Layth AbdulRasool Mahdi Alasadi

In this paper, laboratory models were simulated by the software of Computational Fluid Dynamics (CFD) to develop an empirical formula that describes a relationship between the width of a gradual contraction in a rectangular channel under critical flow conditions within the zone of contraction. Four laboratory models with different widths of contraction: the first was 14 cm, the second was 16 cm, the third was 18 cm, and the fourth was 20 cm, were modelled in the CFD v18.2 program. A virtual flume having a cross-section of 30 cm in width and 60 cm in height, is also created. The length of contraction is chosen as 1 m, located at 0.75 m from the beginning of the channel, taking into account that the channel is gradually contracted at a 45o for all models. Nine values of discharges were applied to each model :20.5 l/s, 25 l/s, 30 l/s, 33.5 l/s, 38.6 l/s, 40.5 l/s, 45.2 l/s, 50 l/s and 57.6 l/s. Several measures of water depths were taken at different cross-sections along the field of flow. The first was at the upstream of contraction (y1); the second was at the middle of the section of contraction where the critical flow occurs (yc); the third and fourth were located at the outlet of contraction when the hydraulic jump occurs (i.e., initial depth, yi and sequent depth, ys). Froude number (Fr) was measured for each case. All factors (y1, yc, yi, ys, and Fr) were processed to obtain non-linear coefficients using Buckingham's method (π – theorem) for dimensional analysis. Then, these coefficients were used in the software (SPSS v25) to derive a non-dimensional relationship between the non-dimensional width (W/y1) and the other non-dimensional parameters. The developed relationship yielded a good coefficient of determination (R2).

This investigation aims to improve some of the mechanical properties of concrete such as compressive strength, flexural strength, and modulus of elasticity, by using different percentages of polypropylene fibers, and also studying the durability of concrete for freeze-thaw cycles. the study shows a small increment in compressive strength due to adding fibers which were 28.3% compared with increment in flexural strength which was perfect (about 191%), modulus of elasticity also increased by adding fibers. The durability of concrete against freezing-thaw cycles for all mixes was studied. Fiber-reinforced concrete shows more durability against freezing-thawing cycles and less reduction in strength compared with reference mixes without fibers,21.5% reduction in strength for optimum polypropylene fiber concrete while the reduction in strength for normal concrete was found 54.2% in this study.

The study aims to improve some mechanical properties like compressive strength, tensile strength, modulus of elasticity and flexural strength of polymer modified concrete (PMC). This improving for PMC done by using waste iron filling as replacement from fine aggregate. waste iron filings and chips used in this research as percentages from sand ranged from 0 % to 40 % , the compressive strength of ordinary polymer concrete increase from 32.2 MPa to 41.81 MPa by 40% replacement of sand with waste iron filings and chips, tensile strength increased also from 2.83 MPa to 4.23 MPa by 40% replacement also. Flexural strength increased from 3.7 MPa for reference mix to about 7.1 MPa for mixes with 40% replacement, modulus of elasticity increased from 21087 MPa to 25233 MPa by using maximum percentage of waste iron filings. There is a slight increment in mechanical properties of polymer modified concrete after 30% ratio of waste iron filings and chips. Also research includes mixes modified with larger dosage of super plasticizer and less water/cement ratio to improve mechanical properties of PMC.

The objective of this paper is to calculate the influential properties of concrete. These are the dynamic properties of sustainable concrete in the situation in which metal waste can found within its components. Growing the rate of pollution in the world, a fast decrease of the original resource, the requirement for utilization more areas of natural land, and increase the price of the newly available area are the reasons that make the researchers give great attention to the new concrete (green concrete) and destruction of unwanted material in the green mix. The concept of reuse aimed at sustainable structures was implemented within the current paper through consuming metal waste of cans and bottle caps in concrete. The waste materials were consumed in two modes; at 1st mode, it was applied in the role of fibres and mixed using 15% by weight of cement. On the 2nd mode, it was applied as coarse aggregate with 25% replaced by volume. The procedure includes testing 4 concrete mixes. The estimated properties were the flexural and compressive strengths, besides modulus of elasticity. Adding bottle caps (waste materials fibres) in concrete led to enhancement in strengths. The use of walls of cans (waste materials fibres) in concrete reduced the strengths. While in the case of compacted bottle caps plus pull-tab of cans (waste materials aggregate), concrete mechanical properties a little below the reference mix. The dynamic properties of concrete contain these types of waste under impact load were determined. As known, the dynamic properties are so helpful in the strategy that deals with civil constructions put in danger of impact loads like runways, gas explosion, etc. CEB-FIP (2010) code provides wide-ranging formulas to predict the strain change of concrete. The dynamic properties are determined by this code with consideration strain level between (10-2-100). In this range, dynamic loads in the civil constructions at the level of quasi-static strain were predicted.

Reinforced concrete foundation, rigid pavements, and other structural members with attachment with ground or salty water like piers or retaining walls and others, subjected to chloride and sulfate salts attacks and that leads to damaging the structures or at least reduce durability, some concrete admixtures like waterproofing admixtures or polymers reduce permeability and increase mechanical properties and also durability. This research aims to improve the quality of concrete and reducing corrosion of steel reinforcement by using integral waterproofing admixture, styrene-butadiene rubber (SBR) and polypropylene fibers. mechanical properties such as compressive, flexural strength highly improved in this study. The reduction of weight of steel reinforcement by subjecting reinforced concrete specimens to chloride water (6% concentration) was 2.61 % for ordinary reinforced concrete and by using waterproof –polymer concrete with poly fibers, the reduction was less and its value was 0.93% and that was for 6 months’ exposure, and for 1-year exposure, the reduction in steel reinforcement weight was 4.72% for ordinary concrete and 1.4% for waterproof concrete.

The disposing of wastes is a serious challenge. The landfill disposal is occasioning in high charges and environmental harms. If existing development continues, waste creation will develop by 5% each year. The employing of waste in construction appears to be an appropriate way of facing this challenge. Within this investigation, the use of a waste of paper office to produce sustainable mortar was achieved. Mortar mixes covering different contents of the waste were equipped. These contents were (0,10, 20, 30, 40 and 50) % as an alternate percent of the volume of the sand. To assure that the mortar has the proper mechanical properties, characteristics for instance workability, compressive strength, flexural strength, density, water absorption, fire resistance, and ultrasonic pulse velocity were fixed and equated with a reference mix.

The disposing of wastes is a serious challenge. The landfill disposal is occasioning in high charges and environmental harms. If existing development continues, waste creation will develop by 5% each year. The employing of waste in construction appears to be an appropriate way of facing this challenge. Within this investigation, the use of a waste of paper office to produce sustainable mortar was achieved. Mortar mixes covering different contents of the waste were equipped. These contents were (0,10, 20, 30, 40 and 50) % as an alternate percent of the volume of the sand. To assure that the mortar has the proper mechanical properties, characteristics for instance workability, compressive strength, flexural strength, density, water absorption, fire resistance, and ultrasonic pulse velocity were fixed and equated with a reference mix.

Box culverts are the monolithic unit build to pass across railway lines, roadways, etc. earthworks are made to balance the discharge water on both sides. Box takes different types of loads created by a cushion, traffic, water, soil, etc. This paper deals with the optimum design of box culvert by using Newton's-Raphson Method and AppDesigner in MATLAB Software R2017a and studies the design parameters such as the influence of depth of earth fill at the top slab of the culvert, earth pressure, factor Dead Load, Live load, effective width, etc. In this paper, the study of the box-culvert with normal and minimum cushion analyzed for different classes of loadings and conclusions made on the basis of Newton's-Raphson Method normal and minimum cushion and normal cushioning cases.

Nowadays, applying new materials is widely used in concrete construction to study their effects in enhancing the properties and the durability of concrete. This research includes studying the using of manufactured aggregate, which is so-called '' Anti-slip sand '' in specific proportions to know its influence on strength properties of normal strength hardened concrete which involves compressive strength, flexural strength, tensile splitting strength, and density. Anti-slip sand at different rates of (25%, 50%, 75%, and 100%) replaces the natural sand in the concrete mixture to investigate its effect on the properties of concrete. The study shows that the best results of concrete properties are found when replaced the natural sand by 100% of anti-slip sand. Compressive, flexural and tensile strengths of concrete are increased with increment ratios of (44%, 40%, and 20%) respectively compared with other concrete mixture contains only natural sand. In addition, the study shows that the density of hardened concrete is decreased from 2420 kg/m3 in concrete with 100% natural sand to 2360 kg/m3 with a decrement ratio of 2.5% in concrete with 100% anti-slip sand.

The use of waste aggregate in concrete is very important because of that decrease the total cost of concrete and lead to a more clean environment. This research aims to study the mechanical properties such as compressive, tensile and flexural strength and also the modulus of elasticity for concrete containing waste glass as coarse and fine aggregate and improved also with integral waterproofing admixture. The study shows the improvement in mechanical properties due to using waste glass only and waste glass with integral waterproofing admixture, compressive strength increased from 27.3-35.8 MPa by total glass replacement but using both glass and waterproof lead to rise compressive strength to 54.38 MPa also other mechanical properties increased highly by using glass and waterproofing admixture .

This study aims to improve the mechanical properties of waste aggregate concrete by using steel fibers and waterproof liquid admixture. The study shows that using waste rocks and glass aggregate improves mechanical properties comparing with reference mix, using steel fibers increase compressive strength, tensile strength and much higher values in the flexural strength. Using waterproof admixture enhance mechanical properties of steel fiber concrete and give higher strength concrete,compressive strength increased from 43.33 MPa for steel fiber concrete (with waste aggregates) to 57.82 MPa, tensile strength increased from 4.64 MPa to 5.83 MPa , flexural strength increased from 8.95 to 12.73 MPa and also the modulus of elasticity increased from 29801 MPa for steel fiber-waste aggregate concrete to 33879 MPa for waste aggregate-steel fiber concrete improved with waterproof admixture.

The current study offers the finite element application on a rigid apron pavement to get developed tensile stresses and strains due to huge aircraft gross weight. FAAFIELD software was utilized to design the apron layers for International Al-Najaf airport. The ANSYS 14 finite element software program is applied in the testing of the design parameters of rigid pavement airport structures. Two 3D-FEM are utilized to model plain and reinforced concrete slab supported by several elastic springs which rigidity is presented by the modulus of subgrade reaction denoted by (k). The extreme tensile stress has been gotten at the beneath of concrete panel slab under various cases of material properties and heavy aircraft landing gear loading. Furthermore, statistics model related maximum tensile stress as the dependent variable with elastic modulus and thickness of the concrete panel, and modulus of subgrade reaction has been developed by using SPSS version 23.

This research aims to study the effect of silica fume and polymers (Styrene Butadiene Rubber (SBR)) on absorption and some mechanical properties of concrete like compressive, tensile and flexural strength of concrete containing waste aggregates. The reference mixes having waste aggregates (crushed glass) as coarse aggregates to decrease the cost of concrete and also increase strength. The effect of silica fume only on concrete was given 61% increment in compressive strength, but with polymers together give about 72% increment, flexural strength increased from 3.8 MPa for reference mixes to 10.5 MPa for silica fume mixes and 12.3 MPa for polymer-silica mixes. The absorption decreases from 6.01% to 2.85% for silica mixes and to 1.5% for polymer-silica mixes.

Commingle with garbage and/or by- output materials in build manufacture such as the making of hot asphalt concrete mixtures supply worthy interest on the way of ecological, economic standpoint. Accordingly, in this experimenter research, it was scrupulous for using Ground Granulated Blast Furnace Slag (GGBFS) in state traditional metal filler in hot asphalt mixtures. The mechanical characteristic was rating by lineal Marshall Stability & Indirect Tensile Strength tests. however, moisture harm and long-range ageing were investigated by locating Index of retained Strength (IRS) & Mean Marshall Stability Ratio (MMSR), respectively. The empirical outcomes have presented a considerable refinement in the mechanical properties and a fundamental promotion in the durability of the generated mixtures i.e. Asphalt Concrete Mixtures with GGBFS as a mineral filler (GGBFSAC) in rapprochement with the control mixtures that were infectious by ordinary Portland cement (OPC) as a mineral filler (OPCAC). As an outcome of this research, GGBFS can be united in state classical mineral filler in asphalt concrete mixtures especially in the region where there is a large GGBFS waste.

lean concrete mixes is a concrete mix with low cement content and high percentages of aggregates, it used in several works such as the blinding concrete under foundations and as levelling course below footings or in mass concrete such as dams. The need to make this layer of concrete in more strength and more durable is important, using polymers such as styrene butadiene rubber ( SBR ) in concrete improve the mechanical strength of concrete and durability and make concrete permeability very low, and also using silica-fume powder leads also to improve the strength of concrete. This investigation studies the effect of using styrene butadiene rubber polymer in different percentages and also silica fume to lean mixes to improve the mechanical properties. Mixes with 10% polymers gives the highest values of mechanical properties with 10 % silica fume , it gives average compressive strength of 24.3 MPa while in reference mix give 13.2 MPa , the flexural strength also increased from 1.24 MPa for lean mixes to 4.8 MPa to silica-polymer mixes .the main reason for using polymers and silica fume is because of these two materials reduce the heat of hydration during mixing and casting concrete, so that is very important in mass concrete.

Fiber reinforced concrete is widely used in concrete structures, it has several benefits like increasing tensile, compressive, flexural strength and modulus of elasticity and also increases ductility and toughness of concrete. This research aims to improve the mechanical properties of concrete by using polyethylene fibers obtained from plastic cans, higher tensile and flexural strength obtained by using this type of fiber. This Polyethylene fiber is more durable than other types of fibers since it does not rust with time like steel fibers types. Compressive strength in this research increased from 37.4 MPa to 49.3 MPa, flexural strength increased from 3.5 MPa to 9.89 MPa, and tensile strength increased from 2.9 MPa to 5.1 MPa.

Permeable paving has been vastly utilized as an alternate to traditional impervious hard surfaces, such as street, parking lots, sidewalk and pedestrian areas. This leads to several rain water management and environmental advantage. Therefore, this study has focused on brief the wide-range of permeable pavement systems These types of permeable pavements have been reviewed in addition to the usefulness of each kind. The results indicated the potential of using such kind in different locations in Iraq is more likely such as Al-Najaf city. Several points of soil investigations have been conducted by previous studies within Al-Najaf city (boundary of Al-Najaf Municipal) prove that Al-Najfa soil is sandy soil. These tested points also demonstrate that the soil characteristics of the city are so suitable for such type of pavement.

Pipes are manufactured primarily through the extrusion process. One of the material extrusion processes in recent digital manufacturing is additive manufacturing’s fusion deposition modeling. Pipes are made from various materials such as metal and plastic/polymers, and the main challenge has been in selecting the pipe material for the customized application. For the creation of water-passing tubes, this research has chosen appropriate carbon-reinforced polymers that can be used with filament made of polyether ether ketone (PEEK) and polyethylene terephthalate glycol (PETG). For this goal, the analytical hierarchy process, also known as the AHP, is used to choose the best material based on factors such as cost, temperature resistance, printing speed, and mechanical properties of the material. The results revealed that PEEK-CF is a better material for the customized impeller application than PETG-CF. The PEEK-CF obtains the higher priority value of 0.6363, and the PETG-CF obtains 0.2791. This decision-making technique can be used to select other comparable customized applications.

In this article, polymer-modified concrete was studied to present the effect of using additives on its mechanical properties. This will be achieved by employing a high-performance super plasticizing admixture that significantly enhances polymer-modified concrete mechanical capabilities. The study indicates that the polymer styrene-butadiene rubber (used increases concrete mechanical properties by 10% by weight. When the dosage exceeds 10% by weight of cement, the compressive, tensile, and flexural strengths of polymer-modified concrete are diminished. With the addition of a superplasticizer with a ratio of 1.2%, regular polymer-modified concrete compressive strength has increased from 34.3 to 42.9 MPa for a 10% polymer/cement ratio. Additionally, this superplasticizer enhanced the Material's flexural and tensile strength.

Pollack Periodica is an interdisciplinary, peer-reviewed journal that provides an international forum for the presentation, discussion and dissemination of the latest advances and developments in engineering and informatics. Pollack Periodica invites papers reporting new research and applications from a wide range of discipline, including civil, mechanical, electrical, environmental, earthquake, material and information engineering.The journal aims at reaching a wider audience, not only researchers, but also those likely to be most affected by research results, for example designers, fabricators, specialists, developers, computer scientists managers in academic, governmental and industrial communities. The scope of the journal includes, but is not limited to the following scientific fields: * numerical analysis and simulation of engineering structures and systems; * design theory of structures; * fluid-structure and soil-structure interaction analysis; * experimental techniques; * material modelling, composite materials; * computer-aided design and methodology; * sensitivity and optimisation methods; * probabilistic approaches; * advanced or innovative applications of computers to practical engineering problem; * software engineering and related hardware/software systems issues; * expert and intelligent systems applied in industry and governments. The journal publishes original research papers dealing with all aspects of systems and structures of engineering and information sciences, including theoretical and experimental research. Papers presenting research findings in a form suitable for practical use or papers by designers and fabricators dealing with issues bearing directly on research are especially welcome. Papers reporting work in progress will also be included provided the long-term practical implications of the research are evident.

Even though concrete structures are safer than steel structures in terms of fire resistance, the risk exists in concrete structures by spalling or exploding, especially in high-strength concrete. This study aims to produce a particular type of concrete using waste ceramics as fine aggregate and waste glass as coarse aggregate and compare data with normal aggregate concrete. Studies show that using waste ceramic and glass increases the fire resistance of concrete. After fire exposure in the control mix, the residual compressive strength was 10 MPa. The waste aggregate concrete was found to be 26.9 MPa after 800 centigrade exposures, which was an excellent result. Waste materials decreased construction costs and led to a clean environment.

The current study examines the flow characteristics under free flow conditions over a crump weir. The impact of the side slopes of the weir on the coefficient of discharge (Cd) is taken into account. Four physical models with crest heights of 0.15 m under free flow circumstances and four upstream side slope (1:3, 1:2.5, 1:2 and 1:1.5) were used to investigate the impact of various variables on discharge coefficient (Cd). Using the dimensional analysis technique, the elements influencing the crump weir's discharge coefficient were determined based on laboratory tests. For the same flow rate, Cd value decrease by decreasing upstream side slope. It notices that a decrease in upstream slope (from 1:3 to 1:2.5) reducing Cd value about (2.61 %), decrease upstream slope from (1:3 to 1:2) reducing Cd value about (4.16 %) and when decrease upstream slope from (1:3 to 1:1.5) reducing Cd value about (5.81 %).

Waste aggregate concrete is the most common roject in the world of construction. The waste materials are causing environmental pollution and hurting nature, the use of wastes give more clean nature and so that the use of wastes in concrete can solve these problems. This study aims to investigate the use of waste granite as coarse aggregate in concrete, studying also the use of waste concrete from old buildings as coarse aggregate, and then comparing between them. The study shows that waste black granite aggregate gives best results in compression and tensile strength, compressive strength increased from 33.6 to 43.9 MPa, Using waste concrete as coarse aggregate increased also compressive strength from 33.6 MPa for reference mix to 36.9 MPa with 100% replacement.

Spur-dikes are efficient hydraulic structures that are made for numerous purposes. They have one end on the stream bank and another extending into the current. As a result of the existing spur-dikes in the stream course, the local scour phenomena usually occur around them, leading to several predicaments which have been of great concern to the hydraulic engineers. For the present work, laboratory experiments were carried out to measure the scour depths around several spur-dikes located at different distances for the V-shaped one. The experiments were conducted using physical models installed in a non-curved flume with a bed with uniform cohesion-less sediment of a medium particle size (d50 = 0.7 mm). All the models were operated under the subcritical flow of clear-water conditions. The investigations include three spur-dikes (1, 2 and 3) and three distances between them (1, 1.5 and 2 of spur-dike length) as two countermeasures to minimize the local scour depths. The results showed that an increasing number of spur-dikes and the distances between them would decrease the scour depths within the limit of the present study. The experimental data were used to create a new formula of R2 = 0.954 that reflects a good agreement with the experimentally observed results.

About this journal Open Engineering publishes research results of wide interest in emerging interdisciplinary and traditional engineering fields. The journal is designed to facilitate the exchange of innovative and interdisciplinary ideas between researchers from different countries. Open Engineering is a peer-reviewed, English language journal. Additionally, each published article is widely promoted to researchers working in the same field. Aims and Scope electrical and computer engineering, civil and environmental engineering, mechanical and aerospace engineering, material science and engineering. https://www.degruyter.com/journal/key/eng/html

Journal of Materials Science Research and Reviews aims to publish high-quality papers in all areas including metals, ceramics, glasses, polymers, electrical materials, composite materials, fibers, all engineering materials, nanostructured materials, nanocomposites, and biological and biomedical materials. By not excluding papers based on novelty, this journal facilitates the research and wishes to publish papers as long as they are technically correct and scientifically motivated. The journal also encourages the submission of useful reports of negative results. This is a quality controlled, OPEN peer-reviewed, open-access INTERNATIONAL journal.

Heritage and Sustainable Development (HSD), ISSN 2712-0554 (UDC 62), is an open access journal with a single-blind peer review process, published online. The journal publishes a broad range of interdisciplinary papers (original research papers, short communications, technical reports, case studies, and reviews), related to business, management, accounting, architecture, engineering, environmental engineering, and sustainability. In order to maintain the highest standards of quality, all submitted papers undergo an initial evaluation by the Editors. If deemed appropriate for further review, they are sent to a single-blind peer review process. The journal provides cutting-edge content on key topics, making it a valuable resource for researchers, academics, students, and professionals globally. https://hsd.ardascience.com/index.php/journal

Open Engineering publishes research results of wide interest in emerging interdisciplinary and traditional engineering fields. The journal is designed to facilitate the exchange of innovative and interdisciplinary ideas between researchers from different countries. Open Engineering is a peer-reviewed, English language journal. Additionally, each published article is widely promoted to researchers working in the same field. Aims and Scope electrical and computer engineering, civil and environmental engineering, mechanical and aerospace engineering, material science and engineering. https://www.scopus.com/sourceid/21100375904