Abstract: Under active stress conditions, a rigid cantilever
retaining wall tends to rotate about a pivot point located within the
embedded depth of the wall. For purely granular and cohesive soils, a
methodology was previously reported called minimization of moment
ratio to determine the location of the pivot point of rotation. The
usage of this new methodology is to estimate the rotational stability
safety factor. Moreover, the degree of improvement required in a
backfill to get a desired safety factor can be estimated by the concept
of the shear strength demand. In this article, the accuracy of this
method for another type of cantilever walls called Contiguous Bored
Pile (CBP) retaining wall is evaluated by using physical modeling
technique. Based on observations, the results of moment ratio
minimization method are in good agreement with the results of the
carried out physical modeling.
Abstract: A pilot field study was conducted at the Jagjeetpur
Municipal Sewage treatment plant situated in the Haridwar town in
Uttarakhand state, India. The objectives of the present study were to
study the effect of treated wastewater on the production of various
paddy varieties (Sharbati, PR-114, PB-1, Menaka, PB1121 and PB
1509) and the emission of GHG gases (CO2, CH4 and N2O) as
compared to the same varieties grown in the control plots irrigated
with fresh water. Of late, the concept of water footprint assessment
has emerged, which explains enumeration of various types of water
footprints of an agricultural entity from its production to processing
stages. Paddy, the most water demanding staple crop of Uttarakhand
state, displayed a high green water footprint value of 2474.12 m3/
Ton. Most of the wastewater irrigated varieties displayed up to 6%
increase in production, except Menaka and PB-1121, which showed a
reduction in production (6% and 3% respectively), due to pest and
insect infestation. The treated wastewater was observed to be rich in
Nitrogen (55.94 mg/ml Nitrate), Phosphorus (54.24 mg/ml) and
Potassium (9.78 mg/ml), thus rejuvenating the soil quality and not
requiring any external nutritional supplements. A Percentage increase
of GHG gases of irrigation with treated municipal wastewater as
compared to control plots was observed as 0.4% - 8.6% (CH4), 1.1%
- 9.2% (CO2), and 0.07% - 5.8% (N2O). The variety, Sharbati,
displayed maximum production (5.5 ton/ha) and emerged as the most
resistant variety against pests and insects. The emission values of
CH4, CO2 and N2O were 729.31 mg/m2/d, 322.10 mg/m2/d and
400.21 mg/m2/d in water stagnant condition.
This study highlighted a successful possibility of reuse of
wastewater for non-potable purposes offering the potential for
exploiting this resource that can replace or reduce the existing use of
fresh water sources in agriculture sector.
Abstract: The heavy metal pollution of the soils around the mining area near Shamlugh town and related risks to human health were assessed. The investigations showed that the soils were polluted with heavy metals that can be ranked by anthropogenic pollution degree as follows: Cu>Pb>As>Co>Ni>Zn. The main sources of the anthropogenic metal pollution of the soils were the copper mining area near Shamlugh town, the Chochkan tailings storage facility and the trucks transferring ore from the mining area. Copper pollution degree in some observation sites was unallowable for agricultural production. The total non-carcinogenic chronic hazard index (THI) values in some places, including observation sites in Shamlugh town, were above the safe level (THI
Abstract: For this study, a town based soil database created in
Gümüsçay District of Biga Town, Çanakkale, Turkey. Crop and
livestock production are major activities in the district. Nutrient
management is mainly based on commercial fertilizer application
ignoring the livestock manure. Within the boundaries of district, 122
soil sampling points determined over the satellite image. Soil samples
collected from the determined points with the help of handheld
Global Positioning System. Labeled samples were sent to a
commercial laboratory to determine 11 soil parameters including
salinity, pH, lime, organic matter, nitrogen, phosphorus, potassium,
iron, manganese, copper and zinc. Based on the test results soil maps
for mentioned parameters were developed using remote sensing, GIS,
and geostatistical analysis. In this study we developed a GIS database
that will be used for soil nutrient management. Methods were
explained and soil maps and their interpretations were summarized in
the study.
Abstract: The addition of lime as Ca(OH)2 to sewage sludge to
destroy pathogens (Escherichia coli), was evaluated also in relation
to heavy metal bioavailability.
The obtained results show that the use of calcium hydroxide at the
dose of 3% effectively destroyed pathogens ensuring the stability at
high pH values over long period and the duration of the sewage
sludge stabilization. In general, lime addition decreased the total
extractability of heavy metals indicating a reduced bioavailability of
these elements. This is particularly important for a safe utilization in
agricultural soils to reduce the possible transfer of heavy metals to
the food chain.
Abstract: Froth flotation remains to date as one of the most used
metallurgical processes for concentrating metal-bearing minerals in
ores. Oxide ores are relatively less amenable to froth flotation and
require a judicious choice of reagents for the recovery of metals to be
optimised. Laboratory batch flotation tests were conducted to
determine the effect of two types of gasoil-rinkalore mixtures on the
flotation response of a copper cobalt oxide ore sample. The head
assay conducted on the initial ore sample showed that it contained
about 2.90% of Cu, 0.12% of Co.
Upon the flotation test work, the results obtained indicated that the
concentrate obtained with use of the mixture gazoil-rinkalore RX
yielded 8.24% Cu and 0.22% Co concentrate grades with recoveries
of 76.0% Cu and 78.0% Co respectively. But, the concentrate
obtained by use of the mixture gazoil-rinkalore RX3 yielded
relatively bad results with 5.92% Cu and 0.18% Cu concentrate
grades with recoveries of 70.3% Cu and 65.3% Co respectively.
Abstract: Brass terminal, one of the several crude oil and
petroleum products storage/handling facilities in the Niger Delta was
built in the 1980s. Activities at this site, over the years, released
crude oil into this 3 m-deep, 1500 m-long canal lying adjacent to the
terminal with oil floating on it and its sediment heavily polluted. To
ensure effective clean-up, three major activities were planned: site
characterization, bioremediation pilot plant construction and testing
and full-scale bioremediation of contaminated sediment / bank soil by
land farming. The canal was delineated into 12 lots and each
characterized, with reference to the floating oily phase, contaminated
sediment and canal bank soil. As a result of site characterization, a
pilot plant for on-site bioremediation was designed and a treatment
basin constructed for carrying out pilot bioremediation test.
Following a designed sampling protocol, samples from this pilot
plant were collected for analysis at two laboratories as a quality
assurance / quality control check. Results showed that Brass Canal
upstream is contaminated with dark, thick and viscous oily film with
characteristic hydrocarbon smell while downstream, thin oily film
interspersed with water was observed. Sediments were observed to be
dark with mixture of brownish sandy soil with TPH ranging from
17,800 mg/kg in Lot 1 to 88,500 mg/kg in Lot 12 samples. Brass
Canal bank soil was observed to be sandy from ground surface to 3m,
below ground surface (bgs) it was silty-sandy and brownish while
subsurface soil (4-10m bgs) was sandy-clayey and whitish/grayish
with typical hydrocarbon smell. Preliminary results obtained so far
have been very promising but were proprietary. This project is
considered, to the best of technical literature knowledge, the first
large-scale on-site bioremediation project in the Niger Delta region,
Nigeria.
Abstract: A field study was conducted to evaluate the efficacy of
safflower plant for phytoremediation of contaminated soils. The
experiment was performed on an agricultural fields contaminated by
the Non-Ferrous-Metal Works near Plovdiv, Bulgaria. Field
experiments with randomized complete block design with five
treatments (control, compost amendments added at 20 and 40 t/daa,
and vermicompost amendments added at 20 and 40 t/daa) were
carried out. The quality of safflower seeds and oil (heavy metals and
fatty acid composition) were determined. Tested organic amendments
significantly influenced the chemical composition of safflower seeds
and oil. The compost and vermicompost treatments significantly
reduced heavy metals concentration in safflower seeds and oils, but
the effect differed among them. Addition of vermicompost and
compost leads to an increase in the content of palmitic acid and
linoleic acid, and a decrease in the stearic and oleic acids compared
with the control. A significant increase in the quantity of saturated
acids was observed in the variants with 20 t/daa of compost and 20
t/daa of vermicompost (9.1 and 8.9% relative to the control).
Safflower is a plant which is tolerant to heavy metals and can be
successfully used in the phytoremediation of heavy metal
contaminated soils. The processing of seeds to oil and using the
obtained oil for nutritional purposes will greatly reduce the cost of
phytoremediation.
Abstract: The arsenic and iron environments in different growth
stages have been studied with EXAFS and XANES using
Brookhaven Synchrotron Light Source. Collard Greens plants were
grown and tissue samples were harvested. The project studied the
EXAFS and XANES of tissue samples using As and Fe K-edges. The
Fe absorption and the Fourier transform bond length information
were used as a control comparison. The Fourier transform of the
XAFS data revealed the coexistence of As (III) and As (V) in the As
bonding environment inside the studied plant tissue samples,
although the soil only had As (III). The data suggests that Collard
Greens has a novel pathway to handle arsenic absorption in soil.
Abstract: This study investigated the behavior of improved soft soils through the vibro replacement technique by considering their settlements and consolidation rates and the applicability of this technique in various types of soils and settlement and bearing capacity calculations.
Abstract: A field study was conducted to evaluate the efficacy
of lavender for phytoremediation of contaminated soils. The
experiment was performed on an agricultural fields contaminated by
the Non-Ferrous-Metal Works near Plovdiv, Bulgaria. The
concentrations of Pb, Zn and Cd in lavender (roots, stems, leaves and
inflorescences) and in the essential oils of lavender were determined.
Lavender is a plant which is tolerant to heavy metals and can be
grown on contaminated soils, and which can be referred to the
hyperaccumulators of lead and the accumulators of cadmium and
zinc, and can be successfully used in the phytoremediation of heavy
metal contaminated soils. Favorable is also the fact that heavy metals
do not influence the development of the lavender, as well as on the
quality and quantity of the essential oil. The possibility of further
industrial processing will make lavender economically interesting
crops for farmers of phytoextraction technology.
Abstract: The model tests were conducted in the laboratory
without and with Plastic recycled polymer in fly ash steep slopes
overlaying soft foundation soils like fly ash and powai soil in order to
check the stability of steep slope. In this experiment, fly ash is used
as a filling material and Plastic Recycled Polymers of diameter =
3mm and length = 4mm were made from waste plastic product (lower
grade plastic product). The properties of fly ash and Plastic recycled
polymers are determined. From the experiments, load and settlement
have measured. From these data, load –settlement curves have
reported. It has been observed from test results that load carrying
capacity of mixture fly ash with Plastic Recycled Polymers slope is
more than that of fly ash slope. The deformation of Plastic Recycled
Polymers slope is slightly more than that of fly ash slope. A Finite
Element Method (F.E.M.) was also evaluated using PLAXIS 3D
version. The failure pattern, deformations and factor of safety are
reported based on analytical programme. The results from
experimental data and analytical programme are compared and
reported.
Abstract: This paper is part of a study to develop robots for
farming. As such power requirement to operate equipment attach to
such robots become an important factor. Soil-tool interaction plays
major role in power consumption, thus predicting accurately the
forces which act on the blade during the farming is very important for
optimal designing of farm equipment. In this paper, a finite element
investigation for tillage tools and soil interaction is described by
using an inelastic constitutive material law for agriculture
application. A 3-dimensional (3D) nonlinear finite element analysis
(FEA) is developed to examine behavior of a blade with different
rake angles moving in a block of soil, and to estimate the blade force.
The soil model considered is an elastic-plastic with non-associated
Drucker-Prager material model. Special use of contact elements are
employed to consider connection between soil-blade and soil-soil
surfaces. The FEA results are compared with experimental ones,
which show good agreement in accurately predicting draft forces
developed on the blade when it moves through the soil. Also a very
good correlation was obtained between FEA results and analytical
results from classical soil mechanics theories for straight blades.
These comparisons verified the FEA model developed. For analyzing
complicated soil-tool interactions and for optimum design of blades,
this method will be useful.
Abstract: The use of energy dissipation systems for seismic applications has increased worldwide, thus it is necessary to develop practical and modern criteria for their optimal design. Here, a direct displacement-based seismic design approach for frame buildings with hysteretic energy dissipation systems (HEDS) is applied. The building is constituted by two individual structural systems consisting of: 1) a main elastic structural frame designed for service loads; and 2) a secondary system, corresponding to the HEDS, that controls the effects of lateral loads. The procedure implies to control two design parameters: a) the stiffness ratio (α=Kframe/Ktotal system), and b) the strength ratio (γ=Vdamper/Vtotal system). The proposed damage-controlled approach contributes to the design of a more sustainable and resilient building because the structural damage is concentrated on the HEDS. The reduction of the design displacement spectrum is done by means of a damping factor (recently published) for elastic structural systems with HEDS, located in Mexico City. Two limit states are verified: serviceability and near collapse. Instead of the traditional trial-error approach, a procedure that allows the designer to establish the preliminary sizes of the structural elements of both systems is proposed. The design methodology is applied to an 8-story steel building with buckling restrained braces, located in soft soil of Mexico City. With the aim of choosing the optimal design parameters, a parametric study is developed considering different values of હ and . The simplified methodology is for preliminary sizing, design, and evaluation of the effectiveness of HEDS, and it constitutes a modern and practical tool that enables the structural designer to select the best design parameters.
Abstract: A reliability-based methodology which uses structural demand hazard curves to consider the increment of the ductility demands of structures with tilting is proposed. The approach considers the effect of two orthogonal components of the ground motions as well as the influence of soil-structure interaction. The approach involves the calculation of ductility demand hazard curves for symmetric systems and, alternatively, for systems with different degrees of asymmetry. To get this objective, demand hazard curves corresponding to different global ductility demands of the systems are calculated. Next, Uniform Exceedance Rate Spectra (UERS) are developed for a specific mean annual rate of exceedance value. Ratios between UERS corresponding to asymmetric and to symmetric systems located in soft soil of the valley of Mexico are obtained. Results indicate that the ductility demands corresponding to tilted structures may be several times higher than those corresponding to symmetric structures, depending on several factors such as tilting angle and vibration period of structure and soil.
Abstract: A cyclostationary Gaussian linearization method is
formulated for investigating the time average response of nonlinear
system under sinusoidal signal and white noise excitation. The
quantitative measure of cyclostationary mean, variance, spectrum of
mean amplitude, and mean power spectral density of noise are
analyzed. The qualitative response behavior of stochastic jump and
bifurcation are investigated. The validity of the present approach in
predicting the quantitative and qualitative statistical responses is
supported by utilizing Monte Carlo simulations. The present analysis
without imposing restrictive analytical conditions can be directly
derived by solving non-linear algebraic equations. The analytical
solution gives reliable quantitative and qualitative prediction of mean
and noise response for the Duffing system subjected to both sinusoidal
signal and white noise excitation.
Abstract: Poly bag and mulch films for agricultural field caused
pose environmental problem due to the non-degradable plastics
wastes upon disposal. Thus, a degradable poly bag was designed with
hybrid sago starch (SS) and polyvinyl alcohol (PVA). Two Different
blended compositions of SS and PVA hybrid have been compounded.
Then, the hybrids blended are mixed with linear line density
polyethylene (LLDPE) resin to fabricate poly bag film through
conventional film blowing process. Samples of LLDPE, SS and PVA
hybrid film were exposed to UV light and soil burial. The weight
losses were determined during degradation process. Hybrid film by
degradation of starch was found to hydrolyze and hydroxyl groups
decrease on esterification upon exposure to soil burial and uv
radiation. It was found out that, the hybrid film for 60% of SS
composition showed greatest degradation in soil and UV radiation.
Abstract: Phelipanche ramosa is the most damaging obligate
flowering parasitic weed on wide species of cultivated plants. The
semi-arid regions of the world are considered the main centers of this
parasitic plant that causes heavy infestation. This is due to its
production of high numbers of seeds (up to 200,000) that remain
viable for extended periods (up to 20 years). In this study, 13
treatments for the control of Phelipanche were carried out, which
included agronomic, chemical, and biological treatments and the use
of resistant plant methods. In 2014, a trial was performed at the
Department of Agriculture, Food and Environment, University of
Foggia (southern Italy), on processing tomato (cv ‘Docet’) grown in
pots filled with soil taken from a field that was heavily infested by P.
ramosa). The tomato seedlings were transplanted on May 8, 2014,
into a sandy-clay soil (USDA). A randomized block design with 3
replicates (pots) was adopted. During the growing cycle of the
tomato, at 70, 75, 81 and 88 days after transplantation, the number of
P. ramosa shoots emerged in each pot was determined. The tomato
fruit were harvested on August 8, 2014, and the quantitative and
qualitative parameters were determined. All of the data were
subjected to analysis of variance (ANOVA) using the JMP software
(SAS Institute Inc. Cary, NC, USA), and for comparisons of means
(Tukey's tests). The data show that each treatment studied did not
provide complete control against P. ramosa. However, the virulence
of the attacks was mitigated by some of the treatments tried: radicon
biostimulant, compost activated with Fusarium, mineral fertilizer
nitrogen, sulfur, enzone, and the resistant tomato genotype. It is
assumed that these effects can be improved by combining some of
these treatments with each other, especially for a gradual and
continuing reduction of the “seed bank” of the parasite in the soil.
Abstract: The aim of the present study was to examine whether
increasing molybdenum (Mo) concentration affects the growth and
Mo concentration of maize (Zea mays L. cv Norma SC) and
sunflower (Helianthus annuus L. cv Arena PR) seedlings within
laboratory conditions.
In this experiment, calcareous chernozem soil was used and Mo
was supplemented into the soil as ammonium molybdate
[(NH4)6Mo7O24.4H2O] in four different concentrations as follow: 0
(control), 30, 90 and 270 mg·kg-1.
In this study, we found that molybdenum in small amount (30
mg·kg-1) affects positively on growth of maize and sunflower
seedlings, however, higher concentration of Mo reduces the dry
weights of shoots and roots. In the case of maize the highest Mo
treatment (270 mg·kg-1) and in sunflower 90 mg·kg-1 treatment
caused significant reduction in plant growth.
In addition, we observed that molybdenum contents in the roots
and shoots were very low in case of control soil but were
significantly elevated with increasing concentration of Mo treatment.
Only in case of sunflower the highest 270 mg·kg-1 Mo treatment
caused decrease in Mo concentration.
Abstract: An innovative concept called “Flexy-Energy” is developing at 2iE. This concept aims to produce electricity at lower cost by smartly mix different available energy sources in accordance to the load profile of the region. With a higher solar irradiation and due to the fact that Diesel generator are massively used in sub-Saharan rural areas, PV/Diesel hybrid systems could be a good application of this concept and a good solution to electrify this region, provided they are reliable, cost effective and economically attractive to investors. Presentation of the developed approach is the aims of this paper. The PV/Diesel hybrid system designed consists to produce electricity and/or heat from a coupling between Diesel Diesel generators and PV panels without batteries storage, while ensuring the substitution of gasoil by bio-fuels available in the area where the system will be installed. The optimal design of this system is based on his technical performances; the Life Cycle Cost (LCC) and Levelized Cost of Energy are developed and use as economic criteria. The Net Present Value (NPV), the internal rate of return (IRR) and the discounted payback (DPB) are also evaluated according to dual electricity pricing (in sunny and unsunny hours). The PV/Diesel hybrid system obtained is compared to the standalone Diesel Diesel generators. The approach carried out in this paper has been applied to Siby village in Mali (Latitude 12 ° 23'N 8 ° 20'W) with 295 kWh as daily demand.This approach provides optimal physical characteristics (size of the components, number of component) and dynamical characteristics in real time (number of Diesel generator on, their load rate, fuel specific consumptions, and PV penetration rate) of the system. The system obtained is slightly cost effective; but could be improved with optimized tariffing strategies.