Abstract: This paper presents the use of three-dimensional finite
elements coupled with infinite elements to investigate the ground
vibrations at the surface in terms of the peak particle velocity (PPV)
due to construction of the first bore of the Dublin Port Tunnel. This
situation is analysed using a commercially available general-purpose
finite element package ABAQUS. A series of parametric studies is
carried out to examine the sensitivity of the predicted vibrations to
variations in the various input parameters required by finite element
method, including the stiffness and the damping of ground. The
results of this study show that stiffness has a more significant effect
on the PPV rather than the damping of the ground.
Abstract: Behavior of dams against the seismic loads has been
studied by many researchers. Most of them proposed new numerical
methods to investigate the dam safety. In this paper, to study the
effect of nonlinear parameters of concrete in gravity dams, a twodimensional
approach was used including the finite element method,
staggered method and smeared crack approach. Effective parameters
in the models are physical properties of concrete such as modulus of
elasticity, tensile strength and specific fracture energy. Two different
models were used in foundation (mass-less and massed) in order to
determine the seismic response of concrete gravity dams. Results
show that when the nonlinear analysis includes the dam- foundation
interaction, the foundation-s mass, flexibility and radiation damping
are important in gravity dam-s response.
Abstract: Water level forecasting using records of past time series is of importance in water resources engineering and management. For example, water level affects groundwater tables in low-lying coastal areas, as well as hydrological regimes of some coastal rivers. Then, a reliable prediction of sea-level variations is required in coastal engineering and hydrologic studies. During the past two decades, the approaches based on the Genetic Programming (GP) and Artificial Neural Networks (ANN) were developed. In the present study, the GP is used to forecast daily water level variations for a set of time intervals using observed water levels. The measurements from a single tide gauge at Urmia Lake, Northwest Iran, were used to train and validate the GP approach for the period from January 1997 to July 2008. Statistics, the root mean square error and correlation coefficient, are used to verify model by comparing with a corresponding outputs from Artificial Neural Network model. The results show that both these artificial intelligence methodologies are satisfactory and can be considered as alternatives to the conventional harmonic analysis.
Abstract: Renewable energy systems are becoming a topic of
great interest and investment in the world. In recent years wind
power generation has experienced a very fast development in the
whole world. For planning and successful implementations of good
wind power plant projects, wind potential measurements are
required. In these projects, of great importance is the effective choice
of the micro location for wind potential measurements, installation of
the measurement station with the appropriate measuring equipment,
its maintenance and analysis of the gained data on wind potential
characteristics. In this paper, a wavelet transform has been applied to
analyze the wind speed data in the context of insight in the
characteristics of the wind and the selection of suitable locations that
could be the subject of a wind farm construction. This approach
shows that it can be a useful tool in investigation of wind potential.
Abstract: Membrane distillation (MD) is a rising technology for
seawater or brine desalination process. In this work, an air gap
membrane distillation (AGMD) performance was investigated for
aqueous NaCl solution along with natural ground water and seawater.
In order to enhance the performance of the AGMD process in
desalination, that is, to get more flux, it is necessary to study the
effect of operating parameters on the yield of distillate water. The
influence of operational parameters such as feed flow rate, feed
temperature, feed salt concentration, coolant temperature and air gap
thickness on the membrane distillation (MD) permeation flux have
been investigated for low and high salt solution. the natural
application of ground water and seawater over 90 h continuous
operation, scale deposits observed on the membrane surface and
reduction in flux represents 23% for ground water and 60% for
seawater, in 90 h. This reduction was eliminated (less than 14 %) by
acidification of feed water. Hence, promote the research attention in
apply of AGMD for the ground water as well as seawater
desalination over today-s conventional RO operation.
Abstract: Most often the contaminants are not taken seriously into consideration, and this behavior comes out directly from the lack of monitoring and professional reporting about pollution in the printing facilities in Serbia. The goal of planned and systematic ozone measurements in ambient air of the screen printing facilities in Novi Sad is to examine of its impact on the employees health, and to track trends in concentration. In this study, ozone concentrations were determined by using discontinuous and continuous method during the automatic and manual screen printing process. Obtained results indicates that the average concentrations of ozone measured during the automatic process were almost 3 to 28 times higher for discontinuous and 10 times higher for continuous method (1.028 ppm) compared to the values prescribed by OSHA. In the manual process, average concentrations of ozone were within prescribed values for discontinuous and almost 3 times higher for continuous method (0.299 ppm).
Abstract: The research investigates the effects of super plasticizer and molarity of sodium hydroxide alkaline solution on the workability, microstructure and compressive strength of self compacting geopolymer concrete (SCGC). SCGC is an improved way of concreting execution that does not require compaction and is made by complete elimination of ordinary Portland cement content. The parameters studied were superplasticizer (SP) dosage and molarity of NaOH solution. SCGC were synthesized from low calcium fly ash, activated by combinations of sodium hydroxide and sodium silicate solutions, and by incorporation of superplasticizer for self compactability. The workability properties such as filling ability, passing ability and resistance to segregation were assessed using slump flow, T-50, V-funnel, L-Box and J-ring test methods. It was found that the essential workability requirements for self compactability according to EFNARC were satisfied. Results showed that the workability and compressive strength improved with the increase in superplasticizer dosage. An increase in strength and a decrease in workability of these concrete samples were observed with the increase in molarity of NaOH solution from 8M to 14M. Improvement of interfacial transition zone (ITZ) and micro structure with the increase of SP and increase of concentration from 8M to 12M were also identified.
Abstract: Typically thermal power plants are located near to
surface coal mines that produce huge amount of fly ash as a waste
byproduct. Disposal of fly ash causes significant economic and
environmental problems. Now-a-days, research is going on for bulk
utilization of fly ash. In order to increase its percentage utilization, an
investigation was carried out to evaluate its potential for haul road
construction. This paper presents the laboratory California bearing
ratio (CBR) tests and evaluates the effect of lime on CBR behavior of
fly ash - mine overburden mixes. Tests were performed with different
percentages of lime (2%, 3%, 6%, and 9%). The results show that the
increase in bearing ratio of fly ash-overburden mixes was achieved
by lime treatment. Scanning electron microscopy (SEM) analyses
were conducted on 28 days cured specimens. The SEM study showed
that the bearing ratio development is related to the microstructural
development.
Abstract: A water surface slope limiting scheme is tested and
compared with the water depth slope limiter for the solution of one
dimensional shallow water equations with bottom slope source term.
Numerical schemes based on the total variation diminishing Runge-
Kutta discontinuous Galerkin finite element method with slope
limiter schemes based on water surface slope and water depth are
used to solve one-dimensional shallow water equations. For each
slope limiter, three different Riemann solvers based on HLL, LF, and
Roe flux functions are used. The proposed water surface based slope
limiter scheme is easy to implement and shows better conservation
property compared to the slope limiter based on water depth. Of the
three flux functions, the Roe approximation provides the best results
while the LF function proves to be least suitable when used with
either slope limiter scheme.
Abstract: Abstract— The paper presents a preliminary study on modeling and estimation of basic wind speed ( extreme wind gusts ) for the consideration of vulnerability and design of building in Ayeyarwady Region. The establishment of appropriate design wind speeds is a critical step towards the calculation of design wind loads for structures. In this paper the extreme value analysis of this prediction work is based on the anemometer data (1970-2009) maintained by the department of meteorology and hydrology of Pathein. Statistical and probabilistic approaches are used to derive formulas for estimating 3-second gusts from recorded data (10-minute sustained mean wind speeds).
Abstract: The mountain road slope failures triggered by
earthquake activities and torrential rain namely to create the disaster.
Province Road No. 24 is a main route to the Wutai Township. The area
of the study is located at the mileages between 46K and 47K along the
road. However, the road has been suffered frequent damages as a result
of landslide and slope failures during typhoon seasons. An
understanding of the sliding behaviors in the area appears to be
necessary. Slope failures triggered by earthquake activities and heavy
rainfalls occur frequently. The study is to understand the mechanism
of slope failures and to look for the way to deal with the situation. In
order to achieve these objectives, this paper is based on theoretical and
structural geology data interpretation program to assess the potential
slope sliding behavior. The study showed an intimate relationship
between the landslide behavior of the slopes and the stratum materials,
based on structural geology analysis method to analysis slope stability
and finds the slope safety coefficient to predict the sites of destroyed
layer. According to the case study and parameter analyses results, the
slope mainly slips direction compared to the site located in the
southeast area. Find rainfall to result in the rise of groundwater level is
main reason of the landslide mechanism. Future need to set up
effective horizontal drain at corrective location, that can effective
restrain mountain road slope failures and increase stability of slope.
Abstract: Estimation of stormwater pollutants is a pre-requisite
for the protection and improvement of the aquatic environment and
for appropriate management options. The usual practice for the
stormwater quality prediction is performed through water quality
modeling. However, the accuracy of the prediction by the models
depends on the proper estimation of model parameters. This paper
presents the estimation of model parameters for a catchment water
quality model developed for the continuous simulation of stormwater
pollutants from a catchment to the catchment outlet. The model is
capable of simulating the accumulation and transportation of the
stormwater pollutants; suspended solids (SS), total nitrogen (TN) and
total phosphorus (TP) from a particular catchment. Rainfall and water
quality data were collected for the Hotham Creek Catchment (HTCC),
Gold Coast, Australia. Runoff calculations from the developed model
were compared with the calculated discharges from the widely used
hydrological models, WBNM and DRAINS. Based on the measured
water quality data, model water quality parameters were calibrated
for the above-mentioned catchment. The calibrated parameters are
expected to be helpful for the best management practices (BMPs)
of the region. Sensitivity analyses of the estimated parameters were
performed to assess the impacts of the model parameters on overall
model estimations of runoff water quality.
Abstract: This study presents the application of artificial
neural network for modeling the phenolic compound
migration through vertical soil column. A three layered feed
forward neural network with back propagation training
algorithm was developed using forty eight experimental data
sets obtained from laboratory fixed bed vertical column tests.
The input parameters used in the model were the influent
concentration of phenol(mg/L) on the top end of the soil
column, depth of the soil column (cm), elapsed time after
phenol injection (hr), percentage of clay (%), percentage of
silt (%) in soils. The output of the ANN was the effluent
phenol concentration (mg/L) from the bottom end of the soil
columns. The ANN predicted results were compared with the
experimental results of the laboratory tests and the accuracy of
the ANN model was evaluated.
Abstract: This paper presents the results of preliminary
assessment of water quality along the coastal areas in the vicinity of
Left Bank Outfall Drainage (LBOD) and Tidal Link Drain (TLD) in
Sindh province after the cyclone 2A occurred in 1999. The water
samples were collected from various RDs of Tidal Link Drain and
lakes during September 2001 to April 2002 and were analysed for
salinity, nitrite, phosphate, ammonia, silicate and suspended material
in water. The results of the study showed considerable variations in
water quality depending upon the location along the coast in the
vicinity of LBOD and RDs. The salinity ranged between 4.39–65.25
ppt in Tidal Link Drain samples whereas 2.4–38.05 ppt in samples
collected from lakes. The values of suspended material at various
RDs of Tidal Link Drain ranged between 56.6–2134 ppm and at the
lakes between 68–297 ppm. The data of continuous monitoring at
RD–93 showed the range of PO4 (8.6–25.2 μg/l), SiO3 (554.96–1462
μg/l), NO2 (0.557.2–25.2 μg/l) and NH3 (9.38–23.62 μg/l). The
concentration of nutrients in water samples collected from different
RDs was found in the range of PO4 (10.85 to 11.47 μg/l), SiO3 (1624
to 2635.08 μg/l), NO2 (20.38 to 44.8 μg/l) and NH3 (24.08 to 26.6
μg/l). Sindh coastal areas which situated at the north-western
boundary the Arabian Sea are highly vulnerable to flood damages
due to flash floods during SW monsoon or impact of sea level rise
and storm surges coupled with cyclones passing through Arabian Sea
along Pakistan coast. It is hoped that the obtained data in this study
would act as a database for future investigations and monitoring of
LBOD and Tidal Link Drain coastal waters.