Ali Fadhil Naser
Volume 10, Issue 3 , September 2017, Pages 244-258
Abstract
The aim of this study is to select the suitable shape of girder cross section that is used in the design of bridges structure, and to evaluate the effect of cross section shape of bridges girders on the static properties such as vertical displacement, vertical shear force, bending moment, tension stress ...
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The aim of this study is to select the suitable shape of girder cross section that is used in the design of bridges structure, and to evaluate the effect of cross section shape of bridges girders on the static properties such as vertical displacement, vertical shear force, bending moment, tension stress and compressive stresses.
Ten bridges models using different types and shapes of girders were used to study the effect of girder cross section shape in the construction of bridges by adopting static analysis.
The results of finite element analysis showed that the bridges models of separated concrete deck over girders have higher value of vertical displacement, positive bending moment, and tensile stress. These models are not suitable for design of bridges that subjected to higher traffic loads because of these bridges structures will not have enough stiffness and higher carrying capacity. Therefore, they will fail under heavy traffic loads. These models include flat slab bridge model, T-girder bridge model, I-girder bridge model, and steel I-girder bridge model. Most box girders bridge models appeared the lower values of vertical displacement, positive bending moment, and tensile stress. Therefore, these models will have enough stiffness and carrying capacity and they will be more elasticity from others models.
This study recommended that using the box girders bridges models in the construction of new bridges structure that have high traffic loads.
Baha S. Mahdi; Neam Fawzi Mohammed
Volume 10, Issue 3 , September 2017, Pages 259-273
Abstract
The aim of this work is to study the effect of filler metal alloy, on the metallurgical aspects of diffusion rate and mechanical properties of the brazing joint using two types of Silicon-Aluminum filler metal alloys on the commercially aluminum base metal. The brazing process experiments done by joining ...
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The aim of this work is to study the effect of filler metal alloy, on the metallurgical aspects of diffusion rate and mechanical properties of the brazing joint using two types of Silicon-Aluminum filler metal alloys on the commercially aluminum base metal. The brazing process experiments done by joining Al-alloys (1100) type by a brazing process using (AlSi5,AlSi12) filler metals at 600-650oC. Two types of joint were made, inclined and curvature design. To indicate the brazing joint performance the specimens tested for single shear tensile test and metallurgical testing using optical and scanning electron microscope attached with energy dispersive detector. Diffusion rate results according to joint clearance and brazing time accomplished using optical microscope images for joints cross sections and data gained with assisting of ImageJ® software. The joint sections analyzed using EDS detector and X-Ray analysis to observe the produced phases. The major phases of brazed joints using 12%Si filler alloy gives (Al, Fe3Si, Al 0.3Fe3Si0.7) and (Al 0.3Fe3Si0.7) for the 5%Si filler alloy. The two filler alloys (5 and 12%Si) had equivalent tensile strength with respect to the base metal (Al-1100 alloy) of 176 and 128MPa respectively, therefore the maximum joint efficiencies are 170% for AL5%Si filler alloy and 123% for AL12%Si filler alloy which mean that the tensile strength of the brazed joint had values greater than 100%.
Inaam Ibrahim ALI
Volume 10, Issue 3 , September 2017, Pages 274-290
Abstract
This paper proposed an algorithm to find the best location of shunt capacitor and size to reduce the total active power loss and harmonics consideration after assuming electric arc furnace (EAF) in the unbalanced radial distribution network. Demonstrated the results by using practical software (CYMDIST) ...
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This paper proposed an algorithm to find the best location of shunt capacitor and size to reduce the total active power loss and harmonics consideration after assuming electric arc furnace (EAF) in the unbalanced radial distribution network. Demonstrated the results by using practical software (CYMDIST) as a tool, to determine power flow and find the best capacitors size and location that decrease power loss and improve voltage profile. The total harmonic voltage distortion at system does not exceed the maximum allowable total harmonic voltage distortion level (THVD%) compared with IEEE-standard 519-1992. To attain the goal of this algorithm, these algorithms are tested in 25-buses un-balanced radial distribution system and an actual part of Baghdad city distribution network that is content 66-bus for Al_JIHAD_feeder_5 11 kV network are depicted for the implementation of this analysis.
Zaid Ali Kadhim Alzaidi
Volume 10, Issue 3 , September 2017, Pages 291-298
Abstract
In this study, composite columns have been tested under axial load. The steel tubes were filled with waste concrete to perform the composite action. The specimens divided into two groups; square and circular columns. The diameter of the circular hallow columns was 7.5 cm with 2mm thickness, while the ...
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In this study, composite columns have been tested under axial load. The steel tubes were filled with waste concrete to perform the composite action. The specimens divided into two groups; square and circular columns. The diameter of the circular hallow columns was 7.5 cm with 2mm thickness, while the dimension of the square hallow columns was (7.5 cm × 7.5 cm) with 2mm thickness. For each group a column without waste concrete filled steel tubular (W.C.F.S.T) was tested to act as a reference column. Load-deflection curves were constructed for all specimens. The results indicate that the waste concrete filled steel tube has more capacity due to the composite action. The pattern of failure in circular sections was different from the failure pattern of the square ones.
Dhia Badr Ghailan
Volume 10, Issue 3 , September 2017, Pages 299-307
Abstract
In this work the concrete free falling effect on segregation was investigated. Sixteen free falling specimens were tested by the non-destructive ultrasonic test for four types of concrete. In addition, twelve cube specimens were tested to check the accuracy of the ultrasonic test adopted in this study. ...
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In this work the concrete free falling effect on segregation was investigated. Sixteen free falling specimens were tested by the non-destructive ultrasonic test for four types of concrete. In addition, twelve cube specimens were tested to check the accuracy of the ultrasonic test adopted in this study. Four types of aggregates (rounded gravel, crushed gravel, 10mm maximum size crushed gravel and porcelain aggregate) were used to study their effect on segregation of free falling concrete from different height. The test results show that no significant effect for the free falling on the compressive strength of concrete for the four types of aggregate and the results of the non-destructive ultrasonic test were of good agreement with those of compression machine test.
Labeeb S. Al-Yassri; Ammar Y. Ali; Mohammed M. AL-Khafaji
Volume 10, Issue 3 , September 2017, Pages 308-317
Abstract
This paper provides an experimental study to investigate the effect of hybrid reinforcement on the behavior of hollow core slab casted with NSC. Experimental results showed that using of hybrid reinforcement (CFRP and steel bars) as internal reinforcement give better results of ductility compared with ...
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This paper provides an experimental study to investigate the effect of hybrid reinforcement on the behavior of hollow core slab casted with NSC. Experimental results showed that using of hybrid reinforcement (CFRP and steel bars) as internal reinforcement give better results of ductility compared with HCS reinforced with CFRP bars only. On the other hand, using of CFRP bars as an internal reinforcement have slightly effect on the shear strength capacity of hollow core slab. On the other hand, CFRP reinforcement lead to decrease the stiffness of slab at post cracking stage; therefore, deflection will increase at the same load after cracking.
Angham E. Ali Al-Saffar; Ahmed Zghair Jaber Al-Joboury
Volume 10, Issue 3 , September 2017, Pages 318-337
Abstract
This study is concerning in recognizing and defining the factors affected on water resources in Iraq, by application of knowledge discovery in database (KDD) techniques, KDD is a useful technique to discover the underlying concepts and unusual knowledge and that were not previously known from databases ...
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This study is concerning in recognizing and defining the factors affected on water resources in Iraq, by application of knowledge discovery in database (KDD) techniques, KDD is a useful technique to discover the underlying concepts and unusual knowledge and that were not previously known from databases through a systematic process. There are lot software package usages with (KDD), while in this paper (Microsoft Excel) was used, since it is availableness and Easygoingness. Many factors are detected which have an impact on water resources in Iraq. External factors have not controlled by Iraq management such as water policies of riparian countries and climate factors (natural) while internal factors are under Iraqi control such as irrigation methods and losses. Some of these factors affected on quantity or quality or both. Finally a successive management shall take care all these factors.
Alaa M. A. Al-Khekany; Haitham H. Muteb
Volume 10, Issue 3 , September 2017, Pages 338-351
Abstract
In general, the reinforced concrete slab in composite unsymmetrical steel plate girder contributes in increased the ultimate strength of composite section under combined effect of bending and torsion moments. The contribution value of slab in composite section is unknown, so this study is adopted. Six ...
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In general, the reinforced concrete slab in composite unsymmetrical steel plate girder contributes in increased the ultimate strength of composite section under combined effect of bending and torsion moments. The contribution value of slab in composite section is unknown, so this study is adopted. Six specimens were either non-composite or composite reinforced concrete slab and with symmetrical/unsymmetrical steel plate girders were adopted in this study. The specimens were divided into three non-composite steel plate girders and the others were composite with RC slab. The specimens were tested under effect of combined bending and torsion moments.
The general behavior and response of the tested specimens were recorded and discussed in this paper. For each tested plate girder, the ultimate strength, load at cracking, failure's mode, and load/deflection relationship at mid-span and under points load were gaged. The experimental results show that the concrete slab contributes in increasing the ultimate load of composite section by a ratio (53.85)% for symmetrical section and (155.63 – 242.51)% for unsymmetrical section when the composite girder under loaded out of supported plane, and the contribution value of concrete slab in composite plate girder increased in unsymmetrical section than symmetrical section this is due to the ideal use of materials.
Mohammed Ail Mutar; NOOR MOHAMMED ABDUL HASSAN
Volume 10, Issue 3 , September 2017, Pages 352-367
Abstract
Alkyd resins constitute a very high proportion of conventional binders used in surface coating . A new alkyd resins were synthesized by reacting ( Bitter almond oil or Coconut oil with propylene glycol or Ethylene glycol and phthalic anhydride) in the presence of lead oxide as a catalyst. synthesis of ...
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Alkyd resins constitute a very high proportion of conventional binders used in surface coating . A new alkyd resins were synthesized by reacting ( Bitter almond oil or Coconut oil with propylene glycol or Ethylene glycol and phthalic anhydride) in the presence of lead oxide as a catalyst. synthesis of alkyd resins, two stages were involved. At the first stage, Bitter almond oil or Coconut oil was converted to monoglycerides as a polyol by alcoholysis. Esterification process was held at the second stage by adding phthalic anhydride and xylene in the mixture. Three different alkyd resins have been synthesized (Short , medium and long) from Bitter almond oil or Coconut oil by using different ratios of phthalic anhydride .The various physic-chemical properties of alkyd resins like acid value , saponification value , iodine value Density, viscosity, chemical resistance and volatile matter were studied . The resulted alkyd resins are readily soluble in aprotic polar solvents , such as (Toluene , Acetone , Benzene , xylene , DMF, DMSO , Methanol and ethanol ) without need for heating. Thermal analysis of alkyd resins by Thermo Gravimetric Analysis (TGA) and thermal differential calorimeter (DSC) techniques. reveals that these Aromatic alkyd resins possess thermal stability. Alkyd resins were characterized by (FTIR and 1H-NMR) spectroscopies .
