522.5
27.83
Series1 Series2 Series3Cont…
COMPRESSIVE STRENGTH OF CUBE WITHOUT RHAFIG.2 Compressive strength of M25 grade concrete cube (N/mm2)
1day 3days 7days 28days0102030405060708090
100
14.95 15.83 26.23 29.5615.26 15.66
25.4632.4517.72 18.21
24.3328.23
Series1 Series2 Series3Cont…
COMPARISON BETWEEN DIFFERENT BEHAVIOUR OF CONCRETE
FIG. 3 Compressive strength of concrete cube without RHA(N/mm2)
FIG. 4 Compressive strength of concrete cube with RHA(N/mm2)
1 day 3 days 7 days 28 days
13.85 15
22.42
26.2
15.98 16.57
25.3430.08
M20 M25
1 day 3 days 7 days 28 days
8.0312.6
15.72
20.819.17
13.217.16
22.44
10.49
14.7
18.12
22.8
M20 with 60% RHA M20 with 40% RHAM20 with 20% RHA
Cont…
FIG. 5 Compressive strength of M20 grade concrete cube with RHA(N/mm2)
1 day 3 days 7 days 28 days
8.03
12.6 15.72 20.819.17
13.217.16 22.44
10.49
14.7
18.1222.8
13.85
15
22.42
26.2
Comparison between M20 grade without RHA and with 20% , 40% & 60% RHA
M20 with 60% RHA M20 with 40% RHA M20 with 20% RHA M20
Cont…
M25 M20 20% RHA 40% RHA 60% RHAWithout RHA M20 With RHA
0
5
10
15
20
25
30
35
23.22
18.0315.78
14.0711.9
31.83
24.15
19.4
13.83
10.72
28.34
20.17
16.76 14.76
13.47
Specimen 1 Specimen 2 Specimen 3
COMPRESSIVE STRENGTH REPRESENTATION OF CYLINDERS
FIG. 6 Total Compressive Strength of cylinder in N/mm2
Cont…
FIG. 7 Total representation of Split tensile Strength of cylinder in N/mm2
TOTAL REPRESENTATION OF SPLIT TENSILE STRENGTH
M25 M20 20% RHA 40% RHA 60% RHAWithout RHA M20 With RHA
2.74
1.92
1.67
1.43
1.18000000000001
2.322.09
1.731.57
1.24
2.41
2.13
1.79
1.391.15999999999999
2.49
2.05
1.73
1.46
1.19000000000001
Specimen 1 Specimen 2 Specimen 3 Average
Cont…
FIG. 8 Flexural strength of beam (100mm x100mm x500mm)
FLEXURAL STRENGTH OF BEAM WITH AND WITHOUT RHA
Strength a Strength a Strength aM20 M25 M20 (20% replacement)
Without RHA With RHA
0
5
10
15
20
25
30
The concrete specimen so prepared gives the highest
compressive strength at 7days compared to 1day and 3days.
The compressive strength of concrete varies with the type of
curing and the amount of curing done before the test.
Experimentally it is found that 28 days strength is found to
be more than 7 days.
RHA replacement, M20 with 20% replacement shows higher
strength values than M20 with 40% replacement.
Chapter:7- CONCLUSION:
Cont…
M20 with 40% replacement shows higher strength values
than M20 with 60% replacement. But three of these values
are found lesser strength than the specimens tested without
rice husk ash replacement.
Use of RHA showing a drastic increase in the amount of
water required during the preparation of specimens.
Standard mixes of concrete uses less amount of water as
compared to the mixes replaced with rice husk ash.Cont…
We can conclude that in cases of lack of fine aggregate we
can use rice husk ash in place of fine aggregate up to a
certain extent.
It increases the porosity of concrete specimen and hence
decrease the strength of concrete, but lesser amount of
replacement will show very negligible change in the
strength, so in case of having shortage of fine aggregate we
can use some amount rice husk ash.
In future, the availability of rice husk ash as a replacement
for fine aggregate can be used if the properties of rice husk
ash concrete are similar to standard concrete.
Rice Husk Ash decreases the workability of concrete as the
water requirement increases. But if we use RHA, Fly ash
with some steel fiber, it will increase the strength of
concrete. Hence, can be used as a normal concrete in
future.
Chapter:8- FUTURE SCOPE:
[1] Assumed standard deviations for target mean strength
of concrete taken from table 11, 22 page no. 491-492 of
CONCRETE TECHNOLOGY by M.S. Shetty.
[2] Mix proportions according to IS: 456-2000
[3] Mix design as per IS: 10262-2009
[4] Aggregates in Concrete. Asian Journal Of Civil
Engineering (Building And Housing) Vol. 8, No. 1 (2007)
Pages 49-62.
References:
Cont…
[5] Qasrawi H.Y., Marie I.A., The use of USPV to anticipate failure in
concrete under compression. Cement and Concrete Research 33 (2003)
2017–2021. [6] Kasemchaisiri R., Tangtermsirikul S., Properties of Self-Compacting
Concrete in Corporating Ash as a Partial Replacement of Fine Aggregate.
ScienceAsia 34 (2008): 087-095.
[7] Kim H.K.,Use of power plant ash as fine and coarse aggregates in
high-strength concrete.
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