Anbar Journal of Engineering Sciences

The construction of pavement layers on subgrade soil with good characteristics decreases the
thickness of these layers, which in turn lowers the cost of building and maintaining roadways.
However, it is impossible to avoid constructing pavements on unsuitable subgrade due to a
number of limitations. Using conventional additives like lime and cement to improve subgrade
properties results in additional costs. As a result, utilizing by-products (cement kiln dust and
reclaimed asphalt pavement) in this field has benefits for the environment, economy, and
technology. Large amounts of cement kiln dust (CKD), a by-product material, are produced in
Portland cement factories. On the other hand, large amounts of reclaimed asphalt pavement
(RAP) are accumulated as a result of the rehabilitation of old roads. This paper discusses using
CKD and RAP to improve the characteristics of poor subgrade layers by conducting a series of
Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) tests on samples of
natural soil and soil stabilized with different percentages of CKD and RAP with different curing
times to investigate their impacts on soil properties. The curing was carried out by wrapping the
stabilized samples with several layers of nylon and then placing them in plastic bags at room
temperature. The compaction results illustrated that the addition of CKD increases OMC and
decreases MDD, in contrast to RAP, which decreases OMC and increases MDD. The addition of
CKD and RAP led to a significant and unexpected increase in the CBR values. The results show
that the soaked and unsoaked CBR values improve from 3.4% and 12.1% for natural soil to
220.1% and 211%, respectively, after adding 20% CKD and curing the samples for 28 days. Also,
the addition of 25% RAP to soil-20% CKD blend increased the soaked and unsoaked CBR values
to 251% and 215%, respectively. All the additions resulted in a significant reduction in swelling.

The promotion and activation of creativity in children is extremely valuable due to their age
growth. All types of environments, such as geographical, social, physical, and cultural environments, have a huge impact on children's development. Many studies have discussed the role of
the environment in general in the creativity and development of children. However, the effect of
the physical environment specifically seems to be disregarded. Nowadays children spend a lot of
their time in kindergarten, thus the physical environment of kindergarten affects the children's
development and creativity. It is noticed that at the kindergartens of Erbil city, the majority of
the factors that contribute to creativity have been disregarded. The kindergartens are more of
an academic institution than a place where children can be entertained or encouraged to be creative. In this study, qualitative and quantitative methodologies are applied to analyze the interior
spaces of kindergartens in Erbil city. This paper seeks to create a content environment that encourages children to improve their abilities and potential skills. The found results prove that the
physical environment factors are effective and significant in increasing children's creativity in
kindergartens

Composite pressure vessels (i.e. types III and IV) are widely used for compressed natural gas
(CNG) vehicles, as storage cylinders to reduce the weight while maintaining high mechanical
properties. These vessels can achieve 70-80% of weight saving, as compared to steel vessels
(type I). So, prediction of first ply failure and burst pressure of these vessels is of great concern.
Thus, this paper involved a review of literature regarding the first ply failure and burst pressure
of composite pressure vessels (types III and IV). The review included the researches related to
the simulation, mathematical modeling, and experimental analysis. The study focused on
simulation-related research more than others due to the complexities of mathematical
modeling of such problems in addition to the high cost of experimental tests. The results
indicated that the stacking sequence of layers, vessel thickness and the type of selected
composites were the main factors that mainly affect the vessel burst pressure performance.
Accordingly, the optimization in the vessel structure (composite fabric architecture)
parameters plays an important role in the performance of burst pressure. This in turn will lead
to a high vessel durability, longer life-time and better prediction of burst pressure.
Furthermore, the study showed that the prediction of first ply failure is more important than
burst pressure knowledge of pressure vessels because it gives an initial prediction of vessel
failure before the final failure occurrence. This in turn, may prevent the catastrophic damage of
vessel

Identifying key factors affecting of the projects objectives in
Baghdad Province by using experts interview technique

The cooling system of a car engine effects strongly the efficiency of the car engine so many
studies were presented to enhance the cooling system of the car. The components of the cooling system are radiator, water pumps, fan, shutters, thermostats, expansion tanks/storage
tanks, water pipes, water temperature gauges, etc. Among these components, the radiator
considers the primary key to enhancing the efficiency of the car engine. Many studies were
achieved to enhance the efficiency of car radiators by using different nanofluids as a coolant
are discussed in this literature review study. These previous studies investigated various
kinds of nanofluids such as Al2O3, CuO, TiO2, SiO2,and ZnO with different base fluids. Nanofluid
concentrations, nanofluid temperature, and nanofluid flow rate were studied by previous
studies eleven years ago.

Indeed, there are many hydrology variables influence on the operating of dam and reservoir
system. Thus, modelling of dam operation is a complicated issue due to the nonlinearity of such
hydrological parameters. Hence, the identification of a modern model with a high capacity to
cope with the operation of the dam is extremely important. The current research introduced
good an optimization algorithm, namely Genetic Algorithm (GA)to find best operation rules. The
main aim of the suggested algorithm is to minimize the difference between irrigation demand
and water release value. The developed algorithm was applied to find operation rules for Timah
Tasoh Dam, Malaysia. This research used significant evaluation indexes to examine the
algorithms' performance. The results indicated that the GA method achieved low Vulnerability,
high Resilience and Reliability. It has been demonstrated that the GA method will be a promising
tool in dealing with the problem of dam operation

Productivity improvement in the manufacturing industry of piping is a key challenge facing
manufacturers in today's competitive markets. Improving productivity in the pipe manufacturing companies by implementing manufacturing principles that utilize simulation modeling
was the purpose of this study. To improve productivity, an approach that focuses on the workstations and workforces process was suggested. The suggested approach’s goal was to increase productivity by providing customer prerequisites and leaving some products for other
customers in the store. Based on the data has been gathered from the company of steel pipes,
Bansal Ispat Tubes Private Limited in India, a simulation model was utilized to enhance its
performance of operational. The investigation methodology consists of a simulation model,
acceptable distribution, and data investigation. By simulating individual workstations and
evaluating all relevant processes according to the data collected, the simulation model was
built. Actual employment data were gathered from the line of manufacturing and supervisory
workers, with observations carried out throughout the process of manufacturing. The used
method involves videotaping of the process and interviewing workers using a video-camera.
The superior continuous distributions were picked to fulfill a convenient statistical model.
The results could be helps to ameliorate the manufacturing industry productivity. Furthermore, the outcomes could assist to solve the problems of scheduling in pipe manufacturing
"simulating and modeling" which reveals active ways in enhancing pipe manufacturing
productivity. Consequently, the findings might support well competition among companies

This study aims to improve different properties of sustainable self-compacting concrete SCC
containing treated and modified polyethylene terephthalate PET fibers. For this purpose, gamma
ray surface treatment and geometric modification were utilized for the used PET fibers. Concrete
fresh properties include slump flow, T500mm, L-box and sieve segregation while mechanical
properties include compressive, split tensile strength, flexural strength, static modulus of
elasticity and impact strength. Further, physical properties and related durability properties
comprise dry density, ultrasonic pulse velocity, porosity and water absorption. The results
obtained demonstrated that the treatment and the modification used for the PET fibers slightly
reduced the fresh properties of produced sustainable SCC (slump flow, T500 mm, L-Box and sieve
segregation).However,they were within the limits ofthe SCC specification as reported in EFNERC
guidelines. Further, concrete hardened properties in terms of compressive strength, splitting
tensile strength, flexural strength, modulus of elasticity, impact strength, ultrasonic pulse
velocity, decrease in the dry density, decrease in porosity and water absorption increased
significantly

This paper investigates the possibility of strengthening Reinforced Concrete (RC) beams under
pure torsion loadings. The torsional behaviour of strengthened RC beams with near-surface
mounted steel and CFRP bars was investigated. The verification with the experimental work was
performed to ensure the validity and accuracy which revealed a good agreement through the
torque-rotation relationship, ultimate torque, and rotation, and crack pattern. This numerical
study included testing of thirteen specimens (one of them was control beams while the
remaining 12 were strengthened beams) with several parameters such as mounting spacing and
configuration. The analytical results revealed that the addition of NSM rebar redistributed the
internal stresses and enhanced the ultimate torsional strength, torque-rotation capacity,
ductility, and energy absorption of the concrete beams. Most of the strengthened beams revealed
the appearance of the cracks at a phase less than the reference beam by an average of (9%).
Concerning the NSM strengthening, the CFRP bars provided a higher enhancement ratio when
compared with the beams that strengthened with NSM steel rebar especially for the
strengthening space equal to 130 mm and more. The ultimate torsional strength increased by
(3.5%) and rotation decreased by (4%) approximately when the steel rebar was replaced by the
carbon bar. The ductility and energy absorption of the analysed beams showed that the
strengthening enhanced the ductility of the twisted beams. The ductility values varied according
to the method of strengthening used, as it showed the highest values of the beam that was
strengthened small spacing.

In this article, an experimental study of the single-pass hybrid PV/T collector is conducted in
the climatic conditions of Fallujah city, where the experimental results are compared with a
previous research to validate the results. The effect of changing the angle of inclination of the
hybrid collector (PV/T) and its effect on the electrical power in the range (20°-50°) is studied.
The optimum angle of the collector is found to be 30°, which gives a maximum electrical power
of 58.8 W at average solar radiation of 734.35 W/m2. In another experimental study with
different air flow rates ranged from 0.04 kg/s to 0163 kg/s, where it was found that the maximum
electrical power of 57.66 W at an air flow rate of 0.135 kg/s, while the maximum thermal
efficiency reaches 33.53% at an air flow of 0.163 kg/s at average solar radiation of 786 W/m2.