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DURABILITY RESPONSE OF HIGH PERFORMANCE CONCRETE
WITH METAKAOLIN AND RICE HUSK ASH
Swaminathen1, Prof. Robert Ravi2
1Research Scholar, Sree Sakthi Engineering College, Tamil Nadu, India. 2Professor SSM Institute of Engineering and Technology, Tamil Nadu, India.
Abstract - Concrete is widely used construction material in developing and developed countries in a structure. After several
research results across different countries, growth of concrete is eyed forward towards the growth of its performance, where the
high performance concrete is developed. This high performance concrete holds different enhanced property in it such as durability
by proving resistive to chemically varying atmosphere, improved economic status, reduction of CO2 by reducing the amount of
cement ( cement has been partially replaced by mineral admixtures-MK & RHA) , increased Ecology balance by balancing natural
resources consumption and furthermore. The vision of this paper extends towards the effect of mineral admixtures on durability
properties of high performance concrete. To attend effective results such as Low porosity, sorptivity and proportioning of materials
is always been the key. M60 grade of concrete is used in this work. Curing is preferred to3, 7, 14, 28, 56, 90 days with 3 sample
blocks (different combinations) each curing day. This different mixture of concrete is preferred upon further tests where the
durability is determined cautiously. It is evident through researches that the durability performance can be further induced
positively by critically proportioning the mineral admixtures to concrete.
Key Words: Durability, Water absorption, Porosity, Sorptivity
1. INTRODUCTION
HPC is the concrete that is proving to be effective and efficient than Ordinary concrete. Since last decade, the fashion of
using supplementary cementing materials has become integral part of HPC. These supplementary cementing materials
are chosen from the source that requires less energy and time, such as Natural materials, by-products or industrial
wastes. The application of pozzoloanic materials in HPC proves to reduce the crystalline components – Calcium
hydroxide in particular; simultaneously the thickness of the interfacial transition zone is also reduced. Thus densification
of the interfacial transition zone allows for efficient load transfer between the cement mortar and the course aggregate
contributing to the strength of the concrete.
As recent trend, pozzalonic material like GGBFS, fly ash, Silica fume, Metakaolin and Rice Husk Ash blends are used
in HPC to make it durable. In present research, MK and RHA is used as pozzolonic materials that is said to increase the
mechanical property of concrete .This HPC prepared with supplementary cementing materials and super plasticizer- in
fresh and hardened state, has got better performance than OPC concrete. On comparing HPC to OPC concrete, HPC has
more binding property, less water requirement, coarser fine aggregate and small size of aggregate which improves the
durability of concrete.
Rice husk (RH) is an agro waste product. Countries like Malaysia, India, China and Bangladesh (Asian countries)
produce tons of RH every year. Super pozzolona Rice Husk Ash (RHA) is obtained by controlled burning and
incineration. SiO2 content is rich in RHA, so it becomes highly reactive to lime. MK is naturally available and
sometimes a by-product from industries. MK can be obtained by heating the Kaolin mineral. Kaolin is a fine particle
size, white clay that is abundantly used material in the production of porcelain. Inclusion of MK as supplementary
cementing materials results in enhancement such as strength, durability and less consumption of cement in concrete. The
usages of MK have reduced the thickness of interfacial zone and porosity of hardened concrete, the adhesion between
cement paste and aggregate is also enhanced. This is due to the finer property of MK than cement particles.
International Journal of Scientific Research and Review
Volume 7, Issue 2, 2018
ISSN NO: 2279-543X
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The two materials namely MK and RHA are notably useful pozzolona cement material, which enhances the workability
and mechanical property of concrete when added. In the present work, experimental study was carried out to find the
effect of combination of MK and RHA on workability, strength, durability and reported the results. M60 grade
concrete with 53 Grade OPC Priya Cement was used, and mixes are prepared by replacing part of cement (OPC) with
MK and RHA. Thus the replacement levels are as follows 0%+0%, 5%+10%, 7.5 % + 10 %, 10 % + 10 %, 5 % + 12.5
% ,7.5 % + 12.5 %, 10 % + 12.5 %, 5 % + 15 % ,7.5 % + 15 % ,and 10 % + 15 % (MK+ RHA ) respectively .
2. MATERIALS AND METHODS
2.1 Cement
The cement that was accounted in this research is Ordinary Portland Cement (OPC) 53 grade Priya cement with specific
gravity 3.11 that is frequently available in the market. The properties of cement were understood in accordance with IS –
8122: 1989 with Fineness – 7% (<11%); Consistency – 34%; Initial setting time – 65minutes (>29 minutes); Final
setting time – 360minutes (<601 minutes)
2.2 Coarse aggregate
These are irregular shaped hard materials used as filler material in concrete. In this present work 10mm and 12.5mm size
coarse aggregates are used. The different characteristics like specific gravity, bulk density, fineness modulus, flakiness
index and elongation index value of coarse aggregate were obtained as 2.98, 1886.35kg/m3, 5.5, 19% and 8%
respectively.
2.3 Fine aggregate
River sand of a better texture and quality is preferred here as fine aggregate which is sieved through 4.75 mm sieve.
Tests such as specific gravity bulk density and fineness modulus were carried out and the values obtained where 2.37,
189 0.81 kg per meter cube and 3.78 respectively.
2.4 Chemical admixtures
Low water binder ratio (w/b) and very fine particles in form of mineral admixtures (such as MK and RHA) in HPC
makes it look special when it comes to durability. The above features are achieved by effective dispersion (to produce
proper microstructure of hardened concrete) of concrete. For, no further increase in the unit water and cement contents
in the mix for workability - chemical admixture is being essential in addition. At present, super plasterer named
CONPLAST SP 430 is used in this research which produces workable concrete at low water binder ratio, of course that
is required. CONPLAST SP 430 complies with BIS: 9103-1999 and BS: 5075 part 3 ASTMC 494 type B as a HRWRA.
2.5 Mineral admixtures
2.5.1 Rice husk Ash
Rice husk Ash that is commercially available is used for this research, supplied by N K Enterprise Orissa. It's physical
and chemical properties were obtained from laboratory in Karunya University Coimbatore.
2.5.2 Metakaolin
Metakaolin is supplied by Astra Chemicals Chennai for this research. This Metakaolin was sieved through 100micron
sieve and used in this research.
3.0 SEM ANALYSIS
This scanning electron microscopy for MK and RHA was done, in laboratory of Karunya University Coimbatore which
is shown in figure 1,2, 3and 4 respectively.
International Journal of Scientific Research and Review
Volume 7, Issue 2, 2018
ISSN NO: 2279-543X
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Fig: 1 SEM for Rice Husk Ash
Fig: 2 EDAX for Rice Husk Ash
Fig: 3 SEM for Metakaolin
Fig: 4 EDAX for Metakaolin
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4. CASTING OF SPECIMENS
About 155 trial specimens were casted with the aid of absolute volume method of mix design. Those specimens are
made replacing the OPC with different proportions of MK and RHA, the replacement level of OPC by MK and RHA
counts like 0%+0%, 5%+10%, 7.5 % + 10 %, 10 % + 10 %, 5 % + 12.5 % ,7.5 % + 12.5 %, 10 % + 12.5 %, 5 % + 15 %
,7.5 % + 15 % ,and 10 % + 15 % (MK+ RHA ) with w/c ratio of 0.31 in the production of this HPC. Compressive
strength of this HPC cubes we're found by immersing them in water for 28 days. The fresh concrete was placed into the
steel mould of size 150X150X150 mm and compacted in 3 layers. These HPC specimens were made in compliance with
BS 1881-108:1983.
Fig: 5 HPC Cubes are in mould
5. EXPERIMENTAL INVESTIGATIONS
5.1 Workability
The workability of concrete is governed by the water requirements at the time of mixing, where in conventional concrete
it is concluded on the basis of maximum size of aggregate used. When mineral admixtures such as MK and RHA with
more fineness and more surface area were added, the physical characteristics of concrete greatly influence the water
demand and workability of mix. Superplastizer are added in order to maintain the workability, interns of slump value-50
to 100 mm. These superplasticizers which get adsorbed on cement particles produce a strong negative charge that helps
to reduce the surface tension of excess water in concrete considerably, enhancing the fluidity of the concrete positively.
The workability results achieved in this study is in line with the studies conducted by [2].
Table: 1 Workability Results Mix Name RHA
(%)
MK
(%)
Slump in mm
Mc 0 0 110
M1 10 5 95
M2 10 7.5 80
M3 10 10 74
M4 12.5 5 72
M5 12.5 7.5 50
M6 12.5 10 42
M7 15 5 40
M8 15 7.5 35
M9 15 10 20
5.2 Cube compressive strength
Variation in compressive strength of this high performance concrete containing different properties of M K and RHA is
sorted in the graph below- figure 6, which also indicates difference in strength at 3, 7,14, 28, 56 and 90 days. The
observations of compressive strength at age of 7 days for 60 grade concrete mixers containing 0%+0%, 5%+10%, 7.5 %
+ 10 %, 10 % + 10 %, 5 % + 12.5 % ,7.5 % + 12.5 %, 10 % + 12.5 %, 5 % + 15 % ,7.5 % + 15 % ,and 10 % + 15 %
International Journal of Scientific Research and Review
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ISSN NO: 2279-543X
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Cement replacement (by MK And RHA ) were 40.98,45.54,47.65,46.58,49.44,56.44,51.28,54.37,53.79,,and 44.34
N/mm2 respectively. At the age of 28 days it is found as 60.20, 55.58, 59.10, 59.91, 69.88, 71.42, 66.50, 63.16, 62.22,
and 61.12N/mm2 were respectively. On carefully observing, the cube compressive strength at age of 28 days gradually
increased from 55.58 to 71.42 N/mm2 up to the mix 7.5+ 12.5 % (from 5 + 10 %) and started to reduce after that. From
the table 2, it is clear to understand the compressive strength through all the ages for the sample cubes. It is observed
that the strength is increasing from M1 and reducing from M6. From the above results it is evident that the maximum
compressive strength is attained in the mix containing 7.5 % + 12.5 % replacement of M K and RHA for M60 grade
cement concrete. The strength increasing from 0% + 0% peaks at 7.5% + 12.5% (MK+RHA replacement for cement)
and gradually decreases until 10% + 15% (MK+RHA replacement for cement) mix proportions. [3] Inspected the
compressive strength of MK and RHA blended cement mortar in percentage are 20.9% at 15% replacement of Rice
Husk Ash 17.42% at 25% replacement of Metakaolin and 24.61% at 30% replacement of Rice husk ash for a Metakaolin
combination of (1:1 ratio).
Table: 2 Compressive Strength of M60 Grade Concrete cubes with different ages Mix Name RHA
(%)
MK
(%)
Compressive strength in N/mm2
3 days 7 days 14 days 28 days 56 days 90 days
Mc 0 0 30.23 40.98 48.7 60.20 64.90 67.30
M1 10 5 34.09 45.54 50.71 55.58 60.76 65.10
M2 10 7.5 35.69 47.65 53.89 59.10 63.71 69.80
M3 10 10 40.23 46.58 52.0 59.91 68.99 73.25
M4 12.5 5 44.91 49.44 57.59 69.88 75.81 79.34
M5 12.5 7.5 49.59 56.44 63.44 71.42 78.86 82.56
M6 12.5 10 45.46 51.28 59.42 66.50 76.37 80.61
M7 15 5 41.33 54.37 56.87 63.16 73.44 78.62
M8 15 7.5 37.20 53.79 58.56 62.16 68.84 74.76
M9 15 10 33.07 44.34 55.23 61.12 65.36 69.76
Fig: 6 Influence of MK and RHA on compressive strength of mixes at various ages
6. DURABILITY
6.1 Saturated Water Absorption
The results of saturated water absorption test of different number of concrete mixers at age 28 and 90 days are listed in
table 3. The graph 7 indicates the impact of MK and RHA on the water absorption of concrete mixers and the variation
of saturated water absorption respectively. The saturated water absorption of M60 grade high performance concrete
mixes for M1 to M9 mixes at age of 28 days is 2.62, 1.96, 1.72, 1.56, 1.44, 1.30, 1.42, 1.67, and 1.85% respectively.
Further, at the age of 90 days it is found as 2.02, 1.67, 1.47, 1.42, 1.32, 1.22, 1.27, and 1.27% respectively. Optimum
0
10
20
30
40
50
60
70
80
90
3 days 7 days 14 days 28 days 56 days 90 days
Com
pre
ssiv
e s
trength
(M
pa)
% Replacement of MK and RHA
International Journal of Scientific Research and Review
Volume 7, Issue 2, 2018
ISSN NO: 2279-543X
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percentage of cement replacement level by MK and RHA for high performance concrete mix was 7.5 + 12.5% to
accomplish the minimum value of saturated water absorption.
The exploratory outcomes prove the percentage of saturated water absorption of the high performance concrete mixers
containing MK and RHA is lower when compared to high performance concrete mixes without MK and RHA . It is
noted that 25 to 50% less water is observed in, at the age of 28 days for the concrete with MK and RHA when compared
to mixes without MK and RHA. This less water requirement indicates the pozzolonic reaction and micro Pore filler
effects of MK and RHA. The important thing to be noted is the high performance concrete having 7.5 + 12.5% MK and
RHA results in the minimum value of SWA and it also improves the microstructure of concrete mixers (fine and
discontinuous pore structure). [4] Obtained water absorption in the order of 2.9 to 4.78% for concrete mixes containing
cement replacement materials.
Table: 3 saturated water absorption results of M60 grade mixes Mix Name RHA
(%)
MK
(%)
Saturated water absorption at 28 days (%) Saturated water absorption at
90 days (%)
Reduction in water absorption
compared to normal concrete
at 28 days (%)
MC 0 0 2.62 2.02 -
M1 10 5 1.96 1.67 25.08
M2 10 7.5 1.72 1.47 34.25
M3 10 10 1.56 1.42 40.37
M4 12.5 5 1.44 1.32 44.95
M5 12.5 7.5 1.30 1.22 50.31
M6 12.5 10 1.42 1.27 45.72
M7 15 5 1.67 1.29 36.16
M8 15 7.5 1.85 1.34 29.28
M9 15 10 1.98 1.39 24.31
Fig: 7 Influence of MK and RHA on water absorption of M60 mixes
6.2 Porosity
Porosity test for high performance concrete Blended mixes are carried out and the results at the age of 28 days and 90
days are produced in table 4. Figure 8 indicates the impact of MK and RHA on porosity in concrete (present HPC) and
change in porosity with different percentage of cement replacement material respectively. The effective porosity of this
MK and RHA based blended mixes with w/b ratio of 0.31 at the age of 28 days and 90 days varies from 2.97 to 2.42 and
2.62 to 2.22 respectively. On observing experimental results, the porosity in high performance concrete blended mixes
with MK and RHA are noted less in comparison with high performance concrete mixes without admixtures.
MK and RHA are most functional to reduce porosity in concrete then improving compressive strength. Through the
observations and graph, MK and RHA based high performance concrete showed lesser porosity values (Up to 7.5 + 12.5
% mix quantity of M K+RHA) in contrast with control concrete. To understand in percentage, MK and RHA based
blended mixes at the age of 28 days indicated porosity value of 7 to 24 percentages lesser than concrete mixers without
0
0.5
1
1.5
2
2.5
3
28 days 90days
Wate
r absorp
tion
% Replacement of MK+RHA
International Journal of Scientific Research and Review
Volume 7, Issue 2, 2018
ISSN NO: 2279-543X
http://dynamicpublisher.org/127
MK and RHA. For concrete mix containing fly ash, [5] observed porosity value as 7.22 to 8.06%. The porosity value in
the present investigation is seen to be reasonably positive on comparing the investigation held by [5]. The present
investigation also demonstrates superior durability characteristics of MK and RHA blended high performance concrete
mixers.
Table: 4 Porosity results of M60 mix Mix Name RHA
(%)
MK
(%)
Porosity at 28 days (%) Porosity at 90 days (%) Reduction in porosity compared to normal
concrete (28 days) %
MC 0 0 3.22 2.80 -
M1 10 5 2.97 2.62 7.76
M2 10 7.5 2.77 2.54 13.98
M3 10 10 2.62 2.45 18.63
M4 12.5 5 2.52 2.32 21.74
M5 12.5 7.5 2.42 2.22 24.84
M6 12.5 10 2.47 2.57 23.29
M7 15 5 2.52 2.62 21.74
M8 15 7.5 2.57 2.67 20.19
M9 15 10 2.59 2.73 19.57
Fig: 8 Influence of MK and RHA on porosity of M60 mix
6.3 Sorptivity
Sorptivity results obtained from the test for high performance concrete mixers at age of 28 and 90 days are tabulated in
5. Figure 9 indicate the impact of MK and RHA on sorptivity in concrete mixes and variation of sorptivity with different
percentage of MK and RHA respectively. At the age of 28 days and 90 days, sorptivity of mixes M1 to M9 varies from
0.026 to 0.036 (0.026 to 0.016 in decrement and 0.021 to 0.036 increment) and 0.043 to 0.029 ( 0.43 to 0.014 in
decrement and 0.019 to 0.029 in increment) for respective age of concrete. Experimental results show that the sorptivity
of high performance concrete with MK and RHA is lower when compared to high performance concrete without MK
and RHA. Optimum percentage of cement replacement by MK and RHA for high performance concrete is 7.5 + 12.5 %
for attaining minimum value of sorptivity. [6] produced, sorptivity values comes down at 28 and 90 days with
enhancement of blend such as fly ash, rice husk Ash and egg shell powder, ie., Less sorptivity than control concrete. [7]
Denoted, in plain cement concrete, transition zone is generally less dense than the bulk cement parts and continuous
small amount of plate like crystals of Ca (OH)2 which can be reduced with addition of pozzolanic material (RHA and
FA ). Fine particle size of RHA and FA are principle reason for the advancement of discontinuous and tortuous pore in
concrete structure.
Sorptivity is a function of pores, pore size and continuity of pores inside the concrete ingredients and can be compared
to permeability. It has been recommended that for low permeability concrete, the sorptivity values should be less than
0.1mm3/mm2/√���[8]. The above comparisons show that the high performance concrete mixes developed in the present
investigation observed to have superior performance in the case of sorptivity.
Table: 5 Sorptivity results of HPC mix
0
0.5
1
1.5
2
2.5
3
3.528 days 90 days
Poro
sity
(%
)
% Replacement of MK + RHA
International Journal of Scientific Research and Review
Volume 7, Issue 2, 2018
ISSN NO: 2279-543X
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Mix Name RHA
(%)
MK
(%)
Sorptivity at 28 days
(mm/mm0.5)
Sorptivity at 90 days
(mm/mm0.5)
MC 0 0 0.052 0.043
M1 10 5 0.026 0.025
M2 10 7.5 0.025 0.020
M3 10 10 0.022 0.019
M4 12.5 5 0.019 0.017
M5 12.5 7.5 0.016 0.014
M6 12.5 10 0.021 0.019
M7 15 5 0.029 0.022
M8 15 7.5 0.032 0.026
M9 15 10 0.036 0.029
Fig: 9 Influence of MK and RHA on sorptivity of M60 mixes
7. CONCLUSIONS
7.1 Fresh and mechanical property of HPC mixes
The slump test result is carried to observe the workability of concrete, workability reduces as the MK and RHA content
increases. This is due to the increase in percentage of MK and RHA diminishes the water accessibility in the system,
thus affecting the workability, also due to the presence of High Pozzoloanic reactive nature of MK and RHA, liberating
Calcium Hydroxide.
7.2 Cube compressive strength
7.5+12.5% cement replaced concrete with MK and RHA is observed to be the optimum blend proportion to acquire M60
grade of HPC blends at the age of 28 Days.
The compression failure pattern of concrete is because of crushing of coarse aggregate and not due to bond failure.
The MK and RHA utilized in this investigation shows good pozzlonic properties, therefore, it is strongly recommended
for the production of HPC.
7.3 Saturated water absorption, Porosity and Sorptivity
Cement replacement level of 7.5+12.5 percent MK and RHA in concrete mixes is observed to be the optimum level. To
obtain lower value of saturated water absorption, porosity and sorptivity at the age of 28 days, the same result is
obtained at the age of 90 days also. It is examined that the mixes with 7.5+12.5 percent MK and RHA as cement
replacement material has the lowest value of saturated water absorption, porosity and sorptivity when contrasted with
concrete without MK and RHA.
ACKNOWLEDGMENT
I would like to express my profound sense of gratitude and appreciation to my guide Dr.S.Robert Ravi for his valuable
guidance, continuous encouragement and help rendered in carrying out the work presented in this report. I also extend
my special thanks to Dr.M.I.Abdul Aleem for spending his valuable and helpful suggestions to complete this work.
0
0.01
0.02
0.03
0.04
0.05
0.0628 days 90 days
Sorp
tivity (
mm
/mm
2)
% Replacement of MK+RHA
International Journal of Scientific Research and Review
Volume 7, Issue 2, 2018
ISSN NO: 2279-543X
http://dynamicpublisher.org/129
REFERENCES
[1] Aitcin P.C, ‘High Performance Concrete, E & FN Spon, London, (1998).
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concrete. Cement and Concrete research (1996).
[3] Kannan, V, Ganesan, K, ‘Strength and water absorption properties of ternary blended cement mortar using Rice Husk
ash and Metakaolin (2012).
[4] Bharath kumar B.H, Narayanan.R and Ramachandran D.S, ‘Mix proportioning of high performance concrete. Cement and
Concrete Composites (2001)
[5] Kadri E and Duval R, ‘Influence of Silica fume on the workability and compressive strength of High performance concrete,
cement and concrete research (1998)
[6] Sivakumar.M and Mahendran.N, ‘Strength and permeability properties of concrete using Fly ash, Rice husk ash and Egg
shell powder, Journal of Theoretical and Applied Information Technology, (2014)
[7] Zimbelman.R, ‘Contribution to the problem of cement aggregate bond. Cement and Concrete research, (1985)
[8] Razak, H, Chai, H.K. and Wong, H.S, ‘Near surface characteristics of concrete containing supplementary cementitious
materials, Cement and concrete composites, [2004]
[9] Speare, PRS, Eleftheriou, K, TG & Telford, T, ‘Durability of concrete containing Rice Husk Ash an additive, International
seminar on Exploiting Wastes in concrete, [1999]
[10] Kartini, K & Mahmud, ‘Absorption and permeability performance of Selangor Rice husk ash blended grade 30 concrete,
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[11] Malathy R and Subramanian K, ‘Role of mineral admixtures on the corrosion behavior of reinforcement in High
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[12] IS: 456-2000, ‘Indian Standard code of practice for plain and reinforced concrete
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BIOGRAPHIES
Swaminathen1 research scholar
Sree Sakthi Engineering College,
Tamil Nadu, India
Mail id: [email protected]
Robert Ravi2 Professor & Head
SSM Institute of Engineering and Technology
Tamil Nadu, India
Mail id: [email protected]
International Journal of Scientific Research and Review
Volume 7, Issue 2, 2018
ISSN NO: 2279-543X
http://dynamicpublisher.org/130