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ARPN Journal of Engineering and Applied
Sciences
April 2013 | Vol. 8 No. 4 |
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Title: |
Crushing
strength properties of furnace slag-fly ash blended lightweight
aggregates |
Author (s): |
P. Gomathi
and A. Sivakumar |
Abstract: |
Crushing strength of lightweight
aggregates depends on the efficiency of production, type of
binder used and size of the aggregate formed. Fly ash based
slag pellets were produced in the present study by
pelletization process. The pellets consist of fly ash and
furnace slag as binder substituted at 10%, 20% and 30% by the
weight of fly ash. A disc pelletizer was set to an angle of
36º with a speed of 55 rpm and pelletization duration of 10
minutes and 15 minutes was adopted. Hardening of cold bonded
fly ash aggregate was carried out in hot air oven at 100ºC.
The crushing strength of different size ranges of cold bonded
aggregate was tested at different ages. Test results showed
that the strength gain of pellet depends on the percentage of
binder added and pelletization duration. A significant
strength improvement is noticed at higher duration (15
minutes) (mix combination of 80% fly ash and 30% furnace slag
added with concentration of 10M of NaOH) compared to 10
minutes pelletization duration. Also, the strength reduction
was noticed with the increase in the size of pellets; due to
size effects. The crushing strength of smaller size pellets (6
mm diameter, 30G2) exhibited higher strength (43.88%) than the
larger size aggregate (16 mm diameter, 30G2) and a significant
reduction in strength was noted for bigger sized aggregates
due to size effect. |
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Title: |
Remaining
life assessment of damaged reinforced composites under inelastic
material behaviour |
Author (s): |
Dalbir Singh
and A Rajaraman |
Abstract: |
In this article, an
investigation on bi-directional carbon fiber composite INDCARF
manufactured in India - to study remaining life assessment-RLA-
of the composites to enable one to design suitably. But since
composites are made of different materials bonded and
reinforced with fibres, they develop distress in the form of
cracking and damage while in service and there is a need to
assess their performance in terms of strength and stiffness
for the remaining portion of their life. The cracking/damage
under different conditions is simulated in the form of
hair-line cracks, introduced on the surface of the coupons
used for testing. Based on coupon test results, analytical
studies using non-linear finite element model were carried out
to assess the influence of different characteristics of damage
on failure and remaining life. The cracking parameters were
identified as initiation, spread and inelastic material
behavior using elastic-plastic material model. The samples
were evaluated by tensile tests according to the ASTM D3039. |
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Title: |
Effect of the
lime content in marble powder for producing high strength
concrete |
Author (s): |
V. M.
Sounthararajan and A. Sivakumar |
Abstract: |
Marble powder is a by-product obtained during
the quarrying process from the parent marble rock; which
contains high calcium oxide content of more than 50%. The
potential use of marble dust can be an ideal choice for
substituting in cementitious binder as the reactivity
efficiency increases due to the presence of lime. In this
research work, the waste marble powder upto 10% (passing
through 45 microns) by weight of cement was investigated for
hardened concrete properties. Furthermore, the effect of
different percentage replacement of marble dust on the
compressive strength, splitting tensile strength and flexural
strength were evaluated. It can be noted that the influence of
fine to coarse aggregate ratio (F/C) and cement-to-total
aggregate ratio (C/TA) had higher influence on the improvement
in strength properties. A phenomenal increase in the
compressive strength of 46.80 MPa at 7 days for 10%
replacement of marble powder in cement content was noted and
also showed an improved mechanical property compared to
controlled concrete. |
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Title: |
A survey on
energy conservation techniques in wireless sensor networks |
Author (s): |
N.
Akilandeswari, B. Santhi and B. Baranidharan |
Abstract: |
In the last years, the research community and
actual users have enabled to increase the attention of
Wireless Sensor Networks. The lifetime of the sensor node is
based on battery powered devices. Several authors discussed
the different energy consumption techniques for different
layers. Consolidated efficient energy consumption techniques
are missing. This paper provides a detailed study about all
the existing energy conservation techniques and also explains
about limitations available in the techniques. In this paper,
the energy conservation approaches and its algorithms for
computing the optimal transmitting ranges in order to generate
a network with desired properties are discussed. Finally this
paper concludes with insights for research techniques about
energy conservation in Wireless Sensor Networks.
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Title: |
Untraditional
synthesis of Ni-based alloys for medical application |
Author (s): |
B.
Agyei-Tuffour, E. Annan, E. R. Rwenyagila, E. Ampaw, E. Arthur,
K. Mustapha, S. Kolawole, W. O. Soboyejo, M. I. Marinov and D. D. Radev |
Abstract: |
Due to the combination of
excellent mechanical properties, high chemical stability and
appropriate biocompatibility, the Ni-based alloys find large
application in implantology and dentistry. The traditional
metallurgical synthesis methods of these alloys have some
difficulties leading to inconstancy of the composition,
degradation of properties and escalation of the product price.
Here we show how to overcome the disadvantages of the
traditional methods of synthesis and production of Ni-based
alloys for medical application using combination of
mechanochemical and powder-metallurgical routes. The
structural properties of the products were studied using SEM/TEM
and XRD methods. It was shown that the mechanically assisted
synthesis allows obtaining nanosized Ni-Ti alloy with mean
particle size of 20-30 nm at significantly lower temperature
in comparison with the traditional metallurgical
high-temperature alloying. It was also shown that after 40
hours of intense mechanical treatment of the starting Ni and
Ti powders, a direct synthesis of Ni-Ti alloy proceeds. The
product has excellent sinterability which allows producing
bodies with controlled structural properties appropriate for
application in implantology. Using standard mechanical tests
and structural examinations it was demonstrated that the Ni-Cr
dental alloys obtained by mechanically assisted sintering and
casting possess excellent mechanical, technological and
aesthetic properties. These alloys are suitable as dental
restoration materials and production of porcelain veneered
constructions like crowns and bridges using the so called
metal-to-ceramic technique. |
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Title: |
Influence of
perforations on flexural strength of aluminium 8090alloy sheets |
Author (s): |
Venkatachalam G., Patel Nilay S.,
Neil P.M., Prafull Agarwal and Narayanan S. |
Abstract: |
Reliable knowledge about flexural strength of
sheet metals is very important for sheet metal bending
process. Young’s modulus and cross sectional area determine
the flexural strength of sheet metals. For perforated sheet
metals, the presence of holes reduces the cross sectional area
and hence the flexural strength is affected. In this paper, an
attempt is made to study the influence of presence of holes on
flexural strength of Aluminium 8090 alloy sheets. Experiments
are conducted to study the influence of hole size, percentage
of open area and hole arrangement pattern. |
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Title: |
Selective
assembly to minimize clearance variation in complex assemblies
using fuzzy evolutionary programming method |
Author (s): |
Jeevanantham A.K.
and Kannan S.M. |
Abstract: |
Selective
assembly is an economic method to obtain perfect precision
assemblies by using the components manufactured with wide
tolerance specifications. The mating component’s tolerances
are divided into equal number of groups. The manufactured
components are segregated according to these groups and the
components from the corresponding groups are assembled
interchangeably in the conventional method. The required
clearance can be achieved at this assembly method that is
tighter than those achieved at the normal fabrication method
with lowest total cost. Still there are more variations in the
clearance range. In this paper, a new optimization method is
proposed to find the best combination of the selective groups
to minimize assembly variation for the complex assemblies. A
case example is analyzed for piston, cylinder and piston ring
assembly. Fuzzy evolutionary programming (EP) method is used
to obtain the best combination of the selective groups to
control the assembly variation. Selective assembly is
successfully applied for a piston and cylinder assembly using
fuzzy EP method to achieve minimum clearance variation without
sacrificing the benefit of wider tolerance in manufacturing. |
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Title: |
Effect of
polythene modified bitumen on properties of hot mix asphalt |
Author (s): |
Mutiu Akinpelu,
Bamidele I. O. Dahunsi,
Oladipupo Olafusi,
Olufemi Awogboro and Adedeji Quadri |
Abstract: |
The continuous increase in road
traffic couple with an insufficient degree of maintenance due
to shortage of funds has caused an accelerated and continuous
deterioration of the road network in Nigeria. To alleviate
this process, several types of measures are reported to be
effective, for instance, securing funds for maintenance,
improved roadway design, use of better quality of materials
and the use of more effective construction methods. Improving
the quality of materials used in road construction had been
shown to improve road service performance in the wake of the
increase usage. Practical experiences over the last four
decades have shown that the modification of the bituminous
binder with polymer additives offers several benefits in
asphalt concrete and has been tested in a number of countries
around the World. The use of polythene materials for pure
water sachet in the country has received a great boost due to
its abundant supply and high resistance to insects, fungi,
animals, as well as molds, mildew, rot and many chemicals.
However the disposal of the waste polythene materials in large
quantities has been a problem all over the country. This study
was therefore designed to investigate the effect of polythene
as contained in pure water sachet in the asphalt concrete
properties. Polythene was added in grinded state as binder
modifier. It was introduced to the mixture by melting it in
the bitumen used in preparing the asphalt concrete mix.
Marshall Mix design method was used, first to determine the
optimum bitumen binder content and then further to test the
modified mixture properties. In total, 17 samples were
prepared (10 samples were used to determine the binder content
and the remaining samples were used to investigate the effect
of modifying the asphalt mixtures). The optimum asphalt
content was 7.0%. Six proportions of polyethylene by weight of
the optimum binder content were selected to be tested (2.5,
5.0, 7.5, 10, 12.5 and 15%). The properties tested include
bulk density, stability and flow of the concrete mix. The
obtained optimum proportion of the modifier is 12.5% by the
weight of the optimum bitumen content. It is found to increase
the stability, reduce the density and slightly reduce the flow
of asphalt concrete specimen. Findings from this study suggest
that polythene modifier offers better engineering properties
and its usage as bitumen modifier could serve as a means of
managing the waste menace. |
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Title: |
Study the
effect of externally and internally ply drop-off in composite
laminate analysis |
Author (s): |
Priyanka
Dhurvey and N. D. Mittal |
Abstract: |
Tapered
laminated structures, which are formed by dropping off some of
the plies at discrete positions over the laminate, have
received much attention from researchers because of their
structural tailoring capabilities, damage tolerance, and their
potential for creating significant weight savings in
engineering applications. The inherent weakness of this
construction is the presence of material and geometric
discontinuities at ply drop region that induce premature
interlaminar failure at interfaces between dropped and
continuous plies. In the present work the finite element
analysis of composite laminates with externally and internally
ply drop-off is presented. The effect of different lay-ups and
different ply drop-off ratio Th/L (where Th is total thickness
of ply drops and L is ply drop of length) under tensile load
is study. The finite element analysis is carried out using
ANSYS software. |
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Title: |
Study the effectiveness of the
different pozzolanic material on self-compacting concrete |
Author (s): |
Ahmed Fathi, Nasir Shafiq, M. F.
Nuruddin and Ali Elheber |
Abstract: |
This paper presents the study on
the effect of fly ash (FA), silica fume (SF) and microwave
incinerated rice husk ash (MIRHA) as cement replacement
material (CRM) on the mechanical and fresh properties of
self-compacting Concrete (SCC). Some of the CRM materials are
supposed to enhance the properties of SCC by avoiding the
Bleeding at fresh stage and increase the strength in the long
term at hardened stage, in addition of that CRM can reduce
the total cost of mixing depends on the replacement percentage. The experimental work included the workability test as well
as mechanical test of SCC. Workability test determined the
flowability, filling ability and segregation resistance by
slump flow, slump T50, L-box and V-funnel testes. The
mechanical properties by applying compressive strength,
splitting tensile strength and flexural strength were
investigated. There were a total of nine mixes created with
different CRM contents. The result showed that the MIRHA
needded more water as compared to SF to achieve the similar
fresh properties, similarly concrete with 5% SF showed about
9.70% highest compressive strength after 90 days, 5.10 MPa
high tensile strength and 10.12 MPa flexural strength when
compared with other mixes. |
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Title: |
Experimental
study of combined oblique weir and gate structure |
Author (s): |
Shaker A. Jalil and Sarhan
Abdulsatar Sarhan |
Abstract: |
Flow measurement in open channel
is important to support the system management. An experimental
study in a laboratory flume is carried out to study flow over a
sharp crested weir and under gate in combined structure as
flow measurement device. Four different oblique angles to the
longitudinal axis of the channel and four different heights of
gate opening were used. The basic principles of statistical
analysis are employed to correlate between the hydraulic and
geometric dimensionless parameters with the discharge
coefficient. Different relationship models with acceptable
significance are suggested. It was found that the major
parameters effecting significantly on discharge coefficient
are (h/d, α, L/d, P/d), and value of Cd range from
0.623 to 0.403, with Standard Error 0.0047. Within the
limitations of the present experimental work two different
discharge equations were predicted. The first equation Which
assumed that the coefficient of discharge is the same for weir
and gate with R2 of o.972, and the second which
assumed that there is different percent of discharge for each
weir and gate with R2 of 0.997. |
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