Abstract: This paper investigates the effectiveness of the use of
seismic isolation devices on the overall 3D seismic response of
curved highway viaducts with an emphasis on expansion joints.
Furthermore, an evaluation of the effectiveness of the use of cable
restrainers is presented. For this purpose, the bridge seismic
performance has been evaluated on four different radii of curvature,
considering two cases: restrained and unrestrained curved viaducts.
Depending on the radius of curvature, three-dimensional non-linear
dynamic analysis shows the vulnerability of curved viaducts to
pounding and deck unseating damage. In this study, the efficiency of
using LRB supports combined with cable restrainers on curved
viaducts is demonstrated, not only by reducing in all cases the
possible damage, but also by providing a similar behavior in the
viaducts despite of curvature radius.
Abstract: Soil stabilization has been widely used to improve
soil strength and durability or to prevent erosion and dust generation.
Generally to reduce problems of clayey soils in engineering work and
to stabilize these soils additional materials are used. The most
common materials are lime, fly ash and cement. Using this materials,
although improve soil property , but in some cases due to financial
problems and the need to use special equipment are limited .One of
the best methods for stabilization clayey soils is neutralization the
clay particles. For this purpose we can use ion exchange materials.
Ion exchange solution like CBR plus can be used for soil
stabilization. One of the most important things in using CBR plus is
determination the amount of this solution for various soils with
different properties. In this study a laboratory experiment is conduct
to evaluate the ion exchange capacity of three soils with various
plasticity index (PI) to determine amount or required CBR plus
solution for soil stabilization.
Abstract: Cameron Highlands is known for upland tourism area
with vast natural wealth, mountainous landscape endowed with rich
diverse species as well as people traditions and cultures. With these
various resources, CH possesses an interesting visual and panorama
that can be offered to the tourist. However this benefit may not be
utilized without obtaining the understanding of existing landscape
structure and visual. Given a limited data, this paper attempts to
classify landscape visual of Cameron Highlands using land use and
contour data. Visual points of view were determined from the given
tourist attraction points in the CH Local Plan 2003-2015. The result
shows landscape visual and structure categories offered in the study
area. The result can be used for further analysis to determine the best
alternative tourist trails for tourism planning and decision making
using readily available data.
Abstract: The new optimization method for fiber orientation
angle optimization of symmetrical multilayer plates like plywood is
proposed. Optimization method consists of seeking for minimal
compliance by choosing appropriate fiber orientation angle in outer
layers of flexural plate. The discrete values of fiber orientation angles
are used in method. Optimization results of simply supported plate
and multispan plate with uniformly distributed load are provided.
Results show that stiffness could be increased up to 20% by changing
wood fiber orientation angle in one or two outer layers.
Abstract: Basic objective of this study is to create a regression
analysis method that can estimate the length of a plastic hinge which
is an important design parameter, by making use of the outcomes of
(lateral load-lateral displacement hysteretic curves) the experimental
studies conducted for the reinforced square concrete columns. For
this aim, 170 different square reinforced concrete column tests results
have been collected from the existing literature. The parameters
which are thought affecting the plastic hinge length such as crosssection
properties, features of material used, axial loading level,
confinement of the column, longitudinal reinforcement bars in the
columns etc. have been obtained from these 170 different square
reinforced concrete column tests. In the study, when determining the
length of plastic hinge, using the experimental test results, a
regression analysis have been separately tested and compared with
each other. In addition, the outcome of mentioned methods on
determination of plastic hinge length of the reinforced concrete
columns has been compared to other methods available in the
literature.
Abstract: The main aim of this research is to study the possible
use of recycled fine aggregate made from waste rubble wall to
substitute partially for the natural sand used in the production of
cement and sand bricks. The bricks specimens were prepared by
using 100% natural sand; they were then replaced by recycled fine
aggregate at 25, 50, 75, and 100% by weight of natural sand. A series
of tests was carried out to study the effect of using recycled aggregate
on the physical and mechanical properties of bricks, such as density,
drying shrinkage, water absorption characteristic, compressive and
flexural strength. Test results indicate that it is possible to
manufacture bricks containing recycled fine aggregate with good
characteristics that are similar in physical and mechanical properties
to those of bricks with natural aggregate, provided that the percentage
of recycled fine aggregates is limited up to 50-75%.
Abstract: Seismic qualification testing for equipments to be
mounted on upper storeys of buildings is very demanding in terms of
floor spectra. The latter is characterized by high accelerations
amplitudes within a narrow frequency band. This article presents a
method which permits to cover specified required response spectra
beyond the shaking table capability by amplifying the acceleration
amplitudes at an appropriate frequency range using a physical
intermediate mounted on the platform of the shaker.
Abstract: The Bangalore City is facing the acute problem of
pollution in the atmosphere due to the heavy increase in the traffic
and developmental activities in recent years. The present study is an
attempt in the direction to assess trend of the ambient air quality
status of three stations, viz., AMCO Batteries Factory, Mysore Road,
GRAPHITE INDIA FACTORY, KHB Industrial Area, Whitefield
and Ananda Rao Circle, Gandhinagar with respect to some of the
major criteria pollutants such as Total Suspended particular matter
(SPM), Oxides of nitrogen (NOx), and Oxides of sulphur (SO2). The
sites are representative of various kinds of growths viz., commercial,
residential and industrial, prevailing in Bangalore, which are
contributing to air pollution. The concentration of Sulphur Dioxide
(SO2) at all locations showed a falling trend due to use of refined
petrol and diesel in the recent years. The concentration of Oxides of
nitrogen (NOx) showed an increasing trend but was within the
permissible limits. The concentration of the Suspended particular
matter (SPM) showed the mixed trend. The correlation between
model and observed values is found to vary from 0.4 to 0.7 for SO2,
0.45 to 0.65 for NOx and 0.4 to 0.6 for SPM. About 80% of data is
observed to fall within the error band of ±50%. Forecast test for the
best fit models showed the same trend as actual values in most of the
cases. However, the deviation observed in few cases could be
attributed to change in quality of petro products, increase in the
volume of traffic, introduction of LPG as fuel in many types of
automobiles, poor condition of roads, prevailing meteorological
conditions, etc.
Abstract: Firstly, this study briefly presents the current situation that there exists a vast gap between current Chinese and Japanese seismic design specification for bridge pile foundation in liquefiable and liquefaction-induced lateral spreading ground; The Chinese and Japanese seismic design method and technical detail for bridge pile foundation in liquefying and lateral spreading ground are described and compared systematically and comprehensively, the methods of determining coefficient of subgrade reaction and its reduction factor as well as the computing mode of the applied force on pile foundation due to liquefaction-induced lateral spreading soil in Japanese design specification are especially introduced. Subsequently, the comparison indicates that the content of Chinese seismic design specification for bridge pile foundation in liquefiable and liquefaction-induced lateral spreading ground, just presenting some qualitative items, is too general and lacks systematicness and maneuverability. Finally, some defects of seismic design specification in China are summarized, so the improvement and revision of specification in the field turns out to be imperative for China, some key problems of current Chinese specifications are generalized and the corresponding improvement suggestions are proposed.
Abstract: To date, theoretical studies concerning the Carbon
Fiber Reinforced Polymer (CFRP) strengthening of RC beams with
openings have been rather limited. In addition, various numerical
analyses presented so far have effectively simulated the behaviour of
solid beam strengthened by FRP material. In this paper, a two
dimensional nonlinear finite element analysis is presented to validate
against the laboratory test results of six RC beams. All beams had the
same rectangular cross-section geometry and were loaded under four
point bending. The crack pattern results of the finite element model
show good agreement with the crack pattern of the experimental
beams. The load midspan deflection curves of the finite element
models exhibited a stiffer result compared to the experimental beams.
The possible reason may be due to the perfect bond assumption used
between the concrete and steel reinforcement.
Abstract: The purpose of this paper is to investigate the
durability of cement mortar in presence of Rice Husk Ash (RHA).
The strength and durability of mortar with different replacement
level (0%, 10%, 15%, 20%, 25% and 30%) of Ordinary Portland
Cement (OPC) by RHA is investigated here. RHA was
manufactured from an uncontrolled burning process. Test samples
were prepared with river sand of FM 2.73. Samples were kept in
controlled environment up to test time. The results show that
addition of RHA was shown better results for 20% replacement
level than OPC at 90 days. In durability test all samples passed for
20 cycles except 25% and 30% replacement level.
Abstract: There has been gradual progress of late in construction projects, particularly in big-scale megaprojects. Due to the long-term construction period, however, with large-scale budget investment, lack of construction management technologies, and increase in the incomplete elements of project schedule management, a plan to conduct efficient operations and to ensure business safety is required. In particular, as the project management information system (PMIS) is meant for managing a single project centering on the construction phase, there is a limitation in the management of program-scale businesses like megaprojects. Thus, a program management information system (PgMIS) that includes program-level management technologies is needed to manage multiple projects. In this study, a support tool was developed for managing the cost and schedule information occurring in the construction phase, at the program level. In addition, a case study on the developed support tool was conducted to verify the usability of the system. With the use of the developed support tool program, construction managers can monitor the progress of the entire project and of the individual subprojects in real time.
Abstract: Though nonlinear dynamic analysis using a specialized
hydro-code such as AUTODYN is accurate and useful tool for
progressive collapse assessment of a multi-story building subjected to
blast load, it takes too much time to be applied to a practical simulation
of progressive collapse of a tall building. In this paper, blast analysis of
a RC frame structure using a simplified model with Reinforcement
Contact technique provided in Ansys Workbench was introduced and
investigated on its accuracy. Even though the simplified model has a
fraction of elements of the detailed model, the simplified model with
this modeling technique shows similar structural behavior under the
blast load to the detailed model. The proposed modeling method can
be effectively applied to blast loading progressive collapse analysis of
a RC frame structure.
Abstract: Sampling and analysis of leachate from Bhalaswa
landfill and groundwater samples from nearby locations, clearly
indicated the likely contamination of groundwater due to landfill
leachate. The results of simulation studies carried out for the
migration of Chloride from landfill shows that the simulation results
are in consonance with the observed concentration of Chloride in the
vicinity of landfill facility. The solid waste disposal system presently
being practiced in Delhi consists of mere dumping of wastes
generated, at three locations Bhalaswa, Ghazipur, and Okhla without
any regard to proper care for the protection of surrounding
environment. Bhalaswa landfill site in Delhi, which is being operated
as a dump site, is expected to become cause of serious groundwater
pollution in its vicinity. The leachate from Bhalaswa landfill was
found to be having a high concentration of chlorides, as well as DOC,
COD. The present study was undertaken to determine the likely
concentrations of principle contaminants in the groundwater over a
period of time due to the discharge of such contaminants from
landfill leachates to the underlying groundwater. The observed
concentration of chlorides in the groundwater within 75m of the
radius of landfill facility was found to be in consonance with the
simulated concentration of chloride in groundwater considering one
dimensional transport model, with finite mass of contaminant source.
Governing equation of contaminant transport involving advection and
diffusion-dispersion was solved in matlab7.0 using finite difference
method.
Abstract: The commercial finite element program LS-DYNA was employed to evaluate the response and energy absorbing capacity of cylindrical metal tubes that are externally wrapped with composite. The effects of composite wall thickness, loading conditions and fiber ply orientation were examined. The results demonstrate that a wrapped composite can be utilized effectively to enhance the crushing characteristics and energy absorbing capacity of the tubes. Increasing the thickness of the composite increases the mean force and the specific energy absorption under both static and dynamic crushing. The ply pattern affects the energy absorption capacity and the failure mode of the metal tube and the composite material property is also significant in determining energy absorption efficiency.
Abstract: Load balancing is the process of improving the
performance of a parallel and distributed system through a
redistribution of load among the processors [1] [5]. In this paper we
present the performance analysis of various load balancing
algorithms based on different parameters, considering two typical
load balancing approaches static and dynamic. The analysis indicates
that static and dynamic both types of algorithm can have
advancements as well as weaknesses over each other. Deciding type
of algorithm to be implemented will be based on type of parallel
applications to solve. The main purpose of this paper is to help in
design of new algorithms in future by studying the behavior of
various existing algorithms.
Abstract: In the present work, behavior of inoxydable steel as
reinforcement bar in composite concrete is being investigated. The
bar-concrete adherence in reinforced concrete (RC) beam is studied
and focus is made on the tension stiffening parameter. This study
highlighted an approach to observe this interaction behavior in
bending test instead of direct tension as per reported in many
references. The approach resembles actual loading condition of the
structural RC beam. The tension stiffening properties are then
applied to numerical finite element analysis (FEA) to verify their
correlation with laboratory results. Comparison with laboratory
shows a good correlation between the two. The experimental settings
is able to determine tension stiffening parameters in RC beam and
the modeling strategies made in ABAQUS can closely represent the
actual condition. Tension stiffening model used can represent the
interaction properties between inoxydable steel and concrete.
Abstract: Dust storms are one of the most costly and destructive
events in many desert regions. They can cause massive damages both
in natural environments and human lives. This paper is aimed at
presenting a preliminary study on dust storms, as a major natural
hazard in arid and semi-arid regions. As a case study, dust storm
events occurred in Zabol city located in Sistan Region of Iran was
analyzed to diagnose and predict dust storms. The identification and
prediction of dust storm events could have significant impacts on
damages reduction. Present models for this purpose are complicated
and not appropriate for many areas with poor-data environments. The
present study explores Gamma test for identifying inputs of ANNs
model, for dust storm prediction. Results indicate that more attempts
must be carried out concerning dust storms identification and
segregate between various dust storm types.
Abstract: Over half of the total electricity consumption is used in buildings. Air-conditioning and electric lighting are the two main resources of electricity consumption in high rise buildings. One way to reduce electricity consumption would be to limit heat gain into buildings, therefore reduce the demand for air-conditioning during hot summer months especially in hot regions. On the other hand natural daylight can be used to reduce the use of electricity for artificial lighting. In this paper effective factors on minimizing heat gain and achieving required day light were reviewed .As daylight always accompanied by solar heat gain. Also interactions between heat gain and daylight were discussed through previous studies and equations which are related to heat gain and day lighting especially in high rise buildings. As a result importance of building-s form and its component on energy consumption in buildings were clarified.
Abstract: Heterogeneity of solid waste characteristics as well as the complex processes taking place within the landfill ecosystem motivated the implementation of soft computing methodologies such as artificial neural networks (ANN), fuzzy logic (FL), and their combination. The present work uses a hybrid ANN-FL model that employs knowledge-based FL to describe the process qualitatively and implements the learning algorithm of ANN to optimize model parameters. The model was developed to simulate and predict the landfill gas production at a given time based on operational parameters. The experimental data used were compiled from lab-scale experiment that involved various operating scenarios. The developed model was validated and statistically analyzed using F-test, linear regression between actual and predicted data, and mean squared error measures. Overall, the simulated landfill gas production rates demonstrated reasonable agreement with actual data. The discussion focused on the effect of the size of training datasets and number of training epochs.