This study reports testing results of the transient response of T-shape concrete deep beams with large openings due to impact loading. Seven concrete deep beams with openings including two ordinary reinforced, four partially prestressed, and one solid ordinary reinforced as a reference beam were fabricated and tested. The effects of prestressing strand position and the intensity of the impact force were investigated. Two values for the opening’s depth relative to the beam cross-section dimensions were inspected under the effect of an impacting mass repeatedly dropped from different heights. The study revealed that the beam’s transient deflection was increased by about 50% with greater amplitudes for response oscillations due to impact loading as the impact force increased twice. The results showed that the transient strains in the reinforcement and concrete increased when increasing the opening depth with higher amplitudes for the response oscillations, whereas it had a minimal effect on the beam’s transient deflection. The reinforcement and concrete strain results indicated a higher damping for the strains as the prestressing strands were introduced. Comparison with solid deep beam response showed remarkable increase in the beam deflection and strains with greater amplitudes for response oscillations when large openings were introduced in the web.
The research objective was to study the amount of lost fluids, some blood components and mineral salts in volleyball players under hot weather conditions. The sample of the present study was composed of 12 volleyball players of Al-Sinaa Club (Baghdad, Iraq) in the 2022/2023 season. The variables analyzed in this study were: Heart rate before and after exercise, internal and external body temperature before and after exertion, potassium ion, sodium ion, calcium ion, and the amount of fluid lost (the player's weight) before and after the exercise. The tests were conducted at a temperature between 42-47 degrees Celsius. The maximum anaerobic exercise was performed with volleyball. The results showed that to play volleybal
... Show MoreHydrogen and nanocarbon were produced by the catalytic decomposition of electrocracking gas obtained by the pyrolysis of liquid organic waste via electric arc discharge. The GIAP-16 (NiO-Al2O3) industrial catalyst was used to reduce the maximum decomposition temperature to 700 °C. In a fixed-bed reactor, under atmospheric pressure, reasonable amounts of high-purity hydrogen were produced, accompanied by deposits of nanocarbon by-product. The NiO-Al2O3 catalyst showed excellent catalytic activity. X-ray powder diffraction analysis of the NiO-Al2O3 composite revealed the presence of cubic NiO and rhombohedral Al2O3, which were chemically stable. However, above 500 °C, NiAl2O4 began to appear. The specific surface area of the catalyst was de
... Show MoreIn this experimental and numerical analysis, three varieties of under-reamed piles comprising one bulb were used. The location of the bulb changes from pile to pile, as it is found at the bottom, center, and top of the pile, respectively.
The research objective was to study the amount of lost fluids, some blood components and mineral salts in volleyball players under hot weather conditions. The sample of the present study was composed of 12 volleyball players of Al-Sinaa Club (Baghdad, Iraq) in the 2022/2023 season. The variables analyzed in this study were: Heart rate before and after exercise, internal and external body temperature before and after exertion, potassium ion, sodium ion, calcium ion, and the amount of fluid lost (the player's weight) before and after the exercise. The tests were conducted at a temperature between 42-47 degrees Celsius. The maximum anaerobic exercise was performed with volleyball. The results showed that to play volleybal
... Show MoreDue to the numerous motor and performance skills required of female students in futsal refereeing during college lessons, along with the constant need to reposition themselves and move within the playing field, continuous monitoring and repetition are essential to minimize potential errors during performance. These errors may arise from failing to assume the correct position or delays in signalling officiating gestures. Addressing this issue necessitated the implementation of an electronic program and supplementary tools—such as electronic games, scientific posters illustrating officiating signals, and other instructional aids—since these serve as guiding tools that direct individuals toward correct performance by distinguishing
... Show MoreIn this paper, Nordhaus-Gaddum type relations on open support independence number of some derived graphs of path related graphs under addition and multiplication are studied.
As computers become part of our everyday life, more and more people are experiencing a
variety of ocular symptoms related to computer use. These include eyestrain, tired eyes, irritation,
redness, blurred vision, and double vision, collectively referred to as computer vision syndrome.
The effect of CVS to the body such as back and shoulder pain, wrist problem and neck pain.
Many risk factors are identified in this paper.
Primary prevention strategies have largely been confined to addressing environmental
exposure to ergonomic risk factors, since to date, no clear cause for this work-related neck pain
has been acknowledged. Today, millions of children use computers on a daily basis. Extensive
viewing of the compute
In this paper, the behavior of structural concrete linear bar members was studied using numerical model implemented in a computer program written in MATLAB. The numerical model is based on the modified version of the procedure developed by Oukaili. The model is based on real stress-strain diagrams of concrete and steel and their secant modulus of elasticity at different loading stages. The behavior presented by normal force-axial strain and bending moment-curvature relationships is studied by calculating the secant sectional stiffness of the member. Based on secant methods, this methodology can be easily implemented using an iterative procedure to solve non-linear equations. A compari
Experimental research was carried out to investigate the performance of CFRP wrapping jackets used for retrofitting twelve square reinforced concrete (CR) column specimens damaged by exposure to fire flame, at different temperatures of 300, 500 and 700ºC, except for two specimens that were not burned. The specimens were then loaded axially till failure after gradual or sudden cooling. The specimens were divided into two groups containing two main reinforcement ratios, ρ= 0.0314 and ρ= 0.0542. This was followed by the retrofitting procedure that included wrapping all the specimens with two layers of CFRP fabric sheets. The test results of the retrofitted specimens showed that the fire damaged RC
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