Table of content

Journal of Engineering and Sustainable Development

مجلة الهندسة والتنمية المستدامة

ISSN: 25200917
Publisher: Al-Mustansyriah University
Faculty: Engineering
Language: Arabic and English

This journal is Open Access

About

Journal of Engineering and Sustainable Development
College of Engineering /Mustansiriyah University
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• About the journal
The Journal of Engineering and Sustainable Development is a peer reviewed open access scientific Iraqi journal issued by the College of Engineering/ Mustansiriyah University, under the regulations and standards of the Ministry of Higher Education and Scientific Research in Iraq. In the meantime, the journal commits itself to the regulations of the Committee On Publication Ethics (COPE).


The Journal of Engineering and Sustainable Development is an open access journal that all contents are free of charge. Users are allowed to read, download, or share the full texts of the articles in this journal without prior permission of the publisher or the author(s). A DOI is guaranteed by no means to change, so it can be used as a permanent link to any electronic article. Our journal DOI prefix account is 10.31272.

The journal welcomes submissions in the following topics:

Structural Engineering

Geotechnical Engineering

Engineering Management

Materials Engineering

Transportation Engineering

Dam and Water Resources Engineering

Architectural Engineering and Urban Design

Energy and Power System

Electronics, Control, Signals and Systems

Computer and Software Engineering

Communication Engineering

Renewable Energy Systems

Environmental Engineering

General Engineering

The vision for the future is to make the journal abstracted and indexed by the prominent databases and internationally cited, read and downloaded by the scholars. The mission is to contribute to the advances in the engineering fields and sustainable development. The journal aims at revolutionizing the practice in industry by promoting cutting-edge and effective research.

The Journal of Engineering and Sustainable Development is published bimonthly, and the issues appearing on the beginning of each other month.

The corresponding author must pay fees of 100000 Iraqi dinars for the professor academic title, 75000 Iraqi dinars for assistant professor or less title, and 30000 Iraqi dinars for graduate (or undergraduate) students where the student is the first author. For international researchers, the submission fees are 125 USD.

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Contact info

Phone Number:07717944560
E-mail:editor@jeasd.org
ali.alghalib@uomustansiriyah.edu.iq

Table of content: 2018 volume:22 issue:4

Article
EXPERIMENTAL STUDY OF REINFORCED CONCRETE DAPPED ENDS BEAMS STRENGTHEN WITH TRANSVERSE SUBSEQUENT INSTALLED BARS

Authors: Hadi Nasir Ghadhban
Pages: 1-14
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Abstract

Abstract: This study involves in taking seven reinforced concrete dapped end beams strengthened with transverse Subsequent installed bars under concentered loads. These specimens of dimension (length=1220 x height=240 x width=130mm) with two types of sections (i.e. without and with transverse opening) and studied to evaluate the response of test beams to compare the strength capacity of beams strengthened with transvers subsequent installed bars relative to beams with or without opening region in sections. All specimens are simply supports. The five of R.C. dapped ends beams are strengthened with transverses Subsequent installed bars with or without opening and designed to test up to failure. Three parameters were investigated: compressive strength, amount of transvers Subsequent installed bars, and effect of section (with and without opening). It is found that’s increased in compressive strength by about 20% give increase in load carrying capacity by about 9%. Also, the reinforced concrete dapped ends beams contains transverse opening section compared to beams without opening results show decrease in strength capacity and gives more deflection by about in range (10-20%) and (18-26%) respectively. The transverse Subsequent installed bars are provided by steel bolts diameter of 10.5mm gives more enhancement in strength capacity and decrease deflection more than the others without transvers bars by about (8-27%) & (20-30%). Strengthened of beams by transvers bars can show to again in ultimate strength capacity by about (30%).


Article
توظيف خصائص الشكل الطبيعي في التطبيقات المعمارية المعاصرة

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ان توجه العمارة نحو الطبيعة عبر تاريخها امر ليس بالجديد, فقد اعتبر المعماريون الطبيعة كأحد المصادر المهمة في إلهامهم في التصميم. وشهدت العشرون سنة الماضية فهما عميقا لخصائص الشكل الطبيعي تبعا لتنظيمها وفقا للهندسة الكسرية. اذ فضل العديد من المعماريين المعاصرين توظيف خصائص الشكل الطبيعي في التصميم, وتمركزت طروحاتهم حول هذه الخصائص خلال محاكاة الخصائص الشكلية والوظيفية والهيكلية المرتبطة بالشكل الطبيعي. وتحددت مشكلة البحث في: "النقص المعرفي في تحديد خصائص الشكل الطبيعي في العمارة المعاصرة". وبذلك هدف البحث الى: "تحديد خصائص الشكل الطبيعي في العمارة المعاصرة". تم شرح الخصائص الشكلية والوظيفية والهيكلية للشكل الطبيعي لتحديد مؤشرات القياس, والتي تم استخدامها لمقارنة الحالات الدراسية المختارة. واستنتج البحث بانه قد تم استخدام الخصائص الشكلية دون الوظيفية والهيكلية باستثناء التحوير الكمي1 الذي تم استخدامه في كل المشاريع المنتخبة.


Article
DYNAMIC SHORTEST PATH ANALYSIS OF ROUTING TECHNIQUE VIA GENETIC ALGORITHM

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Abstract

The performance and reliability of the internet depend in large part on properties of routing techniques. IP routing protocols nowadays compute paths based on the network configuration parameters and topology, missing view to the current traffic load on the routers and links. This paper discusses routing optimization using Genetic Algorithm (GA) then studies and analyzes the problems in order to increase routing performance in median networks. A genetic algorithm will be proposed in a detail to advise the performance of Open Shortest Path First (OSPF) routing Protocol. The simulated results show that the probability of convergence to shortest path has been superior via momentary using GA in OSPF protocol.


Article
تقليل ملوثات عادم محرك اشعال بالضغط باستخدام مزيج الديزل – الايثانول

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: اصبح الطلب على الوقود البديل من الأمور المهمة جدا بسبب تقلب اسعار النفط في العالم وكذلك للتقليل من كمية الغازات الملوثة للبيئة. تهدف هذه الدراسة الى معرفة تأثير نسب خليط الديزل – الايثانول على اداء محرك الديزل ونسب التلوث الناتجة منه. اجريت تجارب عملية لدراسة تاثير وقود الديزل / الايثانول بنسب متغيرة هي (5%, 8%, 10%). تم اجراء هذه التجارب عند قيم متغيرة لسرعة المحرك تراوحت بين (1100- 2600 rpm)، وقيــم متغيـرة للحمل المسلط على هذا المحرك (2 – 10 N.m)، تم قياس مواصفات اداء المحرك المختلفة وغازات العادم الأكثر ضررا على البيئة وهي اول اوكسيد الكاربون (CO) ، والهيروكاربونات الغير محترقة (HC)، واكاسيد النتروجين (NOx) . من خلال النتائج المستحصلة يلاحظ ان القدرتين البيانية والمكبحية واللتان تزدادان طرديا مع سرعة المحرك ينخفضان عند زيادة نسبة الايثانول في مزيج وقود الديزل والايثانول، وكذلك الحال مع الكفاءة الحرارية البيانية ودرجة حرارة العادم اللذان ينخفضان مع زيادة هذه النسبة ولكن هذا الانخفاض يقل عند الاحمال العالية، بينما يلاحظ ان الأستهلاك النوعي الفرملي للوقود يزداد عند زيادة نسبة الأيثانول في الخليط . كما وجد ان خليط الديزل – الايثانول يعطي قيم تاخر اشعال طويلة بسبب مقاومته العالية للأشتعال الذاتي مقارنة مع وقود الديزل الصافي، ولهذا فان الضغط الأقصى في الأسطوانة يقل عند استخدام خليط الديزل – الايثانول مقارنة بوقود الديزل الصافي لأن درجة حرارة احتراق الأيثانول تكون واطئة، كما ان اضافة الايثانول الى الديزل ادى الى انخفاض في قيم اكاسيد النتروجين (NOx) كذلك الحال مع قيم انبعاث اول اوكسيد الكاربون (CO)والهيدروكاربونات الغير محترقة (HC) الناتجة من احتراق هذا الخليط في محرك الديزل.


Article
STRUCTURAL BEHAVIOR OF THIN RPC WALL PANELS WITH VARYING STEEL REINFORCEMENT AND ASPECT RATIO SUBJECTED TO AXIAL ECCENTRIC UNIFORMLY DISTRIBUTED LOADING

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This paper presents experimental study of structural behavior of thin Reactive Powder Concrete (RPC) wall panels subjected to axial eccentric uniformly distributed loading with varying steel reinforcement ratio (ρ) and aspect ratio (AR= H/L). The experimental program included testing of six two-way thin RPC wall panels, fixed at all sides and applying the load axially with eccentricity equal to (t/6). The results indicates that the ultimate strength of the RPC wall panel decreases with increase in AR from (1.25 to 2.00) for panels with H/t = 18.75. The decreasing in ultimate load for RPC wall panels is about 16% and 38.7%, for an increase in AR from 1.25 to 2.0 for panels with ρ = 0.012566, and about 6.38% and 36.2%, for an increase in AR from 1.25 to 2.0 for panels with ρ = 0.007854.The ultimate strength of RPC wall panel increases with an increase of percentage of steel reinforcement ratio (ρ). For an increase in reinforcement ratio from ρ = 0.007854 to ρ = 0.012566 the increase is about (6.4, 4.76 and 2.22) % for walls with AR (1.25, 1.50 and 2.00) respectively. The lateral deflection decrease with the increase of percentage of steel reinforcement ratio from (0.007854 to 0.012566) under two-way in plane loading, When AR= 1.25 the reduction about (1.22 times) and When AR= 2.00 the reduction about (1.11 times). The lateral deflection of RPC wall panels decrease with the increase in aspect ratio.


Article
THE EFFECT OF USING LAYERED GEOGRID REINFORCEMENT ON THE COLLAPSIBILITY OF GYPSEOUS SOILS

Authors: *Raghad Mohammed Kudadad
Pages: 39-56
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Abstract

The geotechnical engineering considers the gypseous soils as collapsible soils. The existence of these soils causes problems for the structures, because of the dissolution and filtration of the gypsum from soil texture by the flow of water through the soil mass, this problem was the focus of attention of many researchers over the years to improve the properties of these soils. This research aims to study the effect of using geogrid reinforcement to reduce the collapse of gypseous soils upon soaking. A series of laboratory models tests in addition to routine laboratory tests carried out on three soils with different gypsum contents. The soils were brought from AL-Najaf district, the first soil S1 was taken from 0.5 meter below the ground surface with high gypsum content (26%). The second soil S2 was taken from 4 meter below the ground surface, with Slight gypsum content (6.9%), the third soil S3 was artificially prepared, by mixing the first soil S1 with the second soil S2 to get the required moderate gypsum content. A new technique manufactured locally for this work and a series of tests including dry and soak tests carried out using steel container (280×280×250) mm. The soils were placed in steel container at their field densities. The single layer geogrid reinforcement test was conducted by placing the geogrid layer at three different depths for all soils [(Depth of the reinforcement layer, D = 0.25 width of foundation, B), (D = 0.5B) and (D = 0.75B)]. The study includes also the effect of number of reinforcing layers (N) on the collapse behavior of gypseous soils. The models were reinforced with N=1, N=2 and N=3 (the vertical distance between geogrid layers, Z=0.25B). The study includes the observation of collapsibility of soaked gypseous soils at stress level of 100 kPa. A strip footing of (270×40×30) mm dimensions was taken as a testing model. This footing was placed at the center of the top surface of the bed soil. For all testing models, the footing was loaded gradually up to 100 kPa, after 24 hours, the corresponding settlement was recorded. Then, the soil is soaked for 24 hours and the generated settlement recorded under the same stress level 100 kPa. The results showed that the most effective depth for single layer reinforcement is at (D=0.25B) for the three soils, which gives a collapse reduction factor (CRF) of about (28.5%, 29.41%, 30.43%) for soils (S1, S2, S3) respectively. The effective number of reinforcement layers was (N=3: D=0.25B: Z=0.25B), which gives (CRF) of about (54.08%, 82.35%, 69.56%) for (S1, S2, S3) respectively compared with unreinforced model.


Article
INVESTIGATING OF THE BEHAVIOR OF PILE GROUPS UNDER THE EFFECT OF SUCTION POTENTIAL OF UNSATURATED EXPANSIVE SOIL

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: This research presents an experimental study and numerical modelling to investigate the load-carrying capacity of a group of piles embedded in unsaturated expansive soil. The experimental work consists of a model of group of piles tested under unsaturated condition. The matric suction of the soil is measured by the Tensiometers to estimate the soil water characteristic curve (SWCC) by applying a fitting method. The experimental model is performed to validate the numerical modeling of the investigated problem using finite element method. A three-dimensional numerical modelling of a large-scale model is adopted to perform a parametric study on a group of piles in unsaturated expansive soil to investigate the effect of different parameters, such as depth of phreatic surface and initial degree of saturation on the load- carrying capacity. The results showed that a good agreement for the validation process. In addition, the load-carrying capacity increases when the depth of phreatic surface from the ground surface increases, also the decreasing in the initial degree of saturation of the soil lead to an increase in load-carrying capacity


Article
EFFECT OF CARBON NANO TUBES ON EROSION WEAR OF CARBON FIBER, GLASS FIBER & KEVLAR FIBER REINFORCED UNSATURATED POLYESTER COMPOSITES

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Abstract

In the present study, nano composites were prepared by Hand lay-up molding. The nano composites component of the unsaturated polyester resin (UP) as a matrix, 3% volume fractions of Carbon Fiber (C.F), Glass Fibers (G.F), Kevlar Fiber (K.F) as reinforcement and (0.5%,1%, 1.5% and 2%) volume fractions of Carbon Nanotubes (CNTs) as filler. The erosion wear behavior of this nano composite at four different impingement angles 30°, 45°, 60° and 90° and four angular silica sand abrasive particle sizes 400, 500 , 600 and 800 μm and density were studied. The results showed that the specimens (UP + 3% (GF, CF, KF) +2% CNTs) have the maximum density when compared with the other volume fractions. The non – reinforced unsaturated polyester have lower erosion resistance than nano composites and the specimen (polyester +3% carbon fiber + 0.5% CNTs) has higher erosion resistance than other nano composites at 15cm, angle 30°, grin size of sand 400µm and 15 hour. Application of this work in protection of aircraft structure, turbine blades and pipes from erosion. The Taguchi experimental design ANOVA shows that the filler content factor has great effect on erosion rate of CNTs filled carbon, glass and Kevlar fibers reinforced unsaturated polyester resin.


Article
REMOVAL OF LEAD FROM POLLUTED WATER BY ADSORPTION ON BENTONITE CLAY PARTICLES

Authors: Mohammed Ali Rashid Hameed
Pages: 90-100
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This study investigates the capability of a certain type of natural Bentonite clay to remove the poisonous element; lead, from polluted water by adsorption phenomena on the clay particles at different temperature levels. Many high lead concentration synthetic solutions had been prepared in laboratory (24.3, 56.85, 146.55, 269.99, 284.72, 418.86, 465.61, 658.80 mg/L), and a volume of 250 ml from each solution being mixed with 2.5 g of Bentonite clay for a period of one hour at a certain temperature level (three levels were used, 20, 40, and 60 0C) and pH=7, until an equilibrium adsorption process being obtained, then the samples filtered through a porous paper, and the filtrate tested by atomic absorption technique to determine the remaining lead concentration. Very high removal efficiencies have been obtained (more than 98%), and the results were drawn on graphs to show the relations at test conditions. The above mentioned procedure was repeated using the same prepared lead solutions but mixed with 0.5 g of Bentonite clay and tested at temperature of 20 0C, and very good lead removals also were obtained. The adsorbed lead ions mass in mg, on Bentonite mass in gram (Me) were ranged from 2.387 to 65.848 at temperature levels of 20, 40, 60 0C and Bentonite clay dosage of 2.5 g per 250 ml of polluted waters ranged in initial Lead concentrations from 24 to approximately 700 mg/L, and Me from 24.808 to 202.938 for dosage 0.5 g at 20 0C at same lead concentration range. The Langmuir and Freundlich isotherm models for adsorption were used in analyzing the adsorption data and find their constants at different temperature levels to investigate if they can describe the obtained data well, Langmuir model was more representative of the data than Freundlich model. Bentonite clay would be very efficient in removing lead from industrial wastewater.


Article
PUNCHING SHEAR STRENGTHS OF HYBRID REINFORCED CONCRETE FLAT PLATE SLABS

Authors: Suha Rasheed Abass --- Haitham Jameel Abd
Pages: 101-115
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This study is conducted to test experimentally the punching shear of reinforced concrete flat plate slabs made with hybrid concrete (two types of concrete in two layers in specimens. Twelve test slab with ( 450×450×50 ) mm dimension The tested slabs have been. divided into four groups, each of which consisted of three slab specimens identical in size and shape but different in concrete type and steel bar reinforcement. All slabs are simply supported along the all edges and subjected to single point load applied at the center of gravity of each slab.Experimental results show that the use of hybrid concrete and high strength concrete improves the punching shear resistance and allows higher forces to be transferred through the slab-column connection. For slab specimen which fully cast using high strength concrete, the ultimate shear capacity increased by (40%) in comparison with the normal concrete slabs. While, for slab specimens cast using with hybrid concrete the ultimate shear capacity increased by (5%-45%) in comparison with the normal concrete slabs.This experimental results revealed that the ultimate load capacity increase with the addition of super plasticizers to the mix of concrete.


Article
EFFECT OF WASTE FOUNDRY SAND ON INDIRCT TENSIL STRENGTH OF ASPHALT MIXTURE

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Laboratory study for the use of recycled foundry sand to improve the performance of asphalt concrete mixture by replacement fine aggregate by waste foundry sand substitute for normal sand was conducted. The experimental work conducted for (4) different proportions (5, 15, 20 and 25)% as fine aggregate . (35) samples was prepared to examine the Marshall stability and flow and moisture damage for asphalt mixture. The obtained results indicate an increase of strength (IDT) for all mixtures than control mixture and higher resist to moisture damage with mixture has(FS (#50).The results showed improvement in behavior in terms of workability and durability and resistance.


Article
ELECTRICAL AND OPTICAL EFFECTS OF Ag DOPANT ON ZnO THIN FILM BASED MSM UV PHOTODETECTORS

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This paper presents the fabrication, characterization and performance analysis of Zinc Oxide (ZnO) and Sliver doped Zinc Oxide (SZO) based interdigitated Metal–Semiconductor–Metal (MSM) Schottky barrier UV photodetectors. The ZnO and SZO thin films were grown on p-type silicon (Si) (100) substrates by sol-gel and spin coating technique. The three devices were fabricated using silver (Ag) as Schottky contact photodetectors based on un-doped ZnO, SZO with (2% and 4%) doping ratios. The structural and morphological properties of ZnO and SZO thin films were studied using Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Atomic Force Microscopy (AFM). The optical and electrical properties for these films were studied using UV-visible and Hall effect measurements. With the applied voltage in the range of (-5 to 5 V) under dark condition, the values of the saturation current, barrier height, ideality factor, reach through and flat band voltages were extracted. Under UV illumination with different optical power levels ranging from (163.2µw -171.8µw) with a wavelength (254 nm), the values of the photo current, contrast ratio, responsivity, quantum efficiency, detectivity, and noise equivalent power were extracted. The SEM images showed a non-uniform distribution of the Ag dopants, these dopants were formed clusters and this clusters increased as the amount of Ag dopants increased. The mobility, carrier concentration, and roughness for the SZO films were increased as compared with undoped film. The optical band gap and the transmittance were decreased with increasing in the doping ratio. It was found that the saturation current decreased by a factor of 4, and 12 for the devices based on Ag doped ZnO (with 2% and 4 %) doping ratio. The sensitivity was significantly increased with increasing in doping ratio. This enhancement attributed to the roughness of the Ag doped ZnO thin films. Thus, this study revealed that the Ag doped ZnO films resulted in devices exhibiting better photoresponse as compared to those using un-doped ZnO thin films

Keywords

ZnO --- SZO --- ZnO:Ag --- MSM --- UV --- Sol-gel --- Ag.


Article
PERFORMANCE COMPARISON OF PROPOSED INTERLEAVER WITH DIFFERENT TYPES FOR PARALLEL TURBO CODE

Authors: Amjad Ali Jassim --- Wael A.H. Hadi
Pages: 143-156
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Interleaver type is important in parallel turbo code system. It’s responsible of improve code performance against additive white Gaussian noise AWGN. In this paper, introduce a new interleaver with its mathematical model. Study its performance as comparison with different interleavers, including random interleaver, QPP quadratic primitive polynomial interleaver as standard of LTE, chaotic interleaver and finally 2-D interleaver for burst error environment, Study the performance as simulation. The system takes in consideration also different modulation schemes including QPSK, 16-QAM and 64-QAM. Result comparison between different types summarized in performance BER curves and Tables.


Article
EVALUATING THE PERFORMANCE OF SUSTAINABLE INTERLOCKING CONCRETE BLOCKS MANUFACTURED FROM RECYCLED CONCRETE AGGREGATE

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This paper aims to investigate the possibility of using construction and demolition concrete wastes (C&D) in the production of recycled aggregate, which in turns will be used in the production of interlocking concrete blocks. Five groups of concrete mixtures have been prepared and tested with different proportions of recycled aggregates (0%, 25%, 50%, 75% and 100%). A series of tests (density, compressive strength, flexural strength and ultrasonic test) conducted on concrete cubes and concrete blocks to select best proportion of recycling concrete aggregate (RCA) to produce recycled aggregate concrete. The best proportion of RCA was 25%. This proportion was selected to evaluate the performance of interlocking concrete blocks pavement through studying the influence of block shape, thickness, laying pattern and jointing sand based on static plate loading test. The effect of load on the tested block pavement behavior was discussed. This behavior was characterized by deflection. It is found that shape and thickness of blocks have a significant influence on the behavior of interlocking concrete blocks pavement.

Keywords

Concrete --- Blocks --- Recycling --- Aggregate --- Deflection --- Density.


Article
RAINFALL INTENSITY EFFECTS ON Flexible PAVEMENT LAYERS

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The main objective of this work is to study of effect of rainfall intensity on the thickness of pavements layers of flexible pavement structure. This is using Maple 13 software for modeling of this problem and calculation the rainfall intensity and pavement infiltration. It was found that pavement infiltration increases with increasing rainfall intensity because of, the increase in the rainfall intensity caused an increase in the infiltrated water to the base and sub - base layers. Accordingly an increase in pore water pressure resulted which intends cause an increase in porosity and decrease of base and sub - base degree of compaction. Accordingly which leads to increase in time - to- drain, decrease in drainage coefficient for base and sub - base, and subsequently, request to increase their thickness. For flexible pavement, rainfall intensity 256 mm/hr is giving pavement infiltration, thickness and drainage coefficient 3.2m/day, 46 cm, 0.57 respectively and rainfall intensity 25 mm/hr is giving pavement infiltration, thickness and drainage coefficient 0.4 m/day, 18.5cm, 1.7 respectively. Drainage of accumulated water on pavement is accordingly drained rapid in as short time as possible due to minimize potential moisture damage to a pavement structure. It was found that soil type effects of moisture in pavement based on conditions of total saturation with loss of pavement strength from through affect the state of stress through suction (effective porosity) or pore water pressure and affect the structure of the soil through destruction of the cementation between soil particles because of, soil types difference in coefficient of permeability. Where, soil types have been used in this study Well-graded sand, Uniform dense sand and Fine-grain soil.


Article
CHALLENGES FACING CONSTRUCTION CONTRACTS IN IRAQ

Authors: Sultan Noori Al-karawi
Pages: 192-201
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This paper aims at exploring the most important challenges which are facing the construction contracts in Iraq, and trying to analyze these challenges from various aspects. Addition, we have put necessary recommendations to support this sector through some notes and appropriate plans. Challenges are classified into eleven major problems (Political Problems, financial problems, administrative problems, problems related to the tender documents (contracts, drawings), problems related to the specifications and materials adaptation (Quality), problems related to the contract parties themselves, problems related to the sector environment, problems related to the natural environment, problems related to the arbitrations and disputes solving, problems related to the technology uses, problems related to the career ethics). These varieties have been agreed upon through questionnaire that was made for a number of the relevant authorities about the challenges facing them in construction sector. Each one of them contains a minor problems, it will be discussed such as (Rates burning due to intense competition between contractors, awarding the bid to the lowest prices not to the most accurate, delaying paying owed payments by the owner, the changing value of currency exchange). Finally the recommendations and appropriate procedures to avoid these problems, it was (Price estimation before tendering, Awarding the nearest price, rejecting offers less than 25% of the estimated), and there is other recommendations we have mentioned in this paper for another more challenges.


Article
CONCENTRATING OF FELDSPAR FROM Al-SAMAWA SAND DUNE

Authors: Waleed R. Abdullah
Pages: 202-210
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This study was carried out to determine the possibility of upgrading feldspar from Al-Samawa sand dune deposit containing about 2 % Na2O and 1 % K2O. Two samples from the same location was tested by screening, employing, washing and disliming followed by magnetic separation then froth flotation by tallow amine acetate as a collector with poly propylene glycol and Ethyl diamine tetracetate (EDTA). The experimental results shows that a concentrate of commercial grade can be obtained in percent 5.54 % Na2O and 2.41 % K2O with a recovery of about 76.2 % and 77


Article
EFFECT OF WEB REINFORCEMENT ON SELF-COMPACTING REINFORCED CONCRETE CONTINUOUS DEEP BEAMS

Authors: Abdul_Qader Nihad Noori --- Adnan Falih Ali
Pages: 211-228
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The main purpose of this experimental study is to investigate the behavior and strength of self-compacting reinforced concrete continuous deep beams with and without web reinforcement. The program included cast and test of five beam specimens, in which the vertical and horizontal shear reinforcement were varied. All specimens had the same length, depths and main flexural reinforcement ratio and they were subjected to concentrated vertical loads only. It was found that the addition of vertical shear reinforcement with minimum ratio (ρv=0.25%) increases the both of cracking and ultimate loads by about 10%, When vertical shear reinforcement is increased by about 80% (from 0.25% to 0.45%) a noticeable increases in the ultimate load capacity is observed (the enhancement reached to 18.6%). When providing horizontal web reinforcement of (ρh=0.343%) in addition to the provided vertical shear reinforcement (ρv=0.25%), the cracking and ultimate loads increased by about (17.5% and 25%) respectively, while the previous ratios of the cracking and ultimate loads increased to (20% and 33%) respectively when vertical shear reinforcement increased to (ρv=0.45%).


Article
BIOSORPTION OF METHYELEN BLUE FROM AQUEOUS SOLUTION USING WASTES MICELIUM OF FUNGAL BIOMASS TYPE WHITE ROT FUNGI

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A waste dried mycelium of fungal biomass type white rot fungi was used to remove methylene blue dye from aqueous solution in batch mode. The equilibrium isotherm and kinetics have been investigated. Several parameters such as pH, contact time, dye concentration and biosorbent dosage were evaluated to determine the adsorption capacity and analyze the suitability of biosorption process. The equilibrium of the process was modeled using the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich(D-R) isotherms, while kinetic data were fitted by pseudo-first-order and pseudo-second-order kinetic models. Kinetic experiments indicated a better fit of process to a pseudo second order model, while the equilibrium isotherm data fitted well to Langmuir isotherm with maximum biosorption capacity of 23.69 mg/g and determination coefficient R2 equal 0.9909 compared with other isotherm models. The values of heat of sorption bT 0.6062 KJ/mol from Temkin model and mean free energy of sorption E 0.7847 KL/mol from D-R model indicated that the biosorption process was endothermic and physisorption in nature. The results show that dead biomass derived from waste of white rot fungi can be used as a good biosorbent material for removal of methylene blue from wastewater due to its low cost and high efficiency.


Article
EXPERIMENTAL STUDY THE EFFECT OF ABSORBING TUBE DIAMETER ON THE PERFORMANCE OF COMPOUND PARABOLIC CONCENTRATOR SOLAR COLLECTOR

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Abstract

A system of test rigs of solar collectors with the compound parabolic concentrator (CPC) have designed to study the performance namely (heat flux and efficiency) for all the solar collectors. The acceptance angle of the CPC taken at 45⁰ for all the solar collectors. The system used to study the effect of absorbing tube diameter on the solar collector performance. A halogen light used as energy source with different absorber tube diameters (0.75, 1, and 1.5) inch used. It has observed that the relationship between the time with the readings of water temperature inside the absorber tube and the performance results show that there are three regions for variation for all collectors. The variation for the water temperature, heat flux and efficiency in the first region varied sharply, in the second region varied gradually and in the third region remained constant. The compering performance results between the different solar collectors with different absorber tube diameters show that the collector with 1.5-inch absorber tube diameter gives the best performance than the others. Where the percentage increase in the temperature for the collector with absorber tube diameter of 1.5 inch compering with the other diameters ( 0.75 , 1 ) inch are (28.3 and 20.7) respectively While in case of heat flux are (69.8 and 53.4) and for the efficiency are (68.8 and 28).

Table of content: volume:22 issue:4