International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2014
Analytical Study of Light Weight Concrete by
using juniper bark as a partial replacement of
coarse aggregate
R. Praba Rajathi, J. John Bosco

Abstract—Concrete is the widely used building material in the
world. Juniper bark has been the most popular choice for
coarse aggregate in concrete. Light weight concrete is a type of
concrete which includes an expanding agent in that it increases
the volume of the mixture & lighter than the conventional
concrete. The alligator juniper is named for its distinctive bark
that resembles the rough, checked skin of an alligator. This
species can either be shrub or tree depending on the growing
location and conditions. The aim of this present work is to
investigate the possibility of partially replacement of coarse
aggregate in concrete by adding juniper bark and evaluate its
compressive, split tensile and flexural strength. This research
work examines the effect of juniper bark and the properties of
concrete and compares with the conventional concrete. The
main objective of this thesis is to decrease the weight of concrete
by partially replace the aggregate by adding juniper bark and
also improve the compaction and durability of light weight
concrete by using admixture like silica fume.
Index Terms— Normal concrete, light weight concrete, juniper
bark, silica fume.
I. INTRODUCTION
Concrete is one of the most versatile building
materials. It can be cast to fit in any structural shape. It is
readily available in urban areas at relatively low cost.
Concrete is strong under compression yet weak under tension
and a relatively brittle material. As such, a form of
reinforcement is needed. Concrete is made from a mixture of
cement powder, coarse & fine aggregates.
Lightweight concrete can be defined as a type of
concrete which giving lessened the deadweight. It is lighter
than the conventional concrete. The main specialities of
lightweight concrete are its low density and thermal
conductivity. Light weight concrete is concrete weighing
substantially less than that made using gravel or crushed
stone aggregates. This loose definition is generally agreed to
cover a broad spectrum of concretes ranging in weight from
12 to 120 pounds per cubic feet [1].
Manuscript received Dec20, 2014.
RPrabaRajathi.,
CivilEngineering
Department,
A.S.L.
PaulsCollegeofEngineering&Technology,,(v.prabarajathi@gamil.com).
Coimbatore, TamilNadu,India, Mobile No9788676655,J.JohnBosco, Civil
EngineeringDepartment, A.S.L. PaulsCollegeofEngineering&Technology,
Coimbatore,
TamilNadu,India,
Mobile
No7639520233(e-mail:
johnymtech@gmail.com).
The use of structural grade light weight concrete
reduced considerably the self load of a structure and permit
larger precast units to be handled. The water absorption of
the green aggregate is large but the crushing strength of the
resulting concrete can be high [2].
Cellular concrete is being used in a wide variety of
applications because of its light weight, insulating, fire
resistant, chemical resistant and structural properties.
Cellular concrete is more durable when compared to
traditional insulating materials [3]. The strength
characteristics of concrete containing periwinkle cells have
been indicated as adequate for construction works. Light
weight concrete containing periwinkle cells as aggregate can
also be exposed to temperature variation due to fire/ heat
during its life time expectancy [4].
A parametric
experimental study which investigates the potential use of
wood saw waste – limestone powder waste combination for
producing a low cost and light weight composite as a building
material [5].
At 30% wood saw waste replacement with limestone
powder waste in the brick sample the thermal conductivity
value is effectively reduced and the reduction in the thermal
conductivity value of brick sample at 30% wood saw waste
replacement with lime stone powder waste is about 38.9% as
compared with control sample [6]. The compressive
strength, elastic modulus, splitting tensile strength, specific
creep and other properties of light weight concrete are
significantly affected by the structural properties of the light
weight aggregate used [7]. The loss of compressive strength
with only 25% bark indicates that the bark, as received from
the field, is not be compatible with producing quality
concrete. Examination of the post-test specimens suggests
that a reduction of the hydration process may be occurring
with an increase in wood fibres [8].
Lightweight
Construction Methods (LCM) (also known as foam concrete
(FC)/cellular lightweight concrete (CLWC)) were developed
more than 60 years ago and since then have been used
internationally for different construction applications. LCM
has been used in the building industry for applications such as
apartments, houses, schools, hospitals, and commercial
buildings [9]. In order to reach target slump and air content,
fewer amounts of chemical admixtures was used in
lightweight concretes than in normal-weight concrete,
leading to reduction in production cost. The use of
lightweight aggregates (LWA) instead of normal weight
aggregates in concrete production slightly decreased the
strength. The models given by codes, standards and software
and equation derived in this study gave close estimated
values to the experimental results [10].This paper deals with
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All Rights Reserved © 2012 IJSETR
International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2012
the use of juniper bark as a partial replacement for coarse
aggregate to produce light weight concrete (LWC) and
compare the result of this light weight concrete with the
conventional concrete. By adding the admixture like silica
fumes with the concrete for increase the compressive strength
and also increases durability of concrete.
II. METHODOLOGY
A. Methods
The concrete mix made from the mixture of cement,
fine & coarse aggregate and water as per the mix design. The
following procedure used for making the concrete specimens.
 9 Specimens with 5% juniper bark
 3 Cubes with the size of 150mm X
150mm X 150mm
 3 cylinders with the size of 150mm
dia and 300mm height
 3 prisms with the size of 500mm X
100mm X 100mm
 9 specimens with 10% juniper bark (3 Cubes,
3 cylinders, 3 prisms)
 3 Cubes , 3 cylinders & 3 prisms
with same size as mentioned above
 9 specimens with 0% juniper bark
(conventional concrete) (3 Cubes, 3
cylinders, 3 prisms)
 3 Cubes , 3 cylinders & 3 prisms
with same size as mentioned above
After moulding of specimens, tests were carried out for
7days, 14 days and 28 days for each specimen in the
laboratory. Then analyse the test results for compressive
strength, split tensile strength & flexural strength of light
weight concrete with conventional concrete.
III. MATERIALS
A. Cement
Ordinary Portland Cement (OPC) of 53 grade was
used as the main cementing material. The cement was tested
for fineness, specific gravity, setting time, compressive
strength, consistency and the results were shown on below
Table –I.
Table I: TESTS ON CEMENT
Sl. No.
Properties of cement
Value
1.
Fineness
220(m2/kg)
2.
specific gravity
3.10
3.
Initial setting time
33 min
4.
Final setting time
2hrs
5.
compressive strength (7 days)
35 N/mm2
6.
compressive strength ( 14
days)
46 N/mm2
7.
compressive strength (28 days)
51 N/mm2
8.
Consistency
31%
B. Fine Aggregate
Locally available sand in the form of natural pit sand by
source was used as the fine aggregate (FA). The sand was
found as deposits in soil, obtained by forming pits into the
soil. The physical properties of fine aggregate were shown in
table- II.
Table II: TESTS ON FINE AGGREGATE
Sl.
No.
Properties of Fine aggregate
Value
1.
Fineness modulus
2.72
2.
Specific gravity
2.61
3.
Bulk density – loose
1588 Kg/m3
4.
Bulk density – compact
1686 Kg/m3
C. Coarse Aggregate
Aggregates were first considered to simply be filler for
concrete to reduce the amount of cement required. However,
it is now known that the type of aggregate used for concrete
can have considerable effects on the plastic and hardened
state properties of concrete. The coarse aggregate of 12.5mm
maximum size rounded obtained from the local nearby area is
used in the present study. The physical properties of coarse
aggregate like specific gravity, bulk density, gradation and
fineness modulus are tested in accordance with IS:2386.
Table III: TESTS ON FINE AGGREGATE
Sl. No.
Properties of Coarse
aggregate
Value
1.
Fineness modulus
6.15
2.
Specific gravity
2.62
3.
Bulk density – loose
1470 Kg/m3
4.
Bulk density – compact
1685 Kg/m3
D. Juniper Bark
The juniper bark tree is having many types. The
Alligator juniper is one of the types of this bark and it is used
for the present study due to its physical appearance like
coarse aggregate. The Alligator juniper is named for its
distinctive bark that resembles the rough, checked skin of an
alligator. This species can either be a shrub or tree depending
on the growing location and conditions. This is a member of
the cypress family. The tree is easily identified by its bark,
which becomes deeply fissured with age to form squares 1 to
2 inches on a side.
E. Silica Fumes
Very fine non-crystalline silica produced in electric
arc furnaces as a by-product of the production of elemental
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All Rights Reserved © 2012 IJSETR
International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2014
Split tensile strength of
cylinders
silicon or alloys containing silicon also known as condensed
silica fume or micro silica. In Silica fume, silicon dioxide has
presented more than 85%. Silica fume has specific surface
area of about 20000m2/kg as against 230 to 300m2/kg that of
cement. The properties of silica fume is shown in table -IV
Table IV: PROPERTIES OF SILICA FUME
Properties of Silica fume
Value
1.
Particle size
<1µm
2.
Specific gravity
2.4
3.
Bulk density – slurry
1378 Kg/m3
4.
Bulk density – densified
584 Kg/m3
5.
Surface area
13000 to
30000m2/kg
IV. MIX DESIGN
The following mix proportion is used for making concrete
specimen in this present study.
1: 2.9: 3.2: 0.61
Compressive strength of cube
specimens
50
40
30
7 DAY
20
14 DAY
10
28 DAY
0
0%
5%
10% 15%
Concrete with % of juniper bark - specimens
Fig. 1 Compressive strength of concrete cubes
Fig.1 shows that the increase in the percentage of juniper
bark has proportionate increase in compressive strength up to
10% for all the days, for percentage above 10%, the
compressive strength decreases.
4
7 DAY
2
14 DAY
0
0%
5%
10%
15%
28 DAY
Fig. 2 Split tensile strength of cylinders
Fig. 2 shows that the increase in the percentage of juniper
bark has proportionate increase in split tensile strength up to
10% for all the days, for percentage above 10%, the split
tensile strength decreases.
F. Water
The water which is used for making concrete should
be cleaned and free from harmful impurities such as oil,
alkali, acid etc. In general the water which is fit for drinking
should be used for making concrete.
V. RESULTS AND DISCUSSIONS
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Concrete with % of juniper bark - specimens
Flexural strength of prisms
Sl.
No.
8
5
4
3
2
1
0
7 DAY
14 DAY
28 DAY
0%
5%
10%
15%
Concrete with % of juniper bark - specimens
Fig. 3 Flexural strength of prisms
Fig.3 shows that the increase in the percentage of
juniper bark has proportionate increase in flexural strength up
to 10% for all the days, for percentage above 10%, the
flexural strength decreases.
The optimum replacement level of coarse aggregate by
juniper bark is obtained as 10% from the experiments. From
the comparison with the conventional concrete, 10% juniper
bark used concrete showed significant increment in strength
for all specimens.
IV. CONCLUSION
The study on the compressive, split tensile and flexural
strength of juniper bark used concrete revealed the optimum
replacement of coarse aggregate by juniper bark as 10%. The
juniper bark along with silica fume can be effectively used in
concrete for construction work. This concrete is said to be
eco-friendly concrete because of using juniper bark as a
replacement material in concrete.
REFERENCES
[1]
[2]
[3]
Deepika B., “Behavioural study of light weight concrete in structural
element,” International journal of science and engineering research,
vol. 2, issue 9, pp. 1-4, Sep 2014.
Tommy Y. Low and Cui H.Z., “Properties of green light weight
aggregate concrete,” International workshop on sustainable
development and concrete technology, pp. 113-118.
B. Dolton and C. Hannah, “Cellular concrete: Engineering and
Technological Advancement for construction in cold climates”, The
2006 Annual general conference of the Canadian society for civil
engineering, Calgary, Alberta, Canada, pp- 125(1) – 125 (11), May
2006.
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All Rights Reserved © 2012 IJSETR
International Journal of Science, Engineering and Technology Research (IJSETR)
Volume 1, Issue 1, July 2012
Falade F., E.E. Ikponmwosa and N.I. Ojediran, “Behaviour of light
weight concrete containing periwinkle cells at elevated temperature”,
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379-390, 2010.
[5] Paki Turgut, Halimurut, “Limestone dust and wood saw dust as brick
material”, Elesevier, Building and Environment, Vol 42, pp.
3801-3807, 2007.
[6] Park Turgut and Mehmet Gumuscu, “Thermo-Elastic properties of
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no. 4, pp. 128-132. 2013.
[7] Kenneth S. and Harmon P.E., “Engineering Properties of structural
light weight concrete”, pp. 2-11, US.
[8] Michael A. and Cornachione P.E., Juniper bark as aggregate substitute
in concrete, Research book, Winema national forest, 2819, Dahlia
street, Klamath falls, Oregon.
[9] Mazhar Ul haq and Alex liew, “Light weight/low cost construction
methods for Developing countries”, CBM-CI International
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[10] Niyazi Ugur Kockal and Turan Ozturan , “Strength and elastic
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[4]
R. Praba Rajathi is now working as an assistant
professor in A.S.L.Pauls College of Engineering & Technology,
Coimbatore. She completed her B.E. (Civil) in Thiagarajar College of
Engineering, Madurai (2003). She completed her M.E. (Env. Engg.) in
Government College of Technology, Coimbatore (2009). She has published
several journals regarding Concrete technology, Environmental
Engineering, etc.
J. John Bosco is now working as an assistant
professor in A.S.L. Pauls college of engineering and technology,
Coimbatore. He completed his B.Sc. (geography) in Bharathiyar university
arts and science college, Gudalur, Nilgris. He completed his M.Sc. (applied
geography) in Government arts college, Coimbatore. He completed his
M.Tech(Geology) in Bharathidasan university, Trichy.
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