DIYALA JOURNAL OF ENGINEERING SCIENCES

n this paper, the effect of direct fire flame and steel fiber ratio on some mechanical properties and behavior of the relationship between load and deflection of rectangular reinforced concrete beams under the influence of fire exposure was studied. Concrete specimens were exposed to fire at temperatures ranging from (25-400 ºC). Three temperature levels of (200, 300, 400 ºC) where chosen for exposure duration of 2.0 hours. After conducting the test, it was found that increasing the proportion of steel fibers in percentages 0.5% to 1% and 1.5% decreases the mid-spandeflection at service load by 33%, 50% and 37.5 and increases the ultimate load by 36.36%, 41.6% and 53% respectively. After the beams are exposed to fire, it was noticed that the maximum crack width increases with increasing fire temperature.

n this study, two systems of bio-ceramic coating (45S5 bioactive glass and hydroxyapatite) were used in order to compare between them for biomedical applications. Each system consists from two layers of coating done by electrophoretic deposition (EPD) technique on 316L stainless steel material as substrate. Two types of biopolymers were used (Chitosan with Gelatin) as first layer of coating. Taguchi approach with L9 array was used in order to choose the best conditions (concentrations, voltage and time) for coating layers. Each system consists of two-layer (biopolymer (first layer) and bioceramic (second layer)) materials. The optimum parameters for first layer of biopolymer were (3g/L concentration, 20 voltage and 3 minute) while optimum parameters for second layer of bioceramic group (6g/L concentration, 30 voltage and 1 minute) for 45S5 BG system and (6g/L concentration, 40 voltage and 1 minute) for HA system. Zeta potential test were employed to measure suspensions stability. The tape test method was used to evaluate the adhesion between substrate and coating layers, the results show that the percentage of removal area for optimum coating layer (biopolymer, 45S5 BG and HA 8.06%, 10.668%, 6.01% subsequently). XRD inspection was used for identify the phases of coating layers. The Cyclic polarization test was used for evaluation of pitting corrosion resistance, the results show all layers gives good corrosion resistance but 45S5BG system gives the best corrosion resistance when compared with HA system.

Product modifications or replacement of old products with new and improved material items. Vehicle suspension systems are another area where these developments are carried out on a regular basis. More efforts are being made to improve the user's comfort. Appropriate combination of comfort riding attributes and economics in leaf spring production becomes an evident requirement. Many changes have been made to the suspension system throughout time in order to enhance it. Some of the most recent suspension system innovations include the invention of the parabolic leaf spring and the usage of composite materials for these springs. The implementation of composite materials by replacing steel in conventional leaf springs of a suspension system. Composite material having a lot of good properties like simple fabrication, low weight and low cost to performance. The purpose of this study is to investigate the structural properties of a hybrid leaf spring consisting of 95% Epoxy, 5% carbon, 5% glass fiber, and 5% hybrid carbon-glass fiber composite. The various specimens were produced using the manual layup method, specimen was subjected to tensile, fatigue and hardness tests, with all data reported. The experimental results showed an increase in tensile, fatigue life andhardness when the reinforcing fibers are applied. The best results of the mechanical test obtained when hybrid reinforcement was applied

Terrorist attacks have increased in the past few years in different countries. Explosionsare problem that has significant impact on human life, as well as the social and economicsituations. Engineers have designed targeted structures to mitigate blast effects.However, design blast-resistant systems is pricey and not suitable choice in most cases.Therefore, install blast barriers to protect occupants and instructedcan reduce casualtiesand losses. Most current studies have investigated the performance of multi-layercomposite blast barriers composed of advanced materials, which is not only costly, butrequire skilled labourto construct. The present study conducts numerical analysis of eco-friendlycomposite blast protectionwall to mitigate blast.The wall structure consists oftwo face-sheet of adobe brick and core layer of crushedrecycled aggregate. The analysisframework includes three different blast wall models using ABAQUS®. The explosivecharge of 1-kilogram TNT is placed at different standoff distances from 0.25 to 4.0meter in front of the wall. The authors conclude sustainable materials to design blastbarriers could be effective in reducing the intensity of explosions in certain blastscenarios. The thickness of the core layer and standoff distance have the maincontribution to identify the blast response of the blastwall. For instance, the calculatedout-of-plane displacement results showed when 1-kg TNT place at 0.5-m from the wall,and thickness of the core increases from 30-cmto 60-cm, the displacement decreases by38.74%. While the acceleration decreases by75% for the same range of increase ofthickness of the core layer. The present study calls researchers to investigate theperformance of low-cost, and environment-friendly materials to attenuate abnormalloads wether are man-made or natural hazards.

In Iraq, the construction industry is considered one of the main sectors that contribute strongly to the Iraqi economy. Documentation is a process of collecting documents from past and current works of corporations, then archiving and classification of information to become easy and useful for reuse in the future. The aim of this study is to investigate the reality of documentation in the Iraqi construction industry and how to improve archiving and classification of documents and how documentation can be useful used in contractor and consultant corporations. This research has been conducted through literature reviews followed by a field survey. 80 questionnaires were distributed to contractors and engineering offices. 70 useful questionnaires were received from respondents with an 87% response rate. The findings indicated that the construction projects in the Diyala governorate are applying documentation. The study found that foundations classified and updating the documents as printed and written files and computer files, but foundations lack computer programs and web models for easy archiving and discovery of documents, documentation system currently used doesn't prevent Confusing, conflict in schemas because they still used Auto CAD and paper documentation.The large number and accumulation of paper documents are also considered the most often problem in the documentation system currently used, and construction projects don't have a database for all information related to projects where, it is limited to cabinets full of paper documents, which causes a waste of time and effort when searching for any document or information related to the projects.The study recommended that companies and foundations have to increase cost and effort consumed in the documentation process, improve the owner and staff abilities in computer and web applications, assign a key person for collection and archiving project documents, establishing an internet website for companies,orusing cloud applications for storage of documents and sharing information.

The construction of airport infrastructures usually consumes huge amount of energy. In fact, the airport buildings are among the largest energy consumers entities due to their huge size and special operation pattern as well as their unique configuration that facilitate the large number of accommodated passengers. Despite the local energy shortage in Iraq in the last two decades, there is a quite scarce number of researches that deal with sustainable airport buildings. The aim of this research is to analyze the terminal building in Baghdad International Airport in order to find out the best set of modifications that result in an optimal energy consumption and least carbon dioxide emissions. The analysis was conducted by the use of Building Information Modelling (BIM) technology and the associated programs such as; Auto desk Revit 2021 and Auto desk Insight 360, in order to determine the optimal strategies by which the most applicable alternative construction materials and procedures are considered in order to obtain an environmentally and economically sustainable airport terminal buildings. By applying this analysis on Nineveh terminal building in Baghdad International Airport revealed that many alternatives are capable of making tangible reduction in the Energy Use Intensity (EUI). Such reductions are noticed when altering, in the optimum manner, the windows configurations in terms of size, glazing type, and shadings. The alteration of construction materials for walls and roofs also reduces the EUI. It was alsofound out that the change in lighting control systems and lighting efficiency may reduce EUI. But the major impact could be resulted when altering the Heating/Ventilating/ Air conditioning Systems (HVAC) in the optimum manner which reduces the EUI by 67.15kw/m2/year, and the proper use of photovoltaic panels which provides a sustainable electricity and reduces EUI by 57.08 kWh/m2/year. Accordingly; in the quest of the best procedure to develop a sustainable terminal building, it is highly recommended to alter the HVAC systems and the utilization of the photovoltaic panels on rooftops

The FiberMetal Laminates (FMLs) was studied and improved the mechanical properties were used for aircraft wing. The FMLs are consisting of metal sheets reinforced with fiber bonded by matrix phase. The FMLs consist of seven layers to produce the Hybrid composite materials that made from 2024-T3 Aluminuim sheets with carbon and glass fibers as reinforcement and bonded using adhesion materials that are locally manufactured from resole resin with adding using epoxy resin. By using the FMLs, the mechanical characteristics have been improved and the weight of the aircraft wing has been reduced. The mechanical characteristics have been improved comparing to other FMLs using commercial epoxy. The FMLs with carbon and glass fibers have high tensile strength and elastic modulus but low yield and elongation comparing with the FMLs of carbon fibers as a reinforcement. The flexural modulus and impact toughness is high for the FMLs with glass fiber comparing with jute fibers with adding using carbon fiber as areinforcement.The Aramid Reinforced Aluminum Laminates (ARALLs) have low fatigue strength than FMLs using carbon fiber as reinforcement. The FMLs are lower ratio of ultimate to yield strength and density than 2024-T3 Aluminum alloy that commonly used in aircraft wing.

The prediction of dam’sbreach geometry crucial in studies of dam breaking. The hydrographs characteristics of flood that resulting from breaking of dam is mainly depend on the geometry of breach and the time formation of breach.Five approaches(Froehlich, Macdonald and Langridge-Monopolis, Von thun & Gillete, USBR and Singh % Snorrason)was used in order to predict dam breach parameters(breach width, breach side slope, breach formation time).The Sensitivity analysis was performed in order to assess the effect of each parameter on the resulting hydrograph of the flood. HEC-RAS model was used to calculate the effect of each parameter on the hydrograph of the flood that resulted.The width of breach (????????????????), side slope (z) and formation time of breach (????????) increased by 25%,50%, 75% and 100% and decreased by 25%, 50% and 75%, respectively. Flood hydrograph was estimated at the dam site for each case. Sensitivity analysis was performed in order to check the effect of each parameter of breach and time of breaching. Sensitivity analysis was performed with Froehlich method with the mode of overtopping failure and maximum operating level at 107.5 meter above sea level. Result of sensitivity analysis show that peak discharge and time to reach it is adequately sensitive to breach side slope, highly sensitive to the breach formation time and less sensitive to breach width.

The currentwork investigates the behavior and strength of T-shaped cross section ring deep beams through a Finite element parametric study. Currently, ring diameter, loading type, concrete compressive strength and number of supportsare taken into consideration. It is found that increasing ring diameter of beam by 12.5-25% leads to increase the maximum positive moment, maximum negative moment, maximum torsional moment and midspan deflection by 1.1-2.2%, 2.2-4.3%, 3-6% and 16-33%, respectively, whilethe load ultimate capacity increases by 11-17%. The positive and torsional moments at midspan and midspan deflection decrease by 23-36%, 3-11% and 6-14%, respectively when the loading type varies from concentered to full uniformly load over a span length of 33, 50, 67 and 100%, respectively. In a related context, this change in load type leads the negative moment at support and the load ultimate capacity to increase by 2-21% and 6-85%, respectively. The midspan positive moment, negative moment, torsional moment and load ultimate capacity increase by 20.4-71.3%, 20-69.7%, 15.6-43.8% and 21-73%, respectively, whereas deflection decreases by 1.4-11%, when increasing the compressive concrete strength by 45-190%. Finally, it is found that the load ultimate capacity increasesby 82-348%, when number of supports increases by 25-100%, while torsional moment,maximum positive moments, maximum negative momentsand midspan deflection decrease by 11-50%, 38-76.4%, 38.6-76.8% and 14-39%, respectively due to this increasein the number of supports.

Reactive Powder Concrete can be considered as a special type of concrete in which the coarse aggregate will be eliminated to get a homogenous microstructure with a maximum density for the final result. Because of the importance of this type of concrete andits structural applications. This paper focused on reviewing the researchers that deal with the structural behavior of reactive powder concrete beams under bending load. Also, review the proposed design equations related to. reactive concrete behavior. Before starting a review of strength, stress-strain relation and ductility are presented because of their importance and effect on the structural behavior of beams under bending. According to the review of previous studies, the type of fibers and their content as a volumetric ratio, type of pozzolanic materials and its content, amount of longitudinal steel reinforcement are the main factors that affected the flexural behavior of reinforced Reactive Powder Concrete. For RPC the modulus of rupture has a significant positive effect on increasing steel fibers content. This positive effect reached 280% by using a steel fiber volumetric ratio of 2%, while the effect of increasing silica fume content from 5% to 15% has a limited effect on the modulus of rupture which increases it by only 7.8%. Based on test results for different studies one can conclude that quantity and type of fibers do not significantly affect cracking load but affected the rate of crack propagation, the failure loads, and stiffness. Also, it affects the failure mode from brittle failure to more ductile behavior.

The structural element within the whole structure contains structural elements like beams, slabs, columns and reinforced concrete walls. One of the most vertical structural elements is shear wall that built to giving stability to the building, resisting lateral force such as earthquake and wind and to reduce the building deformations. In present study, the analysis of corrugated vertical steel plate shear walls using finite element method by ABAQUS software is examined. Four different modes are analysed in which the first model is vertical corrugated steel shear wall plate, second is the composite shear wall with full interaction, third is the composite shear wall and finally the fourth model is composite shear wall with gap between concrete panel and steel frame to check out the full performance of different shear wall under the effects of cyclic loadings. Displacement, drift and energy dissipation will investigate throughout analysis. Analysis results indicated that the gap and composite action between steel and concrete panel play an important role on the performance of shear wall under cyclic loading. The decrease in displacement of composite shear wall as compared with the steel shear wall reach 11.86%

The compressive strength characteristics of mortar containing Ground Granulated Blast Furnace Slag (GGBFS) and Fly Ash (FA) in mortar by partial substitution of cement are investigated in this work. The increased demand for cement in the construction industry is a concern for environmental degradation; in this case, waste materials such as GGBFS and FA are used to replace cement. The optimal level of GGBFS and FA was determined using a percentage range of 0% to 40% for different curing days. Compressive strength tests were performed on the replaced mortar. For all mixes, the binder-to-water ratio was kept at 0.4. The compressive strength tests were conducted for 7, 28 and 90 days of curing on a Mortar. The result obtained that as the curing time increased the compressive strength of mortar containing GGBFS and FA increased. In comparison to M1 (cement only), the compressive strength improved by 13.15 percent and 15.5 percent at M3 (20%FA) and M8 (30%GGBFS), respectively. The results showed that adding GGBFS and FA to mortar improve compressive strength, which is improves the mechanical properties of the mortar.