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Effect of Construction Joints on Performance of Reinforced Concrete Beams
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Construction joints are stopping places in the process of placing concrete, and they are required because in many structures it is impractical to place concrete in one continuous operation. The amount of concrete that can be placed at one time is governed by the batching and mixing capacity and by the strength of the formwork. A good construction joint should provide adequate flexural and shear continuity through the interface.

In this study, the effect of location of construction joints on the performance of reinforced concrete structural elements is experimentally investigated.

Nineteen beam specimens with dimensions of 200×200×950 mm were tested. The variables investigated are the location of the construction joints (at midspan or at third point of the specimens), type of construction joints (vertical, inclined, and key construction joints), and presence of stirrups at these joints. The specimens were tested using 1000 kN computer controlled versatile electronic testing machine. The specimens were positioned in the machine so that the deflection at center and\or at the location of construction joint was measured at each load step.

The results of the experimental program indicated that the best location of the construction joint is at the point of minimum shear. It was found that the use of vertical construction joint has little effect on the overall behavior of beam specimens (the percentage of reduction in ultimate load capacity is in the range of 0% - 5%).

While inclined construction joints results in a noticeable reduction in strength of beams relative to the strength of beam without construction joint the percentage of reduction in ultimate load capacity is in range of 8% - 20%.The presence of stirrups at the construction joints is an important variable, which affect the type of failure and load carrying capacity. It is found that adding of stirrups across the joint results in an increase in capacity in the range of (7%- 15%) and a decrease in deflection in the range of (20%- 48%).

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Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Study of Mechanical Properties of (Al-Cu-Mg) Alloy Matrix Composite
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The present research had dealt with preparing  bars  with the length of about  (13 cm) and  adiametar  of  (1.5 cm) of composite materials with metal  matrix  represented by (Al-Cu-Mg) alloy cast enforced by (ZrO2) particles with chosen weight  percentages (1.5, 2.5 ,3.5, 5.5 %). The base  cast and the composite  materials were prepared by casting method by uses vortex  Technique inorder to  fix up (ZrO2) particles in homogeneous way on  the  base cast. In addition to  that, two main groups of composite materials were prepared depending on the particles size of (ZrO2) , respectively.       &n

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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
OIL OF IRAQ AND MULTI-NATIONALITIES COMPANIES "Geopolitical point of view"
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Multi-nationalities companies are the main companies in the progressed
countries that improve the current technology and, thus, become the main source of it.
These companies, in the first place, aim to increase the profits of its
investments to satisfy stock holders in the original countries to which these companies
belong.
It is a mean to interfere in the economic of countries especially the growing
ones and exploit their important natural resources. Since this research focus on the
dangers of these companies, mechanism of its work and its dangers on the most
important natural resources of our country which is oil; therefore, the research
confirm that this important natural treasure must be under an Iraqi cont

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Publication Date
Thu Mar 26 2009
Journal Name
Iraq Journal For Science
Calculation of time Entry and Exit of satellites from Earth Shadow
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The tracking of satellites motion and their path around the earth is important things in the mechanical of satellites motion. Significant parameters for the determination of time entrance and existence of the satellite could be obtained from the shadow of the earth. In the present work the tracking and time determination for entry and exit from earth shadow have been studied. In the present work we built a software for tracking the motion of satellites in orbit around the earth and determine the change of both distance and speed as a function of time. The perturbations effect on the satellite has been neglected from the earth atmosphere drag and the earth gravity and other effects. The equation for calculating the shadow is solved using num

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Publication Date
Tue Jan 01 2019
Journal Name
Aip Conference Proceedings
Improvement of electrical features of SnO2 based varistor doped with Al2O3
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One of the important objectives of the varistor is for a sustainable environment and reduce the pollution resulting from the frequent damage of the electrical devices and power station waste. In present work, the influence of Al2O3 additives on the non –linear electrical features of SnO2 varistors, has been investigated, where SnO2 ceramic powder doped with Al2O3 in three rates (0.005, 0.01, and 0.05), the XRD test improved that SnO2 is the primary phase, while CoCr2O4, and Al2O3 represent the secondary phases. The electrical tests of all prepared samples confirmed that the increasing of Al2O3 rates and sintering temperature improves and increase the electrical features, where the best results obtained at Al2O3 (0.05) and 1000℃, the non

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Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Improvement of the technique for the solution method of Gauss Seidel
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In this paper, a new approach was suggested to the method of Gauss Seidel through the controlling of equations installation before the beginning of the method in the traditional way. New structure of equations occur after the diagnosis of the variable that causes the fluctuation and the slow extract of the results, then eradicating this variable. This procedure leads to a higher accuracy and less number of steps than the old method. By using the this proposed method, there will be a possibility of solving many of divergent values equations which cannot be solved by the old style.

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Publication Date
Mon Sep 30 2024
Journal Name
Malaysian Journal Of Science
DEVELOPMENT OF A SPECTROPHOTOMETRIC DETERMINATION OF PREDNISOLONE IN DIFFERENT DOSAGE FORMS
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A sensitive, accurate, and affordable colorimetric method was developed for assaying prednisolone (PRZ) in various medicinal forms. The procedure involves the oxidation of PRZ by ferric ions, followed by complexation of the resulting ferrous ions with ferricyanide to produce a greenish-blue product. Common complexation conditions were thoroughly investigated. The mole ratio of FeCl₃·6H₂O to K₃Fe(CN)₆ was 8:1. The proposed mechanism of complexation was suggested and considered. Various parameters were optimized, including the reduction of the colorimetric reaction temperature to 50°C and the duration of heating and analysis to 20-30 minutes. The calibration curve was linear over the range of 1-60 µg/mL. The limit of detection (LOD

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Publication Date
Tue Feb 05 2019
Journal Name
Journal Of The College Of Education For Women
Biography of the Last The formation of the ancient Pharaonic Warrior
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Cash studies on Biography few self, compared to what feet of analysis and criticism in the other arts as (novel, short story, poetry, theater, painting), however, is a biographical articles in the relatively few Arabic literature as presented in the other Arts, has taken this Art greater opportunity in our literature with his Taha Hussein (days), or (my life) to Ahmed Amin, or Fadwa Toukan (a nice trip, and difficult journey), or Jabra Ibrahim Jabra in the (first well) or (Princess Street), which forms taken from the self point of departure the desire to write a CV to try to familiarize readers with the information possible to the same creator, the remainder (ego) is the axis basis in a CV, gradually, starting from childhood through yout

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Publication Date
Wed Jan 01 2020
Journal Name
Route Educational And Social Science Journal
SURVIVAL IN TIMES OF PANDEMICS: THE PROPHETIC VISION OF JACK LONDON
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Publication Date
Sun Jan 01 2023
Journal Name
Iraqi Journal Of Applied Physics
Fabrication and Improvement of Optoelectronic Properties of Copper Chalcogenide Thin Films
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Scopus (1)
Scopus
Publication Date
Wed Sep 02 2015
Journal Name
Lap Lambert Academic Publishing
The role of tibialis posterior transfer in correction of foot drop
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