The present work is concerned with the investigation of the behavior and ultimate capacity of axially loaded reinforced concrete columns in presence of transverse openings under axial load plus uniaxial bending. The experimental program includes testing of twenty reinforced concrete columns (150 × 150 × 700 mm) under concentric and eccentric load. Parameters considered include opening size, load eccentricity and influence of the direction of load eccentricity with respect to the longitudinal axis of the opening. Experimental results are discussed based on load – lateral mid height deflection curves, load – longitudinal shortening behavior, ultimate load and failure modes. It is found that when the direction of load
... Show MoreUndoubtedly, rutting in asphalt concrete pavement is considered a major dilemma in terms of pavement performance and safety faced by road users as well as the road authorities. Rutting is a bowl-shaped depression in the wheel paths that develop gradually with the increasing number of load applications. Heavy axle loadings besides the high pavement summer temperature enhance the problem of rutting. According to the AASHTO design equation for flexible pavements, a 1.1 in rut depth will reduce the present serviceability index of relatively new pavement, having no other distress, from 4.2 to 2.5. With this amount of drop in serviceability, the entire life of the pavement in effect has been lost. Therefore, it is crucial to look at the mechani
... Show MoreFrequently, Load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some sections poorly drained are the main failure types found in some of the newly constructed road within Baghdad as well as other cities in Iraq. The use of hydrated lime in pavement construction could be one of the possible steps taken in the direction of improving pavement performance and meeting the required standards. In this study, the mechanistic properties of asphalt concrete mixes modified with hydrated lime as a partial replacement of limestone dust mineral filler were evaluated. Seven replacement rates were used; 0, 0.5, 1, 1.5, 2, 2.5 and 3 percent by weight of aggregate. Asphalt concrete mixes were prepared at their
... Show MoreThis article investigates the development of the following material properties of concrete with time: compressive strength, tensile strength, modulus of elasticity, and fracture energy. These properties were determined at seven different hydration ages (18 h, 30 h, 48 h, 72 h, 7 days, 14 days, 28 days) for four pure cement concrete mixes totaling 336 specimens tested throughout the study. Experimental data obtained were used to assess the relationship of the above properties with the concrete compressive strength and how these relationships are affected with age. Further, this study investigates prediction models available in literature and recommendations are made for models that are found suitable for application to early age conc
... Show MoreUsing fiber-reinforced polymer (FRP) could effectively improve the strength and endurance of reinforced concrete (RC) constructions. This study evaluated the flexural behavior of one-way concrete slabs with openings reinforced with glass fiber-reinforced polymers (GFRP) bars. It strengthened using carbon fiber-reinforced polymer (CFRP) sheets around the openings. The experimental program of this study is adopted by casting and testing four one-way concrete slabs with dimensions of (150*750*2650) mm. These slabs are divided into two groups based on whether they were strengthened or un-strengthened. For each group, two different openings (either one rectangular or two square) measured 250*500 mm and 250*250 mm, respective
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The aim of the research is to identify the effect of using the self-questioning strategy on the achievement of fourth-grade students in science and the development of their reflective thinking in physics in the city of Baghdad. The research sample was divided into two groups: an experimental group of (20) students and a control group of (20) students. The researchers developed two tools: a test of (40) multiple-choice questions. The second tool is a test to measure the reflective thinking skills of fourth-grade students. It consists of (25) multiple-choice questions distributed on skills as follow: reflection and observation, detection of inaccuracies, reaching conclusions, giving clear explanations, an
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The current research aims to identify the effect of the idea filtering strategy on the achievement of second-intermediate school female students in science. The two researchers adopted the experimental method and the experimental design with partial control in the two groups (experimental group and control group). The two researchers applied the research experience to a sample of students of the second intermediate grade in the school Martyrs of (Jiser Al Aimma for Girls) affiliated with the Baghdad Education Directorate / Rusafa /1 for the academic year (2021/2022), which was chosen intentionally. The number of female students in the research sample was (70) students, with (35) students for the ex
... Show MoreScientific research on the environment of the Iraqi marshes, its beauty and its characteristics is considered one of the most important functions of Iraqi universities and scientific institutions, because of its great historical impact related to the identity of Iraq and the Iraqis and the basis of science and science, through which the first letter and the first human civilizations were established and in the same importance technical research is among the most important functions of departments Institutes and colleges of the arts, research centers and museums inside and outside Iraq. Also, research centers specialized in the natural environment of Iraq, including the marshes. Therefore, it is hoped that this research will develop the a
... Show MoreThe effectiveness and quality of legislation depend on the extent to which it relates to political , economic ,social ,geographical , health and moral realities , so the unrealistic legislation and its failure to address all the problems facing society make these legislation out of reality , this requires this legislation be able to regulate all aspects related to public health in society in exceptional circumstances such as cases of wars ,diseases and pandemics as outbreaks of corona virus in the word ,this study focuses on the effects of legislative omission on the effectiveness of the administration when performing its tasked in health administrative control in exceptional circumstances in light of spread of corona virus pandemic in Iraq
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