Industrial buildings usually are designed to sustain several types of load systems, such as dead, live, and dynamic loads (especially the harmonic load produced by rotary motors). In general, these buildings require high-strength structural elements to carry the applied loads. Moreover, Reactive Powder Concrete (RPC) has been used for this purpose because of its excellent mechanical strength and endurance. Therefore, this study provides an experimental analysis of the structural behaviors of reinforced RPC beams under harmonic loads. The experimental program consisted of testing six simply supported RPC beams with lengths of 1500 mm, widths of 150 mm, and thicknesses of 200 mm under harmonic loading with varied frequencies between 10 and 20 Hz. Different steel fiber ratios of 0%, 0.5%, 0.75%, 1.0%, 1.5%, and 1.75% were provided in the concrete mixes to explore the effect of steel fibers on the dynamic behavior of these beams. Except for the steel fiber volume fraction, all of the examined specimens shared the same material attributes and reinforcing details. The outcomes proved the positive effect of adding steel fibers on the dynamic response under the effect of harmonic loading. The optimum volume fraction of steel fibers was characterized by a percentage of 1.5%. Moreover, the vibration amplitude was more affected by the steel fibers than the support reactions. The inertial force increased as the harmonic loading duration increased. This increase in the inertial force by the load duration was enhanced after adding the steel fibers. However, this enhancement started to decline after increasing the steel fiber content to 1.75%.
UV-Vis technique has been used to study the adsorption of para-nitroaniline (PNA) on Iraqi siliceous rocks powder. Adsorption isotherms were investigated, temperature effect on adsorption was calculated, Results showed that the adsorption was an exothermic process and the thermodynamic functions were calculated. The effect of the pH on adsorption was studied and the ionic strength effect on adsorption was studied, It was found that adsorption increases with the presence of sodium chloride ions. The kinetic study of adsorption before equilibrium showed that the adsorption was pseudo first order according to according (Lagergren equation).
Recently, the application of geosynthetics in the reinforcement of weak subgrade is expanded dramatically. However, selection of the geo-material that fits site conditions and soil type is crucial to achieving the success of the overall performance of such improvement. Also, the road life and cost construction are significant keys for evaluating this type of ground treatment. This paper presents an overview of the subgrade strengthening with geosynthetics to acquire a better understanding of the technique and to provide a clear guide for transportation and geotechnical engineers. The rutting failure along with its main causes are highlighted briefly. The types of geosynthetics, their applications and
Crime is considered as an unlawful activity of all kinds and it is punished by law. Crimes have an impact on a society's quality of life and economic development. With a large rise in crime globally, there is a necessity to analyze crime data to bring down the rate of crime. This encourages the police and people to occupy the required measures and more effectively restricting the crimes. The purpose of this research is to develop predictive models that can aid in crime pattern analysis and thus support the Boston department's crime prevention efforts. The geographical location factor has been adopted in our model, and this is due to its being an influential factor in several situations, whether it is traveling to a specific area or livin
... Show MoreWind energy is considered one of the most important sources of renewable energy in the world, because it contributes to reducing the negative effects on the environment. The most important types of wind turbines are horizontal and vertical axis wind turbines. This work presents the full details of design for vertical axis wind turbine (VAWT) and how to find the optimal values of necessary factors. Additionally, the results shed light on the efficiency and performance of the VAWT under different working conditions. It was taken into consideration the variety of surrounding environmental conditions (such as density and viscosity of fluid, number of elements of the blade, etc.) to simulate the working of vertical wind turbines under di
... Show MoreAn investigation was conducted for the study of extraction of metal ions using aqueous biphasic systems. The extraction of iron, zinc and copper from aqueous sulphate media at different kinds of extractants SCN− , Cl- and I- , different values of pH of the feed solution, phase ratio, concentration of metals, concentration of extractant, concentration of polymer, and concentration of salt was investigated. Atomic absorption spectrophotometer was used to measure the concentration of iron, zinc and copper in the aqueous phase throughout the experiments. The results of the extraction experiments showed the use of SCN− as extractant, pH=2.5, phase ratio=1.5, concentration of metals 1g/l, concentration of extractant 0.06 %, concentration o
... Show MoreAeroelastic flutter in aircraft mechanisms is unavoidable, essentially in the wing and control surface. In this work a three degree-of-freedom aeroelastic wing section with trailing edge flap is modeled numerically and theoretically. FLUENT code based on the steady finite volume is used for the prediction of the steady aerodynamic characteristics (lift, drag, pitching moment, velocity, and pressure distribution) as well as the Duhamel formulation is used to model the aerodynamic loads theoretically. The system response (pitch, flap pitch and plunge) was determined by integration the governing equations using MATLAB with a standard Runge–Kutta algorithm in conjunction with Henon’s method. The results are compared with
... Show MoreThis essay aims to highlight the most important issues and difficulties facing implementing large projects that follow the turn-key method, considered one of the types of contractual methods in Iraq, especially for large and complex projects requiring speedy completion. The projects implemented in this way face delays and delays in completion, which led to the lack of benefit from the projects for which they were implemented, especially those affecting the lives of citizens within the health sector. The case study dealt with the construction of hospitals with multi-bed capacities within multiple governorates in Iraq, With large financial allocations within the federal budget of the Government of Iraq over several years.
... Show MoreThe present study aims at answering the following questions:.
1-Which is more effective in enriching students. Vocabulary ,the use of short stories or the traditional way?
2-What extent has the use of short stories an effect upon the students. achievement in vocabulary test?
3- Is there any significant difference between the male and female student of the experimental group in vocabulary achievement test?
 
... Show MoreThis work aims to provide a statistical analysis of metal removal during the Magnetic Abrasive Finishing process (MAF) and find out the mathematical model which describes the relationship between the process parameters and metal removal, also estimate the impact of the parameters on metal removal. In this study, the single point incremental forming was used to form the truncated cone made of low carbon steel (1008-AISI) based on the Z-level tool path. Then the finishing was accomplished using a magnetic abrasive process based on the Box-Behnken design of the experiment using Minitab 17 software was used to finish the surface of the formed truncated cone. The influences of different parameters (feed rate, machining step s
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