Tikrit Journal of Engineering Sciences

Urban extraction mapping has become increasingly important in recent years and particularity extraction urban features based on remotely sensed data such as high-resolution imagery and LiDAR data. Though the researchers used the high spatial resolution image to extract urban area but he methods are still complex
and still there are challenges associated with combining data that were acquired over differing time periods using inconsistent standards. So, this study will focus on the extraction of urban area based on an object-based classification method with integration of Quickbird satellite image and digital surface elevation (DSM) extracted from LiDAR data for the Rusafa city of Baghdad, Iraq. All the processes were done in eCognition and ArcGIS software for feature extraction and mapping, respectively. The overall methodological steps proposed in this research for the extraction of urban area using object-based method. In addition of that both the image data and LiDAR-derived DSM were integrated based on the eCognition software for extraction urban map of Rusafa city, Baghdad. Finally, the results indicated that the Artificial Neural Networks (ANN) model achieved the highest training and testing accuracies and performed the best compared to RF and Support Vector Machines (SVM) methods. And also, the results showed that the Artificial Neural Networks (ANN) had capability to extract the boundaries of the buildings and other urban features more accurately than the other two methods. This could be interpreted as the Artificial Neural Networks (ANN) model can learn complex features by the optimization process of the model and its multi-level feature extraction property.

Voltage unbalance is an adverse global phenomenon impacting three-phase induction motor output. Three-phase source voltage may become imbalanced in a variety of respects, while a balanced system preserves stable voltage magnitude and angles in three phases, but a completely balanced state is difficult to get. Imbalanced cases may differ in multiple ranges which may practically affect the motor. So, this work is an effort to analyze the operations with appropriate propositions. The output of a three-phase induction motor working with an imbalanced supply grid, MATLAB/SIMULINK is further used for simulation purposes and programming based on the asymmetrical component approach is adopted. A new design for system rerating is being proposed. As a case study, a 10 HP three-phase induction motor was used. The findings of the study show that to determine the output of the induction motor, positive voltage series must be respected under the voltage unbalance factor (VUF) or proportion voltage unbalance index with six various voltage magnitude imbalance conditions, the copper losses of three-phase induction motors were calculated under full load conditions by simulation. So, the qualified percentage change in total copper losses for the motor operating under imbalanced and balanced voltages was determined.

Color has a crucial impact on students’ perception. It encourages the learning atmosphere to be affiliated with the anticipated learning outcomes. The purpose of this study is to investigate the impacts of contextual colors on student’s perception of interior spaces and to validate previous related studies that emphasize on colors as a media to convey meanings that affect behaviors and students’ perception as well. Accordingly, the objective of this study is to determine and validate previous related studies regarding the impact of background color on student’s perception. Meanwhile the study evaluates the previous relevant models in order to validate or reject previous assumptions. The study concentrates on quantitative survey method using in depth questionnaire to determine student’s perception at UHD-University of Human Development, Sulaimani. Seven Colors from Munsell color system (yellow, green, blue, purple, white, and black, grey) are applied in the test in order to indicate the students’ perceptual status. The results show that cool colors like white, green and blue are mostly recommended for educational spaces. These colors affected positively the perception of respondents and add feeling of hope, curiosity and satisfaction to the group. In contrast dark colors (black and grey) are indicated as colors of worry and fear. The findings demonstrate that environments colors play an important effect on student’s perception. The study concluded that colors affect the behavior, performance and mood of the space users.

The main objective of this research is to investigate the effect of corroded steel bars on the ultimate flexural capacity of reinforcement concrete beams. The experimental work consists of four RC beams with dimensions (150×200×1200) mm tested under two-point concentrated loading. The major parameter of the current research is corrosion period (5,10,20) days. The amount of longitudinal and transverse reinforcement, concrete strength and, the other parameters were kept constant for all samples. The comparisons between specimens are based on the visual cracking loads, ultimate loads, deflection, cracks pattern and mode of failure. Results showed that visual first cracking load, and ultimate loads of corroded RC beams were decreased with increase corrosion durations relative to the control beam as a result of the corrosion process. The mode of failure was flexural failure for all specimens. Corrosion caused decreasing percentage in weight of steel bars and cross-sectional area of longitudinal steel bars. This percent increased as exposure time to corrosion process increased by 8.5% and 28.39% for 20 days respectively.

This article investigates the behaviour of strengthened concrete columns using jacketing ultra-high-performance fiber reinforced concrete (UHPFRC) and carbon fiber-reinforced polymer (CFRP) under uniaxial loaded. The jacket was connected to the column core using shear connectors and (CFRP) fixed as a strip on the tension zone between the column cores and the jacketing. Seven column samples of square cross-section (120 x120) mm at the midsection with overall length of 1250 mm were cast using normal strength concrete (NSC) and having similar longitudinal and transverse reinforcement. The samples were made and tested under axial load at eccentricity equal to 120 mm up to failure. Test parameters were the thickness of jackets (25 and 35) mm and the width of CFRP (0,8, and 12) cm. Column specimens were tested, one of them was reference without any strengthening, and the other specimens divided into two groups (A, and B), and each group included three specimens based on the parameters. Group (A) has UHPFRC jacket thickness 25 mm and CFRP width (0,8, and 12) cm respectively, and group (B) has UHPFRC jacket thickness 35 mm and CFRP width (0,8, and 12) cm respectively. The outcomes of the article show that increasing the thickness of jacket, and width of CFRP lead to increase in the load carrying capacity about (110.5%,168.4%, and 184.2%) for group A, and (157.9%,226.3%, and 263.2%) for group B compared with the reference column due to delay in the appearance of cracks and their distribution. The mid-height lateral displacement of columns was decreased about (66.6%,42.3%, and 35.9%) for group A, and (46.15%,38.46%, and 32.3%) for group B, also the axial deformation of specimens decreased about (71.7%,60.86%, and 55.86%) for group A, and (65.5%,60.5%, and 53.4) for group B compared with the reference column. The ductility of columns that were strengthened with UHPFRC jacket only was increased about (13.67%,19.66%) for thickness(25,35) mm respectively, because of that UHPFRC jacket was contented on steel fibers, and the percentage decrease of ductility was about (5.1%,and 12%) for group (A), (1%,and 9.4%) for group (B) when bonded CFRP in the tension zone with width (8 ,and 12) cm respectively. The results show improvement in the initial and secant stiffness when, increased the thickness of jacket, and width of CFRP because of increase in the size of columns and improvement in the modulus of elasticity. The toughness increase was about (273.97%,301.55%, and 304.5%) for group A, and (453.69%,511.93%, and 524.28%) for group B compared with the reference column because of increase in the size of specimens and delay the appearance of cracks.

Owing to the increasing population in Kirkuk, Iraq and the consequent rise in the production of waste, alongside with global warming caused by an increase in the greenhouse gases concentrations, a high level of emissions was observed at the landfill site near Kirkuk. These emissions can be transmitted by the wind over considerable distances and adversely affect the environment and individual health. In this study, two pilot scale columns were built to investigate different options for achieving sustainability by reducing long-term landfill emissions. Each reactor was packed with (8.5) kg of shredded synthetic solid waste (less than 5 cm) that was prepared according to an average composition of domestic solid waste in the city of Kirkuk. The main result of this study was that the pretreatment of the waste may shorten the transition time for active methane development and increase the methanogenesis of the landfill site and also affects COD removals efficiencies which were 19.11% and 66.53% for columns A and B respectively.

The study consists of two stages: the first one is to improve the gypsum soil with cement or calcium chloride and the second stage is to expose these soil specimens to series of wetting and drying cycles .Three soil specimens were taken and marked as (A,B and C) with gypsum content (47, 32 and 23)% respectively .The results show that cement additive increases the cohesion of soil specimens to 50% and collapse potential decreases with 65% and soil specimens improved with calcium chloride increase the cohesion up to more than 70% and collapse potential decreased about 70%. In the first cycle for wetting and drying cycles for soil specimens improved with cement the cohesion decreases about 25% and stays with the same ratio of the decreasing along the other cycle up to twelfth cycle. Collapse potential remains with the same value and is not affected by cycling of wetting and drying. In the first cycle for soil specimens treated with calcium chloride there is no effect in the first cycle whereas in the fourth cycle the cohesion increased by 60% and in the eighth cycle the cohesion decreased 8% and remains stable until the twelfth cycle. Collapse potential increases from one cycle to another by (30-50) % for all soil specimens.

This paper represents an experimental investigation of the layered concrete beam. It contains studying the possibility of using the mortar intervention with layers of glass fibre at the tension zone in a loaded supported concrete beam. To produce a beam with less weight than the beam with all Normal concrete and detecting the effect of this replacement on beam properties. A rectangular beams section (150*200*1000)mm cast with NSC (normal strength concrete) at compression zone and mortar with layers of 3D glass fibre used as a part of the tension zone. The produced beams are layered beams with a lighter weight than the homogenous RC beam. Three deferent levels of the replaced layers (1/3,1/2, and 2/3 of the beam thickness) were studied, all beams were tested under Two point load till failure.
The maximum load capacity result shows an apparent lowering in the load capacity of the beam, but as the lightweight layer increases, this lowering in the load capacity becomes less. for (1/3,1/2 and 2/3) of the beam thickness replace with mortar and 3D textile fibre, the lowering percentage of failure load compare with the homogenous reinforced concrete beam are (33.04%, 27.18%, and 19.73%), and the lowering in weight is (5.45%%, 9.07%, and 12..92%)
for the same sequence, respectively.
Stiffness, ductility and toughness of all beams are tested. An apparent lowering in the stiffness value of the layered beams is recorded with the reference ones. At the same time, it shows an increase in the toughness and toughness value.

The issue of upgrading and strengthening the reinforced concrete (RC) infrastructure has become of great importance. Recently, textile-reinforced mortar (TRM) was used in the field of structural strengthening. In the current study, using of TRM for flexural retrofitting of one-way reinforced concrete (RC) slabs was experimentally and theoretically investigated. The parameters examined included; the number of TRM layers (1, 3, 5 layers) and the strengthening configuration fully and partially). For this purpose, eight specimens were prepared and tested under three points- loading up to failure. The result showed that the TRM increases substantially the flexural capacity of RC slabs. The highest flexural capacity increase recorded was 103 %. It was also noted that increasing the number of retrofitting layers resulted in different increases in the flexural capacity. It was also shown that the strengthening configuration plays an important role in the effectiveness of the technique. The fully covered approach showed higher loading capacity than the partial cover technique provided that the same TRM layer is applied. Finally, the ultimate moment of the strengthened specimens was calculated theoretically and compared with that obtained experimentally. The results of calculations showed a good agreement between the theoretical and experimental results.

The cement plants in the Kurdistan Regional Government of Iraq (KRG) have made a considerable contribution to the economy of the region and almost dominated the cement market in the entire region and middle and south of Iraq. The cement plants as a part of KRG’s industrial sector needs to consider strategic planning, through this research the condition and quality of the cement plants in KRG have been evaluated, using Strengths, Weaknesses, Opportunities, and Threats analysis (SWOT Analysis) technique as a strategic planning tool to demonstrate weakness points and strong points in the cement production process and to review opportunities to turn weaknesses into strengths while identifying the challenges facing this process and suggesting strategies to develop the cement plants. The main aim of the current study is to strategically evaluate, plan, and improve cement plants in KRG through the application (SWOT Analysis Technique). To achieve the study objectives, the methodology consists of a literature survey and field survey; including Interviews, field visits, data collection, presentation, analysis, and discussion of the results. In this study the reality of cement production in Iraq and Kurdistan region of Iraq has been demonstrated, the research sample was Gasin Cement Company (GCC) located in Sulaimaniya Governorate, SWOT analysis has been conducted to study the reality in the plant, some strong points, weakness points, opportunities, and threats have been founded. As a strong point; the quality of cement in GCC is high then as a weakness point Absence supervision on contractor’s work, after that as an opportunity Iraqi government has prevented the import of cement since 2016, finally as a threat the fluctuation of oil price does have dangerous effects on the cement market.

This study was conducted to compare water surface profiles with standard ogee-crested spillways. Different methods were used, such as (experimental models, numerical models, and design nomographs for the United States Army Corps of Engineers, USACE). In accordance with the USACE specifications, three different models were constructed from rigid foam and then installed in a testing flume. The water surface profile has been recorded for these models with different design heads. For modeling the experimental model configurations, a numerical model based on the smoothed particle hydrodynamics (SPH) technique was used and is developed to simulate the water surface profile of the flow over the ogee-crested spillway. A 2D SPHysics open-source software has been used in this study, using the SPH formulation to model fluid flow, developing the SPH boundary procedure to handle open-boundary simulations, and modifying the open-source SPHysics code for this purpose. The maximum absolute difference between the measured and computed results of the water surface profile for all head ratios of (H/Hd), does not exceed 4.63% at the crest region, the numerical results for the water surface profile showed good agreement with the physical model results. The results obtained experimentally and numerically by SPH are compared with the CFD results in order to be more reassuring from the results. Additional comparisons were made using interpolated data from USACE, Waterways Experiment Station (WES), and design nomographs. The SPH technique is considered very promising and effective for free surface flow applications.