Journal of Duhok University 2021-01-25T11:03:27+00:00 Mr. Sidqi Mohammed Suliman Yassen Open Journal Systems <p>UoD Journal is a bi-annual academic journal.&nbsp;is a peer-reviewed, open access journal with eISSN: 2521-4861, pISSN:1812-7568</p> <p>Each Volume consists of three Sections:</p> <ul> <li>Humanities and Pure.</li> <li>Engineering Sciences.</li> <li>Agriculture and Veterinary&nbsp;Science.</li> </ul> MODELING AND STATISTICAL VARIATIONS OF LONG TERM OF MECHANICAL PROPERTIES OF CONCRETE MODIFIED WITH WASTE STEEL SLAG 2021-01-13T07:27:37+00:00 GONA I. NOORI LINA A. FAQEMAHMOOD SARKAN S. MOHAMMED AHMED SALIH <p>This study aims to evaluate and quantify the effect of steel slag (s), water-cement ratio (w/c), and <br>curing time (t) together on the compressive and tensile strengths of concrete. In this research, the results <br>were supported by more than 200 data collected from different research studies. The various water-<br>cement ratio used between 0.32 - 0.70 with a different steel slag percent up to 100% as a complete <br>replacement of fine aggregate (sand), and up to 90 days of curing time was considered. The strengths <br>range of modified concrete up to 36% replacement of compressive and tensile strengths were between 10-<br>70 MPa and 2-7 MPa respectively, and strengths of conventional concrete were between 10-62 MPa and 2-<br>6 MPa respectively. Concrete Mechanical properties with the use of steel slag, different range of w/c, and <br>curing time were correlated using different numerical models which show that both predicted and <br>experimented mechanical properties of conventional and modified concrete with steel slag are close to <br>each other referring to the coefficient of determination (R²) and root mean square error (RMSE). <br>Compressive (σc) and tensile (σt) strength of concrete as a function of w/c, curing time, and steel slag <br>using the Non-Linear Model (NLM) resulted properly.</p> 2020-12-28T16:35:03+00:00 Copyright (c) 2020 Journal of Duhok University MODELING THE BEHAVIOUR OF CHEMICAL RESISTANT CONCRETE MODIFIED WITH FLY ASH UNDER DIFFERENT PH ENVIRONMENTS 2021-01-13T07:58:17+00:00 RAZ RIZGAR HAYDAR AHMED SALIH MOHAMMED <p>Concrete is the main building unit used in infrastructure and buildings, including dams, swages, and <br>sewage pipes. The main problem in the concrete used in the sewerage pipe or the water treatment system <br>is the erosion when concrete becomes subjected to different pHs. This study’s objective is to evaluate and <br>model the effects of various pHs on plain concrete and concrete modified with fly ash. Water to cement <br>ratio and time of curing were taken as independent variables in the experiment. The main dependent <br>variables are the strengths of compression and tensile of the concrete. From the over 900 data collected, <br>the w/c was ranged between 0.3-0.5. The compression strength varied from 0-88.6 MPa and tensile <br>strength ranged from 0.5-5 MPa. Direct correlations between compression strength and w/c, curing time, <br>pH value and fly ash precentage were not found. From the Nonlinear Model ( NLM) parameters, fly ash <br>percentage has a positive effect on the concrete resisting the different pH values. However, FA% content <br>should not exceed 25% because it will cause the cement to lose its bonding qualities. FA might reduce the <br>rate of penetration of the chemicals and make the concrete resist the chemicals to penetrate further into <br>the interior of the concrete.</p> 2020-12-28T16:41:02+00:00 Copyright (c) 2020 Journal of Duhok University BADUSH DAM: PLANNED AND DESIGNED AS A PROTECTION DAM, NW IRAQ 2021-01-24T18:28:27+00:00 VAROOJAN K. SISSAKIAN NASRAT ADAMO NADHIR AL-ANSAR <p>Badush Dam is uncompleted combined earthfill and concrete dam, it is located on the Tigris River. The <br>dam is planned and designed to be a protection dam downstream of the already existing Mosul Dam to <br>protect population and infrastructure downstream of Mosul Dam. Thisa is attributed to the safety <br>concerns of Mosul Dam which suffers from severe karstification in its foundation due to the presence of <br>thick gypsum beds. The safety of Mosul Dam is a matter of debate since its construction and <br>commissioning in 1986. The construction of Badush Dam started in 1988 and suspended in 1991, although <br>(30 – 40) % of the dam was already built. The geological setting of Badush Dam is almost similar to that of <br>Mosul Dam. Therefore, the foundation of Badush Dam will suffer from the same problem which is <br>karstification because they are located on gypsum beds which are the same rocks under the foundations of <br>Mosul Dam. The thin inclined clay core and foundation treatment works indicate clearly that Badush <br>Dam is designed to have temporary nature which is to contain the volume of Mosul Dam wave (11 × 11<br>km3<br>) in case of collapse of Mosul Dam and to pass the wave downstream without flooding.</p> 2020-12-28T00:00:00+00:00 Copyright (c) 2020 Journal of Duhok University PROPOSED EFFECTIVE WIDTH CRITERIA FOR SLAB DECK BRIDGES UNDER MILITARY TRACKED LOAD 2020-12-28T16:58:08+00:00 BASSAM QASIM ABDULRAHMAN <p>For any slab deck bridge, the ultimate loading strength is obtained based on the distribution of that <br>loading to a slab effective width that recommended in the adopted specifications. In this study, a simplified <br>procedure with a design equation is presented. This procedure depends on the determination of the <br>moments developed in a slab deck bridge and thus the slab effective width that loading is distributed to. <br>The study employs the Iraqi military tracked load. The procedure applies to right, simply supported slab <br>deck bridges with and without edge stiffening beams based on the aspect ratio that represents the ratio of <br>the slab width to length. A 3D finite element analysis by a well-known programme ABAQUS was <br>conducted to analyse the whole bridges and to give the values of moments that will be used in the <br>derivation of an equation to calculating the slab effective width. Furthermore, a comparison between the <br>effective width of this study and the AASHTO and LRFD specifications was conducted. It is found that<br>this method gives some conservative results in comparison with AASHTO and LRFD standards because <br>other standards have some limitations, besides not to take in consideration all the parameters required</p> 2020-12-28T16:58:08+00:00 Copyright (c) 2020 Journal of Duhok University A COMPARISON BETWEEN UNMANNED AERIAL VEHICLE AND AERIAL SURVEY ACQUIRED IN SEPARATE DATES FOR THE PRODUCTION OF ORTHOPHOTOS 2020-12-28T17:12:05+00:00 FARSAT HEETO ABDULRAHMAN RAAD AWAD KATTAN SAMI MAMLOOK GILYANA <p>The Unmanned aerial vehicles (UAV) have become convenient for many applications such as the <br>production of 3D ground models, orthophotos, road maintenance and dam monitoring, etc. The aim of this <br>paper is to investigate the accuracy of the orthophoto obtained from UAV images compared to the existing <br>orthophoto generated from aerial survey conducted by Vossing German Company in Duhok city, 2011 <br>using GPS ground control point as a reference base. A digital elevation model (DEM) of the university <br>campus was created with the UAV vertical images. Low flight height of 80m was used with the rate of 70% <br>forward overlap and 40% side lap. An orthophoto is produced based on this DEM. To assess the accuracy <br>of UAV orthophotos and the existing orthophotos produced from aerial survey, 7 ground control points <br>(GCPs) were distributed and used for processing the orthophoto mosaic and DEM, 12 GCPs were used as <br>check points. The 19 GCPs were accurately measured using GPS-RTK. Discrepancy in horizontal position <br>of the GCPs measured on both orthophotos was obtained relative to the reference GPS base control points.<br>The UAV data were processed and analyzed using two softwares pix4D and Agisoft Photoscan. The RMS <br>errors obtained from both orthophotos is presented relative to the GPS base. Sub-centimetre accuracy for <br>horizontal position was achieved from the UAV orthophoto at low flight altitude.</p> 2020-12-28T17:12:04+00:00 Copyright (c) 2020 Journal of Duhok University STRENGTH, LOAD-DEFLECTION BEHAVIOR AND IMPACT RESISTANCE OF TWO-WAY SLAB FOR CONCRETE INCORPORATING WASTE ALUMINUM FIBERS 2020-12-28T17:33:54+00:00 SHEELAN MAHMOUD HAMA <p>This research investigated about the effectiveness of waste aluminum results from waste cans <br>of gassy drink, as fibers in concrete. strengths, load-deflection behavior under flexural load and <br>impact resistance under low velocity repeated impact load were investigated. Two length of <br>fibers were examined 40 mm and 20 mm for 0%, 0.5%, 0.75% and 1% fibers content. Results <br>showed that compressive strength has inconsiderable affected by adding fibers while splitting <br>tensile strength, modulus of rupture and impact resistance for concrete incorporating aluminum <br>fibers especially for 0.75% and 4-mm fibers have clear improvement. Compared to experimental <br>results, ACI equation underestimated the tensile strength of fiber concrete. Load –deflection of <br>beam with fibers showed a more ductile behavior at failure under flexural load compared to <br>reference one. Bond strength improved by adding aluminum fibers. Slabs that incorporating <br>aluminum fibers showed a higher energy absorbed, less deflection and smaller cracks width at <br>failure than the one without fibers under impact loads. From results, one can see that mixes with <br>0.75% fibers showed a best performance compared with other mixes. Finally, the 40 mm fiber <br>was more effective in improvement in concrete resistance than 20 mm fiber length.</p> 2020-12-28T17:33:54+00:00 Copyright (c) 2020 Journal of Duhok University FACTORS OF DELAY IN PUBLIC CONSTRUCTION PROJECTS IN THE KURDISTAN REGION OF IRAQ 2020-12-28T19:04:59+00:00 HNAR ALI KARIM AL-JAF YOUSIF SALAM SAEED <p>Delay in public construction projects sector has become a phenomenon in construction industry in the <br>developing countries. Iraqi Kurdistan Region has deprived of many valuable scientific and exclusionary <br>researches have studied delay in this sector for decades, due to the fact that, projects in this region are not <br>subjected to the same standards and administrative laws as those of the central government of Iraq. <br>Therefore, determining and ranking the main delaying factors of the PCPs in the Kurdistan region of Iraq <br>is the main objective of this publication, by reviewing and presenting previous publications in this regard <br>and conducting a survey, involving the most important factors related to the main participants in the <br>construction industry processes (client, contractor, consultant) in addition to the external factors, that <br>affect the implementation of public construction projects, Responses were collected and analyzed to obtain <br>the key delay factors by finding the frequency, impact and importance indexes of the four groups (client, <br>contractor, consultant and the external factors). The results showed that out to twelve top ranked factors, <br>six contractor related factors, three client related factors, two external related factors and one consultant <br>related factors.</p> 2020-12-28T19:04:59+00:00 Copyright (c) 2020 Journal of Duhok University INTEGRATING A SET OF LEAN CONSTRUCTION TECHNOLOGY TO BUILDING INFORMATION MODELLING 2020-12-28T19:14:51+00:00 IHSAN ALI HUSSEIN AL-SARRAY YOUSIF SALAM SAEED AHMED ADIL NAJI <p>Technology has a great impact in managing and implementing highly desired complicate design <br>construction projects, this paper attempted to address a set of synergies between Lean Construction <br>Technologies (LCTs) and Building Information Modeling (BIM) to provide the researchers with a fully <br>comprehensive idea about the impotence of the integration. Through reviewing and presenting of the <br>published papers which presented the integration of one or two lean technology concepts integrated to <br>building information modeling in accordance to the studied cases in one paper, this paper will provide the <br>researcher, developer, and constructing companies with many studied cases presented some of the most <br>important Lean technologies in this field. These technologies are; Last Planer System (LPS); KanBIM; <br>VisiLean; Just-In-Time (JIT); Value Stream Mapping (VSM). Also, this paper suggested the possibility of <br>integrating a 5S technology to BIM for a future study.</p> 2020-12-28T19:14:50+00:00 Copyright (c) 2020 Journal of Duhok University ANALYZING THE PARAMETERS AFFECTING THE QUALITY OF REFUSE DERIVED FUEL PELLETS DERIVED FROM MUNICIPAL SOLID WASTE 2020-12-28T19:30:32+00:00 MARYAM MUAYAD QABAS ABBAS ZAHRAA ABDULKADER <p>One of the major factors that play a role in threatening our climate maintenance is the non-ecofriendly<br>energy production and finding an alternative to this is essential. Refuse-derived fuel (RDF) is an <br>alternative process for non-ecofriendly energy production in which fuel is produced from various types of <br>local waste, including municipal solid waste (MSW). It diverts the landfill waste into a source of energy <br>supplier. This review paper examines the parameters that affect the quality of the <br>Refuse-derived fuel (RDF) that is derived from municipal solid waste (MSW) by reviewing prior studies <br>from multiple sources; experiment-based research papers. The examined parameters from the collected <br>data which included the moisture content, the ash content, Calorific value, Sulfur content, Chlorine <br>content, Carbon content, as well as the content of heavy metals; Cadmium (Cd), Chromium (Cr), Nickel <br>(Ni), Silver (Ag), Zinc (Zn), Lead (Pb), Copper (Cu), and Arsenic (As) were descriptively analyzed in <br>comparison to the typical contents found in the Refuse-derived fuel (RDF) as these typical contents <br>determine the quality of these pellets for producing energy. Some of the collected data for some <br>parameters fell within their typical range. Yet, some did not.</p> 2020-12-28T19:30:32+00:00 Copyright (c) 2020 Journal of Duhok University SEISMIC VULNERABILITY ASSESSMENT OF REINFORCED CONCRETE STRUCTURES IN KURDISTAN REGION-IRAQ 2020-12-29T17:51:24+00:00 MAND ASKAR KAMIRAN ABDUKA LAWEND ASKAR <p>Earthquakes are one of the most destructive natural disasters that cause losses of life, damage to <br>infrastructure and economic issues. Therefore, seismic risk assessment is essential for disaster mitigation, <br>disaster management, and emergency preparedness. Seismic vulnerability is one of the major factors for <br>evaluating the risk of earthquakes on reinforced concrete (RC) buildings. Seismic vulnerable RC buildings <br>are buildings located in a seismic region and either designed with an outdated design code or designed <br>without consideration for seismic activity. In the Kurdistan region of Iraq, most of the existing RC <br>buildings do not meet the typical current seismic standard requirements as the region was expected as <br>non-seismic region and followed the Iraqi seismic zone which considered as a low seismic region, therefore<br>these type of buildings is expected to suffer extensive damage during strong earthquakes. Vulnerable RC <br>buildings should be assessed in order to prevent future damage and new designed buildings need to meet <br>such codes. Previous studies, conducted assessment of four to six stories structures in order to evaluate <br>seismicity and to increase ductility of the evaluated structures based on member size. In this research, an <br>existing 8-storey RC building, located in Duhok governorate- Kurdistan region of Iraq, is redesigned and <br>evaluated. SeismoStruct V6.5 software was utilized for the purpose of simulating ductility and detailing<br>for the existing structure using pushover analysis. The ductility of the existing and the proposed <br>redesigned buildings then evaluated by obtaining inter-story drift and displacement based on capacity <br>curve. The original design is further evaluated in terms of reinforcement ratio and detailing by <br>redesigning the existing building in accordance with the ACI code 318, 2014 and using ETABS software <br>version 9.7 for analysing. Nonlinear static pushover analysis is used for seismic performance evaluation. <br>Inelastic static analysis procedures include capacity spectrum method and displacement coefficient <br>method. The structure is then analyzed to observe the yielding of the members and the adequacy of the <br>structural strength. The extent of damage experienced by the structure at the target displacement <br>represents the damage that would be experienced by the building when it is subjected to an earthquake. <br>As a conclusion, the redesigned structure showed 30% increasing in displacement when loaded in x-<br>direction based on both ultimate and calculated base shear while the increase in displacement was around <br>10% when loaded in the y-direction. This displacement increase led into improving the ductility in the <br>redesigned structure.</p> 2020-12-29T17:51:24+00:00 Copyright (c) 2020 Journal of Duhok University SIMULATION OF TUNNEL LINING AND SURROUNDING ROCK MASS RESPONSE TO CONSTRUCTION LOADS 2020-12-29T18:22:40+00:00 JAAFAR A. MOHAMMED <p>The major design parameters related in tunnel engineering are loads, tunnel dimensions, geological <br>and geotechnical properties of the ground surrounding the tunnel, which controls stresses and <br>deformation of this underground structure. The effects of static loads during tunneling with shield Tunnel <br>Boring Machine (TBM) on the rock mass and segmental concrete lining are considered. Applied static <br>loads are (self-weight, drilling or excavation pressure, jack thrust, shield external pressure and segment <br>external pressure). A comparison of the results of maximum total displacement and principal stresses of <br>soft rock for different tunnel diameters including (D = 4, 6, 8, 10, 12 and 14 m) is performed. Tunnel lining <br>of a circle tunnel were assumed to behave in a simple linear elastic way. Rock mass is assumed to be <br>Isotropic, homogeneous and elastic rock in this modelling. The numerical analysis has been simulated and <br>evaluated for each models separately. The thickness of tunnel lining for all models was assumed as 30 cm. <br>The main concluding points of this study are to analyze the behaviour of tunnel lining and the <br>surrounding rock under static loads during the construction processes using numerical modeling.</p> 2020-12-29T18:22:40+00:00 Copyright (c) 2020 Journal of Duhok University EVALUATING DRIVER BEHAVIOR IN YELLOW INTERVAL AT SIGNALIZED INTERSECTIONS 2020-12-29T18:38:14+00:00 NASREEN AHMED HUSSEIN <p>Signalized intersection is one of the most popular type of control at intersections in urban areas. Study <br>of the elements of this type of control is vital to reduce accident rate, improve performance, and decrease <br>delay. Yellow period is one of the parameters which has influence in performance of these type of<br>intersections specially accident rate. At the indication of yellow interval, when drivers approach a <br>signalized intersection, they need either to proceed and cross the intersection or stop safely before the stop <br>line. The objective of this study is to identify significant factors that impact driver’s decision at yellow <br>interval in dilemma zone. Data was collected using questionnaire survey and video recording technique at <br>two signalized intersections in Duhok city for the period of peak and off-peak hours. Assessing the effects <br>of influential factors including vehicle speed, distance to the stop line and vehicle type on driver behavior <br>has been achieved through observations of trends from graphs and statistical analyses using Logistic <br>regression. Results of questionnaire survey indicate that the younger drivers of (18-30) years are more <br>aggressive and end up running a red light. Moreover, the results of trend analysis showed that number of <br>drivers who run the yellow decreases as the distances to stop line increases and dilemma zone at peak <br>hours are located nearer to the stop line as compared to off peak hours. The lower green time to cycle time <br>ratio in four leg intersection increased the probability of crossing the intersection instead to wait for <br>another green period. Results of all three parts show that both the vehicle speed and distance to the stop <br>line are significant factors affecting driver decision.</p> 2020-12-29T18:38:14+00:00 Copyright (c) 2020 Journal of Duhok University A COMPARATIVE STUDY OF REAL FULL SCALE GROUND RECTANGULAR WATER TANK IN DUHOK CITY 2020-12-29T20:17:15+00:00 YAMAN SAMI SHAREEF AL-KAMAKI RONDIK ADIL JAFAR GULAN BAPEER HASSAN ALAA ALSAAD <p>It is well known that facilities like storage reservoirs and tanks have a great priority as it serves mainly <br>for portable drinking water for a huge population. In general, water tanks are designed based on their <br>shapes and ground positions. In this comparative study an attempt is made to consider a rectangular <br>reinforced concrete (RC) ground water tank of a real full scale as a case study in Duhok city. Two identical <br>surface water tanks of a 9000 cubic meter capacity and having 50 mm joint in between have been <br>undertaken in this study. The tank were analyzed and design manually based on working stress method to <br>ensure that it is crack-free to avoid any leakage. The outcomes were then evaluated using ETABS, <br>SAP2000 and SAFE software by performing three dimensional (3D) analyses. The mat foundation and top <br>slab of the tank were analyzed using SAFE software. The study involves calculations of bending moments, <br>shear forces, and reinforcement. The tank walls are subjected to dead load and hydrostatic load due to <br>water. A parametric study has been undertaken also by considering water level and soil bearing capacity<br>as variables in this investigation. A good agreement has been obtained in this comparison. It may be <br>deduced that a design software can be used accordingly with a reasonable degree of accuracy than manual <br>calculations. This can maintain a reasonable cost and avoid human errors in any structure which is a <br>critical local and global issue nowadays.</p> 2020-12-29T20:17:14+00:00 Copyright (c) 2020 Journal of Duhok University PRACTICAL FIELD INVESTIGATION TO INDICATE COMMON FLEXIBLE PAVEMENT DISTRESSES THAT OCCUR IN THE MALIK MAHMOOD RING ROAD-SULAIMANIYAH CITY 2020-12-29T20:27:51+00:00 HEMN UNIS AHMED WRYA A. ABDULLAH SARDAR MAJEED OMAR YOUNIS M. ALSHKANE ARIAN OMER MAHMOOD <p>When the top layer of the road defects with time, it is called distresses of the pavement. The causes for <br>this pavement distress vary as most of the flexible pavement structures are subjected to repeated heavy <br>traffic loadings and high temperature changes which causes pavement cracking, deformation and <br>deterioration. The existence of these defects on the road surface makes it uncomfortable and unsafe for <br>the users, therefore, it should be determined and treated in appropriate ways. This research is conducted <br>to identify the most common types of flexible pavement distresses which occur in the Sulaimaniyah city, <br>Iraq, and to find out different reasons behind those distresses along with proposing suitable ways for their<br>maintenance. The data collection was done in the Malik Mahmood ring road in the Sulaimaniyah city. <br>The work study is carried out in locations that are subjected only to passenger cars and heavy truck <br>loadings. Field surveying shows that the most common flexible pavement distresses occurred in the <br>selected area are various types of cracking, rutting, corrugation, shoving, patches and potholes. Finally, <br>recommendations on maintenance method are provided to guide the Sulaimaniyah governorate and <br>municipality on solving the distresses and to have a promising repairing practice for the road network</p> 2020-12-29T20:27:51+00:00 Copyright (c) 2020 Journal of Duhok University INVESTIGATION ON THE SPECIFIC ABSORPTION RATE (SAR) IN A 3D HUMAN HEAD MODEL EXPOSED TO ELECTROMAGNETIC RADIATIONS 2020-12-29T20:34:05+00:00 FAYYADH H. AHMED MARTIN FIEBICH <p>Exposure human tissue to electromagnetic radiation (EM) from radio wireless frequencies causes many <br>negative health effects. The assessment of the absorbed EM by human tissue depends on the Specific <br>Absorption Rate (SAR) factor. In this paper, a square patch antenna (SPA) is designed to be a source of <br>EM radiation, and optimized to operate at several applicable frequencies, such as GSM 1800, IEEE 802.11 <br>WLAN standard 2.4 GHz and 5.3 GHz bands, and 3.2 GHz WiMAX band. The radiated EM by the SPA <br>antenna is evaluated in a 3D human head model or Specific Anthropomorphic Model (SAM), which <br>consists of two layers, the outer shell (1.5 mm thickness) and filled with tissue simulating liquid (TSL). <br>The investigation involved four aspects, first the distance between the SAM and the EM source has been <br>moved between 0 mm to 50 mm, second for the specific distances (0 mm, 15 mm, 30 mm, and 45 mm) the <br>frequency of EM source has been changed among 1.8 GHz, 2.4 GHz, 3.2 GHz, and 5.3 GHz. Third, the tilt <br>angle (θ) between the SAM and the antenna has been shifted from 00<br>to 900<br>. Finally, the antenna <br>encasement (2 mm thickness plastic material) was removed and the procedure in the first step is repeated <br>to investigate the effect of encasement on the SAR reducing. The results reveal that there is an inversely <br>proportional relation between SAR and distance, SAR and tilt angle. Besides, the antenna encasement has <br>a large impact on attenuating SAR value, while the SAR is directly proportional to frequency. All SAR <br>evaluations were performed by CST-2014 Microwave studio simulator which is built on the <br>Finite-Difference-Time-Domain (FDTD) principle. All calculations are achieved over 1 g and 10 g of mass <br>tissue averaging and according to IEEE/IEC 62704-1 standards.</p> 2020-12-29T20:34:05+00:00 Copyright (c) 2020 Journal of Duhok University EFFECT OF GRAVEL DUST AND LIMESTONE DUST ON GEOTECHNICAL PROPERTIES OF CLAYEY SOIL 2021-01-02T17:53:04+00:00 HUSSEIN JALAL ASWAD HASSAN SHAAFAN ABDULLAH TAHER SHEYAN ALYOUSIFY <p>Gravel dust and limestone dust are types of solid waste materials that are obtained from the crusher <br>plant. These materials are dumped-off in high amount causing a negative impact on the environment and <br>creating serious hazards on health. As the construction activities are increased in developing countries, the <br>demand of crushed gravel and crushed limestone for roads, airfields, railway ballast, buildings and <br>concrete work are increased. This study attempted to investigate the effect of gravel dust and limestone <br>dust on geotechnical properties of clayey soil. Testing program including Atterberg limits, compaction,<br>CBR and free swell tests, were performed on clay with the dust at varying amounts (10, 20, 30 and 40%). <br>The results showed that the Atterberg limits of clay decrease in proportion to increases in the amount of <br>dust. The increase in gravel dust contents decreased the compaction characteristics of clay. However, the <br>MDD increased and OMC decreased with increase in limestone dust contents. A series of soaked CBR <br>tests were conducted on the clay-dust mixtures of gravel dust and limestone dust. The dust was mixed with <br>the clay of different weight percentages. The results showed a general increase in the CBR value of clay <br>with the addition of dust. The CBR value increased gradually with the gravel dust content. The maximum <br>CBR was obtained at optimum limestone dust content, approximately 20%. Swelling percentages <br>decreased gradually with the dust content. The tests results revealed that it is possible to use gravel dust <br>and limestone dust for improving the properties of clayey soil.</p> 2021-01-02T17:53:03+00:00 Copyright (c) 2021 Journal of Duhok University INVESTIGATION OF THE USE OF SCRAP TYRES AS SOIL REINFORCEMENT 2021-01-02T18:01:45+00:00 SHAAFAN ABDULLAH TAHER HUSSEIN JALAL ASWAD HASSAN ASAAD FARAMARZI <p>Waste tyres, which are produced in every society in numbers that are increasing annually, are <br>impacting the environment and causing serious problems. These materials possess exceptional properties <br>that can be reused as reinforcement materials in the geotechnical engineering industry. This study <br>investigated the effects of tyre shreds that were randomly mixed with sand and clay to enhance their <br>engineering properties. An Atterberg limits analysis, as well as compaction and odometer tests, were <br>performed on china clay with scrap tyres of varying weights (10, 20, 30 and 40%). The results show that <br>the Atterberg limits of clay decrease in proportion to increases in the volume of tyre shreds. The <br>compaction characteristics of clay decreased with increased tyre-shred contents of 2–6 mm and 12 mesh. <br>Compression and recompression indexes increased gradually with the tyre-shred content of 12 mesh. A <br>series of direct shear strength tests were performed on the sand-shredded tyre mixtures of Levenseat sand <br>and concrete sand using a direct shear box of 10 cm x 10 cm. Two relative sizes of shredded tyres, 12 mesh <br>and 2–6 mm, were mixed with sand of different weight percentages. The results showed a general increase <br>in the shear strength parameters of both types of sand with the addition of the shredded tyres. The <br>maximum shear strength was obtained at optimum shredded tyre content, approximately 20% for the 2–6 <br>mm shreds and 15% for the 12-mesh shreds. The results showed that it is possible to use shredded tyres in <br>geotechnical applications</p> 2021-01-02T18:01:45+00:00 Copyright (c) 2021 Journal of Duhok University COMPARATIVE STUDY OF USING FLEXIBLE AND RIGID PAVEMENTS FOR ROADS: A REVIEW STUDY 2021-01-02T18:15:38+00:00 SHAAFAN ABDULLAH TAHER SHEYAN ALYOUSIFY HUSSEIN JALAL ASWAD HASSAN <p>Roads have become an essential measure and symbol of the development of societies. Road <br>construction projects are essential infrastructure facilities for any countries, and high amounts of the <br>budget allocated every financial year by decision-maker. The construction of road required researches,<br>good plan and design, and excellent builders to discover innovatively and cost-effective engineered <br>products to satisfy the increasing request that would economize the construction as well as increasing<br>durability. Despite the economic factor, this study will present a comparative review on the suitability of <br>using rigid and flexible pavements in road depending on traffic, climate, foundation, life cost, materials, <br>maintainability and safety consideration. The reviewed studies show that the design of concrete pavement <br>is based on flexural strength whereas in the asphalt pavement is based on load distributing characteristics <br>of the component layers. The concrete pavement life is slightly longer than asphalt pavement. The initial <br>cost of the flexible pavement less than the cost of rigid pavement but conversely, the cost of flexible <br>pavement is more than the rigid pavement with the long run because of the incurring costs of maintenance. <br>The rigid pavement has better ability and durability to hold a shape against traffic and difficult <br>environmental conditions than flexible pavement.</p> 2021-01-02T18:15:38+00:00 Copyright (c) 2021 Journal of Duhok University CORRELATION OF SHEAR WAVE VELOCITY WITH SPT-N FOR A TOWER- BUILDING SITE AT ERBIL CITY 2021-01-02T19:34:15+00:00 AHMED MOHAMMED HASAN YOUSIF ISMAEL MAWLOOD AZAD A. AHMED HAWKAR HASHIM IBRAHIM <p>Measurement of shear wave velocity (Vs) plays a crucial role in ground movements around <br>geotechnical structures such as building foundations in the urban area and tunnels. Basically, measuring <br>Vs often requires when seismic properties of soils are essential to be calculated, such as elastic shear <br>modulus. Multichannel analysis of surface wave (MASW) is one of the seismic methods which employs <br>surface waves to measure Vs. It is often not available along with site investigation due to high cost, <br>complicated technical analysis, noise pollution, space constraints, etc. Hence, it is essential to predict Vs <br>through correlating it to other soil parameters such as standard penetration test blows count (SPT-N). <br>Therefore, the main focus in the current study was to correlate between Vs and SPT-N using an empirical <br>equation likely applied for clay soils. A complementary subsoil investigation was performed of a tower-<br>building at Erbil City, including SPT-N values for three boreholes and their corresponding MASW <br>measurements. These data were, in turn, used to estimate Vs from corrected SPT-N. The currently <br>proposed equation compared with the existing ones in the literature. The comparison shows that the <br>proposed equation predicts the values of Vs as good as those available in the literature for both of the <br>datasets in the current and the previous studies.</p> 2021-01-02T19:34:15+00:00 Copyright (c) 2021 Journal of Duhok University AIR POLLUTION ESTIMATION IN ERBIL CITY CENTER USING BOX MATHEMATICAL MODEL 2021-01-02T19:42:27+00:00 SALAH FARHAN A. SHARIF HASSAN ABDULWAHAB ANJEL <p>Erbil city center, topographically, is a low basin surrounded by highlands from all sides and is <br>characterized as relatively humid weather during the autumn, winter and spring days. These factors with <br>the increasing number of cars in the street, added to the vast number of private electric generators using <br>poor quality of fuels caused the high level of air pollution in the basin and black clouds over the city. In <br>this paper, the concentration of accumulated pollutants was estimated at different points by using a <br>known mathematical model called “Fixed Box Model”. This mathematical model was developed and <br>processed, by researchers, using computer mat lab to calculate the concentrations of pollutants in Erbil's <br>city center at any time of the day in different levels. The collected data of the contributing cars, trucks and <br>electric generators were processed by the developed model and shows that the accumulated pollutants, on <br>the breathing level 4 hours after the morning rash time, were as follows: NOx= 300 µg/m3<br>, HC= 54 µg/m3, <br>CO= 350 µg/m3<br>, PM2.5= 9 µg/m3<br>, PM Brake= 0.15 µg/m3<br>and CO2= 2.04*104 µg/m3 which may often be <br>the reason for the black cloud appearing over Erbil’s city center.</p> 2021-01-02T19:42:27+00:00 Copyright (c) 2021 Journal of Duhok University THE POSSIBILITY OF USING JERK PARAMETERS AS SEISMIC INTENSITY MEASURE 2021-01-02T19:53:33+00:00 ABDULHAMEED A. YASEEN MEZGEEN S. AHMED YAMAN S. S. AL-KAMAKI <p>It is a common procedure to use a single parameter because of its simplicity to represent the seismic <br>action in a particular region and describe its complex nature. This single parameter generally is known as <br>ground motion intensity measure IM. The time derivative of acceleration, commonly known as jerk, is met <br>in a limited number of such studies and specifically in earthquake engineering. For that purpose, this <br>paper presents a study on the performance of using seismic jerk as ground motion IM. Several typical RC <br>frame buildings of different numbers of stories were selected. The nonlinear time-history analysis is <br>performed while the buildings are exposed to twenty-seven natural earthquake records using ETABS <br>software. The maximum displacement at the top of the building is selected as the structural response <br>parameter. Several widely used IMs were defined in addition to the jerk and its based parameters. After <br>performing a large number of nonlinear analyses and applying machine learning, best feature subsets that <br>present relation between response parameter and considered intensity measures were obtained. For <br>structures with low nonlinearity in behavior, jerk- based parameters were shown to be effective.</p> 2021-01-02T19:53:33+00:00 Copyright (c) 2021 Journal of Duhok University PRE-PRESSED AND BURNT SANDY CLAY TILES USED TO COVER EXPOSED CONCRETE ROOFS AS A SUSTAINABLE ALTERNATIVE 2021-01-04T18:03:29+00:00 SALAH FARHAN A. SHARIF A’ADEL HATAM NAWAR ABDULELAH HAMEED YASEEN <p>Traditional method of concrete ceiling used in Iraq is composed of covering the steel reinforced <br>concrete roofs with a thin layer of asphalt covered by 7-15cm river sand, as a minimum, and then covered <br>with concrete slabs 80x80x5 cm which are both, heavy materials and highly conductive causing severe <br>problems of cost, cooling and heating tasks. In this research work a sustainable construction materials <br>were studied to replace those conductive and unsustainable materials. A layer of putty clay with straw is <br>used as a mortar on the asphalt coated concrete roof surface and then covered with tiles made of burned <br>sandy clay. Pre-pressed Burnt Sandy Clay Tiles (PBSCT) were developed, produced and tested by the <br>researchers. Used raw materials for slab manufacturing were withdrawn from Al-Anbar western desert. <br>Chemical and physical analysis reviled that the best selected samples were from A'amj &amp; Al-Husayniat <br>quarries. Test results showed that higher silicon content, lower magnesium, potassium and sodium <br>compounds leads to better slabs specifications. Higher compressive strength was obtained with higher <br>burning temperatures as results showed 3.7 (M Pa) was the maximum reading for A'amj &amp; Al-Husayniat <br>clays with burning temperature of 1320 oC. Breakdown test shows that the max result was 1.43 (M Pa) at <br>the same temperature.</p> 2021-01-04T18:03:29+00:00 Copyright (c) 2021 Journal of Duhok University NUMERICAL ANALYSIS OF IN-PLANE BEHAVIOUR OF MASONRY INFILLED RC FRAMES USING MACRO AND MICRO MODELS 2021-01-04T18:14:24+00:00 KAMARAN MOHAMMED KAREEM HUNAR FARID HAMA ALI HIWA HAMED SHARIF BEDAR RAUOF HASSAN FARAYDON HAMA RASH W. MAHMOD <p>A number of simplified methodologies have been proposed aiming at preparing numerical tools <br>suitable for engineering application, to predict the nonlinear seismic behavior of infilled frame structures. <br>In this paper, a 2D discrete macro element model (DMEM) for the simulation of the in-plane behavior of <br>RC frames with infill walls, is presented, validated with an experimental result that investigate the <br>influence of infill masonry, and evaluated with a proposed Finite Element model (FEM). In this model, the <br>frame members are modeled by beam-column elements with lumped plasticity, while the infills <br>contribution are modeled by plane discrete-element. As an extended study, a 2D prototype of multistory <br>frame building, for which the results of pseudo dynamic tests are available, is investigated. The ability of <br>the considered DMEM to predict the in-plane behavior of infill masonry elements is investigated, the <br>merits and drawbacks are highlighted.</p> 2021-01-04T18:14:23+00:00 Copyright (c) 2021 Journal of Duhok University NATURAL ADMIXTURE AS AN ALTERNATIVE FOR CHEMICAL ADMIXTURE IN CONCRETE TECHNOLOGY: A REVIEW 2021-01-04T18:21:16+00:00 HERSH FAQE HOSHANG DABAGHH AZAD MOHAMMED <p>The use of chemical admixtures in concrete is a common practice in modern construction. Although <br>chemical admixtures improve the properties of concrete but also create leaching problem and they are <br>responsible for environmental pollution. The Impact of chemical admixture on environmental can occur <br>when chemical admixtures are exposed to the environment or when dumping concrete granulate <br>containing admixtures after the demolition of a structure or when concrete granulate is used as gravel <br>replacement in construction and as the concrete admixtures are very readily soluble in water, hence <br>create an environmental problem due to leaching. This paper presents a critical review of several natural <br>materials used in concrete as an admixture that influences the mechanical and durability properties of <br>concrete. This kind of admixtures can be considered as an eco-friendly one with regard the impact on the <br>environment and of low cost compared with the chemical admixture</p> 2021-01-04T18:21:16+00:00 Copyright (c) 2021 Journal of Duhok University FECAL SLUDGE MANAGEMENT OF DUHOK CITY AND 4 IDPS AND REFUGEES CAMPS 2021-01-04T19:49:34+00:00 SHAWKAT AHMED KOCHARY <p>This study aims to assess the condition of fecal sludge management (FSM) services of non-sewered <br>(on-site) sanitation systems in Duhok city and Chamishko, Kaparto2, Sharia IDPs and Domiz1 refugees <br>camps. Duhok city was selected as a case study while other locations were selected for their formally <br>temporal status besides their difference in location, size, and level of existing proper service delivery. Shit <br>flow diagrams (SFD) for on‐site sanitation systems of interested areas were produced to identify the <br>service outcomes and where improvements are needed to eliminate the negative impacts of FS on both <br>public health and the environment. The study revealed that sanitation delivery services were at very good <br>level in Kabartu2 camp as it has a wastewater treatment plant WWTP of 900 m3<br>/day capacity and in <br>Sharia camp as it has a (Package Sewage) treatment plant of 1760 m3<br>/day capacity. In Domiz1 camp, the <br>sanitation services were at poor level even though 25% of its generated wastewater transports to <br>Kabartu2 WWTP for treatment. Similarly, the sanitation service level in both Duhok city and Chamishko <br>camp were poor and very poor respectively where urgent improvements are needed. Recommendations <br>were proposed to the decision makers of local authority to take proper actions.</p> 2021-01-04T19:49:34+00:00 Copyright (c) 2021 Journal of Duhok University REFLECTIONS OF HALABJAH EARTHQUAKE EFFECTS ON THE STRUCTURAL BUILDING DAMAGES IN HALABJAH AND DARBANDIKHAN 2021-01-04T19:56:42+00:00 WRYA ABDULLAH SERWAN KHORSHEED RAFIQ YOUNIS M. ALSHKANE <p>Earthquakes hit the earth on daily basis with different intensities. An earthquake of M 7.3 hit <br>Halabjah on 12th of November 2017 and caused structural damages in both Halabjah and Darbandikhan. <br>This paper investigates the reflections of seismic effects on the most structural damages found in the areas<br>presenting a thorough site investigation on the possible reasons behind the building failures and collapses <br>and specifying the probable errors in their constructions and designs. Additionally, some of the most novel <br>techniques of retrofitting are proposed to rehabilitate the damages in the buildings. After the investigation, <br>it is deduced that, most of the structural failures can be attributed to lack of knowledge about lateral loads <br>and not considering them in the design and construction of the buildings in those vicinities. Further, the <br>construction level of the buildings can be considered as unsatisfactory in the affected areas for some <br>serious problems mentioned in detail in the paper. Therefore, most of the buildings needed immediate <br>rehabilitation and some of the most modern methods are proposed in doing so. As a result, it is proved <br>that a proper balance has to be guaranteed between strength, stiffness and ductility in designing buildings <br>to withstand lateral forces from an earthquake.</p> 2021-01-04T19:56:42+00:00 Copyright (c) 2021 Journal of Duhok University A COMPARISON BETWEEN INTERPOLATION METHODS FOR MORE ACCURATE ELEVATION SURFACE USING GNSS AND GIS 2021-01-04T20:13:44+00:00 FARSAT HEETO ABDULRAHMAN SOLEIMAN FOROUGHI SARHAT MUSTAFA ADAM <p>Elevation surface is a fundamental element of spatial data that can be employed to perform a variety <br>of geostatistical and spatial analyses. On this basis, this paper presents the assessment of elevation <br>surfaces interpolation methods such as Inverse Distance Weighting (IDW), Ordinary kriging, and Local <br>Polynomial Interpolation (LPI). There are three scenarios for achieving this purpose by examining it in <br>three different areas: mild slope area, steep slope area and combined case. The dimension of each tested <br>area is decided to be 100*100 m with 121 survey points for each. The ellipsoidal height of survey points are<br>measured by the Global Navigation Satellite System (GNSS) receiver exploiting the real-time kinematic <br>(RTK) technique. All survey points are transferred to Arc GIS environment for generating elevation <br>surfaces and conducting interpolations. Interpolated pixels of surfaces are then compared with the trusted <br>data collected with GNSS receiver in RTK mode. The result revealed that the total Root Mean Square <br>(RMS) error for kriging interpolation in the steep area is around 26 cm, whereas RMS for LPI <br>interpolation in the flat area found to be approximately 8.0 cm. The evaluation outcomes can be utilized to <br>understand the influence of the slope on interpolation methods as well as to select the most appropriate <br>method according to the ground relief.</p> 2021-01-04T20:13:44+00:00 Copyright (c) 2021 Journal of Duhok University PERCEPTION OF RESIDENTS IN RESIDENTIAL HIGH-RISE BUILDINGS IN TERM OF SUSTAINABILITY IN ERBIL CITY 2021-01-05T16:43:06+00:00 WEZHA HAWEZ BAIZ ERCAN HOSKARA <p>Land price, global icon, and rising population are among the obvious factors to encourage mega <br>structures in Erbil city. Consequently, high-rise and tall buildings have developed and spread in various <br>ways in the city and living in apartments is currently a lifestyle phenomenon. The main purpose of this <br>paper is to investigate the high-rise residential satisfaction. Through it, those factors have affected on the <br>satisfaction level of residences in residential high-rise buildings of a subset of subjects are analysed in the <br>elected two residential high-rise buildings in the city. The background, through literature review, focuses <br>on determinants sustainability that have an impact on residential satisfaction as the design of the units, <br>building material qualities, security and safety, confidentiality and privacy, socio-cultural aspects, and <br>community. In another word, this study focuses on the sustainable indicators in high-rise residential <br>buildings. The main method for understanding the perception of residents is questionnaires, which related <br>to the apartment, the building, and the surrounding area, with between 18 and 80 years of age in the sample <br>population. The findings demonstrated general significant factors of satisfaction in the high-rises as <br>architectural designs of apartments, space arrangement, and facilities.</p> 2021-01-05T16:43:06+00:00 Copyright (c) 2021 Journal of Duhok University EVALUATION OF EFFECT OF THE FLEXIBLE SHEAR CONNECTOR TYPE EMBEDDED IN HIGH AND NORMAL STRENGTH CONCRETE ON LOAD-SLIP RELATIONSHIP 2021-01-05T16:48:58+00:00 SHAHO MAHMOUD HAMA KHALIL I. AZIZ SHAMIL K. AHMED <p>Shear connectors resists shear force that developed between interface of concrete and steel and then<br>prevent pull – out failure. Stud shear connectors are commonly used and most of research focused on <br>behavior of this type. It's useful to study behavior and efficiency of other types. This investigation is about <br>the effect of different parameters on load-slip and stiffness of flexible shear connectors. Three <br>parameters were considered in this investigation; strength of concrete (35.5 and 62 MPa); type of <br>connector (stud, C-shape and L-shape) and type of connection between shear connectors and steel section. <br>It was found that increasing the compressive strength led to decrease in slip while load increasing. <br>Stiffness of connectors increased with increasing of compressive strength. The stud connectors found to be <br>stronger than C-shape and L-shape connectors while C-shape is the weakest one. Finally using welding <br>connection gave a higher load, lower slip and higher stiffness compared to epoxy regardless of type of <br>connectors and strength of concrete.</p> 2021-01-05T16:48:58+00:00 Copyright (c) 2021 Journal of Duhok University EFFECT OF DIFFERENT PARAMETERS OF THE BIOLOGICAL PROCESSES ON THE SPECIFIC GROWTH RATE OF NITRIFYING BACTERIA BY MEANS OF MATHEMATICAL MODELS 2021-01-05T16:55:48+00:00 KAROJ NAJMAN STEFAN PANGLISCH VICTOR KATAYAMA <p>In this study, the biological removal of nitrogen from wastewater with relatively high ammonium <br>concentration is investigated by modelling and simulation. Specifically, the nitrification process, means the <br>oxidation of ammonium to nitrate, which is catalysed by two types of bacteria, namely <br>ammonium-oxidising bacteria (AOB) and nitrite-oxidising bacteria (NOB). In wastewater treatment, <br>ammonia oxidation lowers the pH of wastewaters with in relation to total ammonia limited alkalinity. By <br>reducing the pH, ammonia oxidation often stops just below pH 6-6.5. On the other hand, nitrification has <br>been found to occur even at low pH in reactors that process human urine, although it was not clear which <br>species of bacteria are involved. Against this background, this research used different mathematical <br>models of ammonia-oxidising bacteria (AOB). The aim is to estimate those sludge residence times as a <br>function of pH that can achieve complete nitrification of the NH3-N load in the influent. Quantity of base <br>that should be dosed to the system and the capacity of the bioreactor have been calculated using estimated <br>data. The values obtained have also been compared with the values from literature.</p> 2021-01-05T16:55:47+00:00 Copyright (c) 2021 Journal of Duhok University COMPARATIVE ANALYSIS OF OPC BRANDS COMMONLY USED IN KURDISTAN REGION-IRAQ 2021-01-05T17:19:01+00:00 MUDHAFER H. SELMAN <p>Nowadays the brand of cement used in construction works is selected mostly on experience, <br>availability, and cost. This study aims to evaluate and compare the chemical and physical properties of <br>five brands of commercial ordinary Portland cement (OPC) available in the Kurdistan region, which are <br>(Mass, Delta, Kar, Mardin, and Şanliurfa). Several tests on each cement brand’s sample have been done in <br>the laboratory to analyze their properties according to British Standards (BS). The chemical composition <br>of the cement brands was analyzed by x-ray fluorescence method and the cement tests also include <br>(normal consistency, initial setting time, final setting time, soundness, loss of ignition, fineness, flexural <br>strength, and compressive strength). The effect of chemical composition on the mechanical properties also <br>studied. The results show that all samples have chemical contents within the acceptable limits. Şanliurfa <br>cement has the highest compressive strength at 28 days with 55.4 N/mm2<br>and it is about 27.7% more than <br>Kar cement, which has the lowest compressive strength of all tested cement brands. The MgO/SO3 ratio <br>results show that the Şanliurfa cement has the lowest ratio with 0.62 comparing with other cement brands<br>and this influences its compressive strength results. The (Mardin, Mass, Delta, and Kar) cement were <br>found to be classified as 42.5N class, these cement brands recommended to be used in bearing concrete <br>structural elements, commercial ready mix concrete plants, and rigid pavement construction work. On the <br>other hand, the study found that Şanliurfa cement classified as 52.5N class and it is recommended to use in high strength concrete <br>works.</p> 2021-01-05T17:19:01+00:00 Copyright (c) 2021 Journal of Duhok University BEACONDRIOD: AN AUTOMATED STUDENT ATTENDANCE SYSTEM 2021-01-05T17:26:46+00:00 AREE ALI BAMO NADIR <p>Until today, student attendance taking proves to have remained as one of the most challenging tasks in <br>educational organizations. Time efficiency, authenticity together with cost have been major influential <br>factors for many proposed systems in the past to tackle such a challenging task. Nevertheless, such <br>proposed systems lack one or more of these issues. This paper introduces an idea in which smartphones <br>owned by students and teachers are used as the main building blocks of an attendance system that <br>addresses these three major issues. The proposed system takes advantage of the built-in Bluetooth Low <br>Energy (known as BLE) of the smartphones such that it turns them into Beacon Transmitters and <br>Receivers. Two different applications are developed, one of which is installed on the student smartphones <br>turning into a Beacon Transmitter while the other is installed on the instructor’s device acting as a Beacon <br>scanner. Students are automatically marked as present, once s/he enters the classroom with the app <br>running. When the instructor is satisfied with the attendance, s/he can send the data to a remote server.</p> 2021-01-05T17:26:46+00:00 Copyright (c) 2021 Journal of Duhok University OPTIMIZING VIDEO TRANSMISSION PERFORMANCE IN 5GHZ MANET 2021-01-05T17:32:35+00:00 GHASSAN A. QASMARROGY <p>Nowadays, one of the most important technologies is video transmission. It is used worldwide across <br>multiple platforms such as mobile, tablets, smart watches, and many more. All these devices use the <br>2.4GHz and 5GHz frequency ranges of IEEE 802.11. Due to the mobility of these devices, it’s very <br>important to optimize video transmission streaming between these mobile devices with minimum delay <br>and higher throughput. In this paper, an attempt will be made to enhance the transmission performance <br>of video over MANET using IEEE 802.11n 5GHz frequency range supported by the new devices. The<br>performance of two famous routing protocols, AODV and OLSR, is compared in terms of delay, <br>throughput, and retransmission attempts.</p> 2021-01-05T17:32:35+00:00 Copyright (c) 2021 Journal of Duhok University STATE-OF-THE-ART REVIEW: CONCRETE MADE OF RECYCLED WASTE PET AS FINE AGGREGATE 2021-01-25T11:03:27+00:00 SHAKER MAHMOOD ABDAL QAIDI YAMAN SAMI SHAREEF AL-KAMAKI <p><br>It is well known that the foremost environmental sustainability concern derives from the abundance of <br>the plastic waste. The growing problem of the plastic waste originates from the presence of Polyethylene <br>terephthalate (PET) from plastic bottles. Nevertheless, the versatile performance of PET in terms of its <br>lightweight, strong, flexible, moisture-resistant, and cheap can make it a replacement substance for <br>aggregates in green concrete. On the other hand, PET replacement has mostly been restricted to <br>non-structural uses, generally due to its lower strength/stiffness, larger creep and shrinkage, poorer <br>durability associated to natural aggregate concrete (NAC). This paper presents a comprehensive review of <br>the published studies on waste recycled plastic by means of fine aggregate replacements. Parameters <br>including fresh concrete properties (workability and density) and the hardened concrete properties <br>(compressive strength and splitting strength) have been considered. After a detailed review it was found <br>that most of the studies conducted in the area of using PET as a fine replacement outlined the adherence <br>between concrete and PET.</p> 2021-01-05T00:00:00+00:00 Copyright (c) 2021 Journal of Duhok University DESIGN OF RECTANGULAR-SHAPED MICROSTRIP PATCH ANTENNAS FOR MILLIMETER WAVE BANDS 2021-01-05T18:01:23+00:00 RAWAZ HUSSAIN ABDULLAH KAWAN FAIQ AHMED <p>This study presents the design and simulation of two separate rectangular shaped microstrip patch <br>antennas to operate at 38 GHz and 50 GHz millimeter wave (mmWave) bands, using high-frequency <br>structure simulator (HFSS) software package. The work mainly underlines the importance of utilizing a <br>dialectic substrate from ROGRES Corporation. The substrate is used in the design of the proposed <br>antennas, and is made up of hydrocarbon ceramic laminates, known as the RO4350B. The influence of the <br>dielectric material has been studied on the performance of the antennas, like return loss, voltage standing <br>wave ratio (VSWR), antenna bandwidth, antenna gain, and radiation pattern. The obtained 38 GHz <br>antenna has about 8.06 dBi of gain and a 4.01 GHz of bandwidth with a return loss of less than -10dB <br>from 35.23 GHz to 39.24 GHz. On the other hand, the 50 GHz antenna provides a 5.1 dBi of gain with <br>much higher bandwidth (up to 7.2864 GHz) starting from 47.1106 GHz to 54.397 GHz. Beside these <br>remarkable features, the thickness of the selected substrate is 0.762 mm. Both antennas might be used in <br>future 5G wireless communication systems and short-range systems such as machine-to-machine (M2M) <br>and device-to-device (D2D) to fulfill the necessities of wide-bandwidth, high-gain, low-weight, cheap, and <br>easy fabrication.</p> 2021-01-05T18:01:23+00:00 Copyright (c) 2021 Journal of Duhok University THE AUTOMATIC LICENSE PLATE RECOGNITION USING FEATURES EXTRACTION AND NEURAL NETWORKS 2021-01-05T18:07:31+00:00 REEM Q. ABDULJABBER MOHAMMED A. SHAKIR <p>The automatic license plate recognition (ALPR) system opens the trendy door to the researchers to <br>think, discover techniques and reach to a result for its necessity. The important of the ALPR system is <br>appeared in the transportation for many reasons such as parking, traffic violations and security. The aim <br>of this paper is to suggest a scheme that will extract car number, country and province from the car <br>images. The proposed scheme is based on digital image processing techniques and neural networks. The <br>proposed algorithm is composite of preprocessing and recognition stages. The preprocessing stage includes: <br>locate the car plate region, binarization, enhancement of the image quality, segment the image into the <br>sub-images. The recognition stage will classify and recognize the segmented sub-images as numbers and <br>characters. In this research, the localization is done through normal cross correlation method. The <br>segmentation includes: segment the car plate into three regions, divide the number and separated <br>character into individual and split the connected characters into separated characters are done through <br>suggested algorithms. The recognition is accomplished using the back propagation neural network<br>(BPNN). The recognizer operates on two sets of data. First set of data includes the whole pixels of the <br>sub-images. The second set of data is based on 16 features extracted from the sub-images. A comparison <br>between these two methods is made. The system is experienced on 99 images of Duhok and Erbil provinces, <br>the environment work is done with MATLAB program. The percentage accuracy is: 100%,100% and 100% <br>for the localization, distinguish and segmentation respectively. The recognition rate result for the first <br>method is 94.5% and the second method is 91%.</p> 2021-01-05T18:07:31+00:00 Copyright (c) 2021 Journal of Duhok University THE EFFECT OF FREEZE-THAW CYCLES ON THE GEOTECHNICAL PROPERTIES OF CLAYEY SOIL TREATED WITH LIME 2021-01-05T18:53:08+00:00 NIHAD BAHAALDEEN SALIH TAVGA ARAM ABDALLA <p>Fine-grained soils (cohesive soils) exposed to freezing-thawing cycles exhibit to notable alterations on<br>their physical and mechanical characteristics. The environmental conditions' influences on soil <br>geotechnical properties are significant, especially when stabilized by hydrated lime. This study was <br>carried out to explore the effect of freeze-thaw cycles on cohesive soil stabilized by various hydrated lime <br>percentages (zero%, 5%, 10%, and 15%) by dry mass, which cured for 28 days at 30°C. One-dimensional <br>consolidations, unconfined strength, and shear box tests were performed for untreated and treated soil <br>samples subjected to 0, 1, 2, and 3 freeze-thaw cycles. Duplication of freeze-thaw cycles significantly <br>impacts some geotechnical properties and decreases them such as LL, UCS, Cc, Cr, and C. The PL and ϕ<br>values of the samples treated by hydrated lime and subjected to freeze-thaw cycles observed to be <br>increased, which were due to the important role of hydrated lime addition. It is concluded that the <br>hydrated lime can be effectively utilized to minimize the impacts of freeze-thaw periods on shear strength <br>and compressibility of cohesive soil.</p> 2021-01-05T18:53:08+00:00 Copyright (c) 2021 Journal of Duhok University LANE CHANGING CHARACTERISTICS FOR DIFFERENT TYPES OF ROADS IN NAJAF 2021-01-05T19:01:12+00:00 HAMID A. AL-JAMEEL ALI JIHAD KADHAM <p>Investigating a driver behavior under different traffic conditions is the main point to develop a<br>microscopic traffic model such as the Frequency of Lane Changing (FLC) and Lane Utilization (LU). The <br>LC model is the corner stone for developing each traffic software; especially traffic simulation models. <br>The main aim of this study is to investigate the FLC and LU under different traffic conditions such as <br>urban and rural roads. Furthermore, the FLC for each type of road two-or three-lane sections has been <br>investigated. Field data have mainly been collected from urban arterial roads; whereas other published <br>data have been used for this study. High FLC has been observed in Iraqi roads comparing with other <br>countries. This behavior could be attributed to the aggressive behavior and the absence of pavement <br>parking.</p> 2021-01-05T19:01:11+00:00 Copyright (c) 2021 Journal of Duhok University ALL-OPTICAL NETWORKS PERFORMANCE IMPROVEMENT BY SOLVING THE RWA PROBLEM USING GENETIC ALGORITHM 2021-01-05T19:06:52+00:00 MOHAMMED GHANIM SAEED FIRAS MAHMOOD MUSTAFA <p>The problem of significant importance in the design of all-optical networks is the Routing and <br>Wavelength Assignment (RWA) problem that depends on the light path route and wavelength using <br>different algorithms. The main aim of (RWA) is to maximize the number of established connections. The <br>significant indication by applying the RWA is to diminish the resources of the network demanded to serve <br>the same number of requests. Consequently, the total number of requests served by the same resources <br>will be increased. The main aim of this research is to manage the RWA algorithm by inspecting the <br>performance of each algorithm in static (Fixed Routing Algorithm and Fixed Alternate Routing Algorithm) <br>and dynamic routing algorithms in an optical network. With this work, the comparison between various <br>RWA algorithms is performed using sorted shortest path algorithm and non-sorted random algorithm. <br>Extra investigation and comparison can be achieved via the hiring Genetic algorithm (GA) as a tool to <br>enhance optical network performance. The proposed techniques are applied to the design of some <br>topologies depending on the number of nodes and the set of connecting links. With this work, it is assumed <br>that all nodes are with no wavelength conversion and the identical load was utilized on the network by <br>using three different algorithms. The comparison between the three algorithms shows that the dynamic <br>algorithm gives good throughput and less resource usage. Besides, it has been shown that the shortest path <br>algorithm yields results better than a random path algorithm. Finally, by using the GA tool in the <br>optimization, the results have been obtained within the accepted rate.</p> 2021-01-05T19:06:51+00:00 Copyright (c) 2021 Journal of Duhok University EXPERIMENTAL VERIFICATION AND REVIEW PERFORMANCE OF THE MODIFIED TRIANGULAR PLAN FORM WEIR 2021-01-06T17:27:52+00:00 SHAKER A. JALIL RONDIK A. JAFAR SAFA S. IBRAHIM <p>Weirs are discharge measurement structures have different geometrical shapes. The performances of <br>the modified triangular plan form weirs were studied under free-flow condition. Three groups of weirs <br>were tested experimentally. The first group has a flat top; the second has one slope and the third has two <br>slopes. Each group has three vertex angles (60o<br>, 90o<br>and 120o<br>) with constant height. The hydraulic<br>performances of weirs are based on the ability to pass the discharge for certain head flow and on the value <br>of the coefficient of discharge. The values of discharge and the coefficient were compared with earlier <br>studies being carried on conventional normal weir, broad crest, triangular plan-form and different <br>labyrinth weirs. All the groups show better performance than conventional shaped and broad weir. The <br>magnification of the actual discharge to the discharge of broad crested weir is more than one and the best <br>one is the first in the third group, while the vertex angle is (60o<br>) for the second and third group and (120o<br>)<br>for the first. The performance of the third group is better than rectangular labyrinth weirs, and it is <br>compatible with the triangular labyrinth. The discharge coefficient decreases with the increase of relative <br>value of the head to the height of weir except for the first group. Equations for predicting coefficient of <br>discharge are proposed within the limitations of this test.</p> 2021-01-06T17:27:52+00:00 Copyright (c) 2021 Journal of Duhok University TREND ANALYSIS USING MANN-KENDALL AND SEN’S SLOPE ESTIMATOR TEST FOR ANNUAL AND MONTHLY RAINFALL FOR SINJAR DISTRICT, IRAQ 2021-01-06T17:42:40+00:00 FAWAZ KH. ASWAD ALI A. YOUSIF SAYRAN A. IBRAHIM <p>The time series rainfall data of 70 years (1940 – 2010) of Sinjar District used to identify the trend and <br>slope magnitude of this series. To analyze the trend, the non-parametric test (Mann-Kendall test) and<br>Sen’s slope estimator were used. For developing a functional relationship between variables, a linear trend <br>of rainfall data for the studied area evaluated using the linear regression. The annual trend analysis <br>showed decreasing trend because the value of Mann- Kendall’s tau and the magnitude of Sen’s slope <br>estimator were both negative and was found to be - 0.06501 and -0.7283, respectively. Also for the slope of <br>the linear regression was negative and equal to −0.916 mm/year, which represents the rate of decreasing in <br>trend for yearly annual rainfall. In addition, the results showed that the trend analysis of monthly rainfall <br>has a varied trend of rainfall in the rainy months. Finally, the results showed a positive trend (increasing) <br>for the months of October and April and negative trend (decreasing) for the other months.</p> 2021-01-06T17:42:40+00:00 Copyright (c) 2021 Journal of Duhok University EXPERIMENTAL INVESTIGATION OF SOME MECHANICAL PROPERTIES OF RUBBERIZED CONCRETE WITH HIGHEST POSSIBLE RUBBER CONTENT 2021-01-06T17:49:26+00:00 WRYA A. ABDULLAH MUHAMMAD A. MUHAMMAD MOHAMED R. ABDULKADIR <p>Each year more than a billion tires are discarded globally, millions of them are disposed to landfills <br>especially in the developing countries which leads to serious environmental issues. This paper<br>experimentally investigates mechanical properties of concrete containing highest possible ratio of recycled<br>tire rubber content as fine aggregate replacement in terms of compressive strength, workability, dry and <br>fresh densities. For this purpose, eleven different concrete mixes were cast with various sand replacement <br>ratios by mass from 0% to 60% with increments of 6%. Three cubic specimens from each mix were cast <br>and tested to measure the mechanical properties at the age of 28 days. All the specimens had the<br>water-cement ratio and curing period without using any admixtures. It is concluded that the workability, <br>density, and compressive strength of the rubberized concrete samples are significantly reduced with an <br>increase of the rubber content. Moreover, it is observed that the mix becomes stiff and non-workable <br>beyond 60% of rubber content. Furthermore, the test results are compared with non-rubberized concrete <br>(control mix) and the available data on rubberized concrete from the literature. Finally, equations for <br>predicting the aforementioned properties are derived.</p> 2021-01-06T17:49:25+00:00 Copyright (c) 2021 Journal of Duhok University DEFORMABILITY AND SHEAR STRENGTH PARAMETERS OF THE FOUNDATION OF A PROJECT ON TANJERO FORMATION IN IRAQ USING RMR AND GSI 2021-01-06T17:53:27+00:00 YOUNIS M. ALI ALSHKANE <p>Determination of the shear strength and deformability parameters of weak rocks are very significant <br>in order to design the foundation of buildings on it economically and safely. Tanjero formation consists of <br>an alternation of sandstone and silty marlstone and it is considered as a weak rock layer which makes it <br>difficult to determine precisely its bearing capacity. Understanding the behavior of this formation under <br>loading is one of the most challenges in geotechnical engineering. The formation underlies most of the <br>areas in Sulaimani city and significant projects such as Shari Daik and Barzayakni Sulaimni projects in <br>Sulaimani city in Iraq. In this paper, the mentioned parameters of this formation were predicted and <br>recommended for the foundation of a multi-story building at Shari Daik project in Sulaimani city in Iraq <br>based on Rock Mass Rating (RMR) and Geological Strength Index (GSI) rock systems.</p> 2021-01-06T17:53:27+00:00 Copyright (c) 2021 Journal of Duhok University EXPERIMENTAL DETERMINATION OF STATIC AND DYNAMIC ELASTIC MODULI OF RC SLABS 2021-01-06T19:01:54+00:00 MEZGEEN S. AHMED ABDULHAMEED A. YASEEN YAMAN S. S. AL-Kamaki FOUAD A. MOHAMMAD <p>The purpose of this paper is to experimentally determine the static (Ec) and dynamic (Ed) elastic <br>moduli of reinforced concrete (RC) from both static and dynamic techniques. Initially, the <br>aforementioned parameters were estimated from the concrete compressive strength of the used mix, using <br>compressive strength machine. Subsequently, the RC slab specimens themselves were dynamically tested <br>dynamically under free boundary conditions. Then from, the experimentally measured natural frequency, <br>the static and dynamic moduli were determined. To check the reliability of the dynamic test for estimating <br>the natural frequency, the intact and defected slabs were utilized. The dynamic test was performed on four <br>RC square slab samples of dimensions 600 mm × 600 mm × 40 mm. The first set, two intact slabs, is used <br>as control specimens were prepared with no artificial voids. While, the second set, two defected slabs, is <br>used as defected specimens. The defected slabs contained the artificial void by fixing a polystyrene block <br>at the center of the steel reinforcement of the slabs prior to pouring concrete. In the latter technique, a RC <br>slab specimen is hanged by using elastic ropes to approach fully free boundary conditions. The slabs were <br>excited by an impact hammer, to induce vibration, whilst the accelerometers were employed to record the <br>response under such excitation. Pico Scope 6 device and amplifier was used to acquire, magnify and <br>analyze the data. In addition, MATLAB software is used to convert the time domain to the frequency <br>domain as well as to plot Frequency Response Function (FRF). The first natural frequency is determined <br>as the first resonant peak on the FRF plot. It is showed that the use of the first natural frequency-based <br>method can be usefully employed to determine the dynamic modulus of elasticity of concrete. It was found <br>that the testing sequence did not significantly affect the measured results for the obtained Ec and Ed in <br>this study&nbsp;</p> 2021-01-06T19:01:54+00:00 Copyright (c) 2021 Journal of Duhok University GROUNDWATER CHARACTERISTICS ASSESSMENT IN KURDISTAN REGION PROVINCES-IRAQ: A REVIEW 2021-01-06T19:17:24+00:00 DARA MUHAMMAD HAWEZ NASHWAN SHAWKAT MIZZOURI SHUOKR QARANI AZIZ JWAN SABAH MUSTAFA SHWANA BRAIM HASSAN MANGURI <p>Over the past decades, drilling wells and groundwater extraction for agricultural, domestic, and <br>industrial purposes is growing at a high rate in Kurdistan Region-Iraq, meaning that groundwater <br>becomes one primary water source. Increased demand for water and over-exploitation and unsustainable <br>practices severely deteriorate groundwater. Therefore, it is essential to monitor the water quality. In the <br>past years, many papers have been published on groundwater quality in the Kurdistan Region. Thus, this <br>research aims to review, evaluates and summarizes the results of published papers concerning <br>groundwater characteristics in Erbil, Suliamni, Duhok, and Halabja, Governorates. This work targets <br>about thirty published papers. These papers focused on Wells, Springs, and karizes (qanats) as <br>groundwater. The water testes have taken from different cities and locations in these three governorates. <br>The reviewed studies considered a number of water parameters and chemical elements, such as <br>physicochemical parameters, heavy metals, and radioactive substances. This work assesses water quality <br>parameters from reviewed studies and illustrates the comment parameters by the spatial distribution <br>mapped using the kriging method. Generally, the groundwater polluted in some zones in the Kurdistan <br>Region and normally it can be used for drinking and domestic uses after the disinfection process.</p> 2021-01-06T19:17:24+00:00 Copyright (c) 2021 Journal of Duhok University EMPIRICAL PARKING STUDY IN UNIVERSITY OF DUHOK CAMPUS 2021-01-11T10:58:03+00:00 NAHLA HUSSEIN ASWAD <p>University of Duhok campus in Duhok city, Kurdistan region, Iraq, suffers from a serious mobility <br>problems and illegal on-street parked cars resulting from continuous development of campus without<br>proper policy and program to control the problem. The aim of this paper is to present empirical parking <br>study in University of Duhok (UoD) campus by assessing and examining the present supply of parking. <br>Besides, it aims to find the maximum expected number of parking spaces that would be able to <br>accommodate the current parked vehicles, and the expected number of parking spaces to accommodate<br>the future demand of spaces. Several related parking surveys were conducted in the university campus, <br>involved: current parking supply, computing the available off street parking capacity, license plate survey <br>and questionnaire survey for campus parkers. The UoD main campus inventory results indicated that <br>there are 2,027 available spaces which distribute on 27 lots. Campus parkers’ behavior has been evaluated <br>from quantitative samples (more than 600) of parkers. Data was collected laterally nine hours by <br>observing and recording the vehicles license plate number to study vehicles parking duration. It was <br>observed that a massive number of vehicles were parked with short parking duration and the maximum <br>parking index was appeared from 10:30 a.m. to 11:00 a.m. With the continuous progress in campus <br>population and land uses development for different purposes, the UoD main campus suffers from <br>insufficient supply spaces for parkers. In addition to that, it is estimated that the parking spaces demand <br>will remain to growth in the forthcoming years due to the campus circumstance.</p> 2021-01-06T00:00:00+00:00 Copyright (c) 2021 Journal of Duhok University EXPERIMENTAL STUDY OF LIGHTWEIGHT REINFORCED CONCRETE HOLLOW ONE-WAY SLABS WITH PARTIALLY REPLACEMENT BY RECYCLED COARSE AGGREGATE 2021-01-06T19:59:16+00:00 BARAA T. KAMEL MUYASSER M. Jomaa'h HOSAM A. ALAZZAWI <p>The technological development, together with the society tendency to replacing old methods through <br>the applications of the construction materials with high efficiency, low costs and high durability by using <br>structural thermal insulation systems, intends to increase the design age of the facilities and reduce energy <br>consumption. Therefore, the study of light weight hollow concrete panels, becomes an important scientific <br>goal in structural engineering. This study aimed to use lightweight and recycled materials as coarse <br>aggregates to produce environmentally friendly concrete. Thirty-nine specimens of hollow one-way <br>reinforced panels with dimensions (800 x 400 x 100) mm have been prepared and classified into four <br>groups (3 panels used as reference specimens and 9 panels per each group). Claystone (ponza),<br>thermostone aggregates, waste rubber pieces from used tires and polystyrene (cork) with volumetric <br>replacement ratios of (25, 50 and 75) percentages of the normal aggregate were used respectively. The <br>mechanical properties of the concrete mixtures were studied by preparing (60) samples of cylinders and <br>prisms. The test results indicated a decrease in the mechanical properties with an increase in the <br>percentage of lightweight coarse aggregate (25, 50 and 75 percentages). Compressive strength, tensile <br>strength, flexural resistance and the density of the concrete test results were (10.66 – 38.44) MPa, (1.122 –<br>3.969) MPa, (3.606 – 10.467) MPa and (1665.5- 2426.41) kg / m3<br>respectively, while the ductility index in <br>the range of (1.61-3.33). The results showed that using lightweight aggregate contributed in reducing the <br>dead load of the proposed specimens, in addition, the best concrete mixture was that replaced by 75% of <br>the normal aggregate with thermostone and rubber materials, as it achieved low density and acceptable <br>compressive strength (1755.8 kg / m3<br>, 15.47 MPa) and (1835.5 kg / m3<br>, 15.47 MPa) respectively. The <br>internal voids ratio of the sample was adopted with a total ratio of 20% of the total size of the standard <br>sample. The results of the bending moment capacity test of the hollow panels for failure load values <br>ranged between (23.704 – 9.259) kN for the adopted group specimens compared with the reference <br>specimen which achieved a maximum failure load of (24.810) kN.</p> 2021-01-06T19:59:16+00:00 Copyright (c) 2021 Journal of Duhok University PROBABILISTIC SETTLEMENT ANALYSIS OF STRIP FOOTING ON SPATIALLY RANDOM SOIL 2021-01-24T18:52:03+00:00 RIZGAR H. AHMED MOHAMMED S. HUSSAIN <p>The prediction of settlement in a traditional design approach usually uses a deterministic value of <br>modulus of elasticity (E), which is estimated as an average value by testing the soil at selected locations. <br>However, these deterministic properties of soil may not represent the actual properties of soil and site <br>condition. Due to numerous sources of uncertainty, the properties of soil mass are spatially varying and <br>anisotropic in the natural field condition. In this study, a random finite element method (RFEM) is used to <br>evaluate the reliability of settlement of the strip footing on spatially random soil. Modulus of elasticity is <br>the only considered random parameter. For this purpose, 2000 spatially random realizations of E-field are <br>generated using Monte Carlo Simulation. Each of these realizations of heterogeneous soil profile is passed <br>to FEM to analyze the settlement of footing. The final settlement results measured in all these realizations <br>are then statistically evaluated and compared. The results of analysis show that the mean and standard <br>deviation of the footing settlement are increased with increasing spatial correlation length. The large value <br>of isotropic correlation length led to an increase in the mean settlement value by more than 25% as <br>compared with the deterministic settlement calculations. Also, it is concluded that the rate of increase of <br>settlements for anisotropic correlation length is lower than the one under isotropic condition.</p> 2021-01-06T00:00:00+00:00 Copyright (c) 2021 Journal of Duhok University INVESTIGATION OF FLEXURAL PERFORMANCE OF CONCRETE BEAMS REINFORCED WITH GLASS FIBER REINFORCED POLYMER REBARS 2021-01-06T20:39:32+00:00 MUHAMMAD A. MUHAMMAD FARIS R. AHMED SERWAN KH. RAFIQ <p>As a solution of steel corrosion, glass fiber reinforced polymer (GFRP) rebars have been recommended <br>to be used as internal reinforcement instead of steel reinforcement during last two decades. Lightweight, <br>no-corrosion, thermal conductivity, electrically and magnetically resistance, and higher tensile strength <br>are main advantageous properties of GFRP rebars over steel reinforcement. However, it has been noted <br>that the recommended design codes in this field still require modifications. Some studies were conducted <br>on concrete structures reinforced with this new reinforcing material worldwide. In this paper, test data of <br>fifty-three concrete beams reinforced with GFRP rebars were collected from eight different works to <br>investigate cracking moment, nominal moment, deflection and neutral axis depth. The selected beams <br>were reinforced with steel stirrups and GFRP rebars in traverse and longitudinal directions, respectively. <br>The beams were tested under four-points loading test to fail in flexure. A comprehensive approach to <br>calculate both experimental and predicted results is given in terms of deflection and flexural capacity. The <br>experimental results are compared with calculated design results according to ACI 440.1R-15. Statistical <br>data analysis is performed for both theoretical and experimental results. In conclusion, the multiplier <br>factors for theoretical cracking moment, nominal moment, ultimate deflection and neutral axis depth have <br>been proposed to be 0.94, 1.25, 1.4 and 0.806, respectively.</p> 2021-01-06T20:39:32+00:00 Copyright (c) 2021 Journal of Duhok University MIX PROPORTIONING OF SELF COMPACTING CONCRETE USING LIMESTONE POWDER 2021-01-06T20:45:25+00:00 AVRAZ ZAINALDEEN GHANIM HUSSEIN QOJA <p>Self-compacting concrete (SCC) is a kind of concrete mixtures that can be used for placing in <br>congested reinforcement structures without external vibrations. SCC has improved qualities and enhances<br>concrete durability, working conditions, and productivity. This paper proposes an experimental <br>procedure for the mix proportioning of SCC, considering M30 and M60 Grade concrete strength. Using <br>limestone powder as a filler based on the aggregate packing principle and EFNRAC guideline for mix <br>design. The tests that represent the properties of SCC in the plastic stage such as; V-funnel, slump flow,<br>T500, L-Box, J-ring, and Sieve Segregation resistance were carried out. While in the hardened stage, the <br>compressive strength was obtained at the ages of 7, 14, 28, and 56 days. The test results show that using 88 <br>kg of limestone powder per unit volume can produce successfully SCC with compressive strength of 74.3 <br>MPa at 56 days while using 225 kg of limestone powder produce SCC of compressive strength of 36.7 MPa <br>at 56 days</p> 2021-01-06T20:45:25+00:00 Copyright (c) 2021 Journal of Duhok University EFFECT OF SAWDUST AS PARTIAL REPLACEMENT OF SAND IN CONCRETE 2021-01-06T20:53:51+00:00 DABAN A. MUHEDIN SANGAR J. QADIR MADEH I. HAMAKAREEM AHMED J. HAMA RASH <p>In the past, river sand was main choice for fine aggregate but due to nonscientific methods for <br>excavation from river beds it has been depleted and leads to environmental concern. Most of the waste <br>sawdust are being dumped into landfill areas which is undesirable because it has a negative impact on <br>environment. This research investigated the effects of sawdust as partial replacement for fine aggregate in <br>concrete structures. Compressive, tensile and flexural strength were investigated and evaluated at 7, 14 <br>and 28 days. In this study four concrete mixes were prepared, first one was control mix and in other three <br>mixes sand was replaced by the following percentages 5%, 10% and 15%. Results shows that by <br>increasing the amount of sawdust in concrete samples; compressive, tensile and flexural strength will <br>reduce. Compressive strength for 5% of sawdust replacement at 28 days was 26.2 MPa, while for 10% was <br>20.1 MPa and for 15% was 15.9 MPa. The test results, indicated that 5% of sawdust can be used in <br>concrete structures.</p> 2021-01-06T20:53:51+00:00 Copyright (c) 2021 Journal of Duhok University SOLVING RWA PROBLEM IN ALL-OPTICAL NETWORKS BASED ON OPTIMIZED ANT COLONY ALGORITHM 2021-01-07T17:01:00+00:00 MAYSAA ALI ABDULLAH FIRAS MAHMOOD MUSTAFA <p>The information bandwidth growth can be achieved using optical networking technology. Optical fiber <br>has been used as a physical means through many network technologies. Wavelength Division Multiplexing <br>(WDM) has emerged as a promising technology to conquer the use of large-bandwidth in optical networks. <br>In WDM network, the essential problem is to serve the load traffic represented by the requests that arrive <br>at the network and need to be served. For serve the request, the network will determine a path paired with <br>a specific wavelength used to send the request's data from source to the destination node. This problem is <br>called the routing and wavelength assignment (RWA). In this work, Multi-Node Optimized Ant Colony <br>Algorithm (M-NOACA) proposed and implemented to solve the RWA problem in all-optical networks by <br>simulating traffic with the RWA algorithms. A performance measurements applied to study the <br>optimization problem of the RWA, and apply a comparison with the classic algorithms. Determining the <br>best collection of parameters for an ant-based algorithm to obtain the best performance remains an open <br>issue, in this work, a study is done to introduce a new contribution to obtain the optimal setting of Ant <br>Colony parameters used to solve the RWA problem.</p> 2021-01-07T00:00:00+00:00 Copyright (c) 2021 Journal of Duhok University THE DETERMINATION OF THE STRESS INTENSITY FACTORS OF A STEEL PLATE WITH DIFFERENT THICKNESS USING FEM 2021-01-07T17:07:26+00:00 YOUNIS KHALID KHDIR <p>This paper presents the finite element method for determining the stress intensity factors of steel plates<br>with different thickness having an elliptical cut-out in the center and subjected to different stresses. The <br>failure of the cracked parts affected by the stresses in the crack tip vicinity. The stress contribution can be <br>determined by the stress intensity factor K. For this purpose, an initial crack can be simulated and <br>modeled. Each of K corresponds to a crack propagation method. In this study the ANSYS software is used <br>for numerical modeling with several elements of solid type and nodes. a finer mesh is used around the <br>crack tip for more accurate results. Then an error percentage can be determined by using ANSYS results. <br>The present research is aimed to improve the formulation by including the effect of the crack-face closure <br>on the stress intensity factors K.</p> 2021-01-07T17:07:26+00:00 Copyright (c) 2021 Journal of Duhok University DESIGN, AND MANUFACTURING A SMALL-SCALE WIND TUNNEL FOR HEAT TRANSFER ANALYSIS OF FLAT PLATE AND FINNED PLATE HEAT SINKS 2021-01-24T18:56:29+00:00 ARKAN F. SAEED ODAY A. ABBO <p>Application that utilize heat sinks for cooling electrical devices have been increased significantly <br>during the last decade. In present work, the design and installation of small-scale wind tunnel have been <br>executed. An experimental analysis of flow over a flat plat combined with constant heat flux have been <br>investigated to ensure the effectiveness of the device. The design satisfied the basic equations of fluid flow <br>to get the required laminar flow before the test section. The calculations depend on the change in heat flux <br>across the flat plate and obtained results are compared with the previous published results for validation.<br>Experimental analysis of constant heat flux from a horizontal rectangular fin array (HRFA) under <br>controlled forced convection heat loss. The characteristics are investigated for fin with L / H = 1.416; the <br>effect of various parameters such as heater input with different fluid flow velocity on average heat <br>transfer coefficient (h) have been studied. The dimensionless number analysis like Nusselt number (Nu), <br>Reynolds number (Re), were investigated. The heat transfer from surface may, generally, be enhanced by <br>increasing the coefficient of heat transfer between a surface and its surrounding, or by increasing the area <br>of heat transfer surface. An empirical correlations have been differentiated relating Nusselt and Reynolds <br>numbers for both flat plate heat sink with the range 9.3x103<br> Re  19.1x103<br>, and Pr &lt; 1.0 with a total <br>error 5%, and finned plate heat sink with the range 7x103<br> Re  22.5x103<br>, and Pr &lt; 1.0 with a total error <br>6.4%.</p> 2021-01-07T00:00:00+00:00 Copyright (c) 2021 Journal of Duhok University CAPACITY IMPROVEMENTS BASED ON DYNAMIC SIGNAL TIMING AT SIGNALIZED ROAD INTERSECTIONS USING GENETIC ALGORITHM 2021-01-07T17:53:19+00:00 NAZA KHEDER GHANI BOTAN MAJEED AL- HADAD <p>Due to lack of public transportation, economic growth and the rapid increase in the number of <br>populations, the number of vehicles in Erbil city has recently increased dramatically. This increment <br>caused congestion on the roads and posed most of the loads on the traffic intersections, which already <br>have limited capacity. As the intersection volume increases, the degree of saturation (X) and delay <br>increases and, as a consequence, the Level-of Service (LOS) decreases, leading to instability and platoon <br>formation at the intersection approaches. One of the reasons of congestion at intersections is due to the <br>fixed signal timing during the day, while the traffic volume at the intersections varies from one hour to <br>another. This research suggests solutions to vehicle delays at intersections through using a Genetic <br>Algorithm (GA) based optimization model to adjust the signal parameters to fit the real time traffic <br>condition. The suggested model tries to optimize the cycle length besides the green time per phase for <br>different time lags throughout the day. The results showed distinct and remarkable improvements in the <br>intersection capacity with 2 to 13 % along with an average delay of 28- 64 %.</p> 2021-01-07T17:53:19+00:00 Copyright (c) 2021 Journal of Duhok University BEHAVIOR OF SQUARE REINFORCED CONCRETE COLUMNS STRENGTHENED BY DIFFERENT LAYERS OF GLASS FRP SHEETS 2021-01-07T18:20:52+00:00 MUHSIN KHALID KHDIR BAHMAN OMAR TAHA AHMED REDHA ABDULRAHMAN <p>The behavior of reinforced square concrete columns strengthened by specific layers of glass fiber <br>reinforced polymer (FRP) sheets were investigated through an experiment by testing of thirteen variety of <br>concrete columns that were axially loaded at their ends. The most variable thought of during this study <br>were the quantity or number of layers of glass fiber reinforcement polymer sheets and also the effect of <br>confinement techniques (fully wrapped, strip ties and spiral sheets). The test values were compared with <br>the proposed equation of ACI 440.2R-02, for samples strengthened by one layer of GFRP sheet can <br>upgrade the load carrying capacity of columns in numerous ways of strengthening (fully wrapped, strip <br>ties and spirally) by 25.5%, 6.7% and 29.5% respectively compared to the control (unstrengthen) column. <br>Be that as a result of it would, for columns strengthen by 2 layers of GFRP sheets (fully wrapped, strip ties <br>and spirally) the load carrying capacity increases by 36.5%, 19.6% and 29.8% respectively. While, for 3 <br>layers of strengthen sample the percent of enhancement in the load carrying capacity increases by 38.2%, <br>20.1% and 30.7% respectively. Finally, the load carrying capacity increases by 43.2%, 29.2% and 33.2% <br>for different confinement techniques (fully wrapped, strip ties and spiral sheets) respectively if they are <br>strengthened by 4 layers of GFRP sheets.</p> 2021-01-07T18:20:52+00:00 Copyright (c) 2021 Journal of Duhok University A THINNING-BASED JUNCTION DETECTION AND RESOLUTION ALGORITHM FOR DOCUMENT IMAGES 2021-01-07T18:29:13+00:00 HASAN S.M. AL- KHAFFAF ABDULLAH Z. TALIB <p>Junction detection plays a significant role in document image recognition. High recognition rate of <br>graphical primitives is correlated with the proper detection of junctions. In this paper, a junction detection <br>algorithm is presented in thinning-based raster to vector conversion process. The method has three stages <br>that leverage junction representation from pixels to features (i.e. junctions). The input image is thinned to <br>its skeleton. Edges were found next and pixels with many neighbours are designated as a low level <br>junction. Polygonal approximation on edges is used to detect L-junctions while connected component <br>analysis is used to find intermediate junctions. Intermediate junctions with a distance less than a threshold <br>are combined to form a high level X- and Y-junctions. Performance evaluation on mechanical engineering <br>drawings shows precision rate of 82.38% and a recall rate of 97.29%.</p> 2021-01-07T00:00:00+00:00 Copyright (c) 2021 Journal of Duhok University STUDY OF IN-SITU AND LABORATORY HYDRAULIC CONDUCTIVITY OF CONTAMINATED SOIL WITH OILY WASTEWATER 2021-01-07T18:37:13+00:00 FERZAND KAMAL AHMED MEDHAT YOUSIF ISMAEL MAWLOOD <p>This study aims to investigate the effect of contaminated soil samples with oily wastewater which were <br>taken from Kawergosk refinery (20 km west of Erbil city). Laboratory constant head permeability tests on <br>contaminated soil samples with oily wastewater have been conducted. Also, One-Dimensional (1-D) and <br>Three-Dimensional (3-D) in-situ permeability tests were performed. A noticeable decrease in the values of <br>hydraulic conductivity coefficient (k) have been observed for Contaminated Soil Samples comparing with <br>uncontaminated samples. Results of hydraulic conductivity coefficient obtained from one dimensional <br>consolidation tests were increased with increasing of applied stresses. The results of field permeability <br>tests revealed that the surrounding lands of Kawergosk refinery lies within the range of semi-permeable <br>area for urban development while the majority part of the area lies within the range of moderate area for <br>agricultural and conservation purposes.</p> 2021-01-07T18:37:13+00:00 Copyright (c) 2021 Journal of Duhok University