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The Effective Width in Composite Steel Concrete Beams at Ultimate Loads
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A composite section is made up of a concrete slab attached to a steel beam by means of shear connectors. Under positive and negative bending moment, part of the slab will act as a flange of the beam, resisting the longitudinal compression or tension force. When the spacing between girders becomes large, it is evident that the simple beam theory does not strictly apply because the longitudinal stress in the flange will vary with distance from the girder web, the flange being more highly stressed over the web than in the extremities. This phenomenon is termed "shear lag". In this paper, a nonlinear three-dimensional finite element analysis is employed to evaluate and determine the actual effective slab width of the composite steel-concrete beams by using the
Analysis System computer program (ANSYS 11.0). The of elements were used (SOLID65, LINK8, SHELL143, COMBIN39, TARGE170 and
CONTA174) to model the concrete slab, the steel reinforcing bars, the steel girder, the shear connectors (including uplift and dowel action), and the interface between top flange of the steel girder and concrete slab, respectively. Comparisons with experimental tests have been performed to validate the finite element analysis results. In general, excellent agreement between the finite element solution and the experimental results has been obtained. The maximum difference in ultimate load is about (2.9%). Finally, parametric studies have been carried out to investigate the effect of some important parameters; these parameters include the degree of interaction, slab thickness, slab width, concrete compressive strength ( ), distribution of shear connectors, reinforcement of slab, type of loading, and boundary conditions. The effect of changing these parameters causes variety in the effective slab width and the maximum stress reaches 40.7% and 28.5%, respectively.

 

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Publication Date
Thu Nov 21 2019
Journal Name
Al-kindy College Medical Journal
Prevalence And Antimicrobial Susceptibility Patterns Of Bacteria Isolated From Urinary Tract Infections (UTIs) In Children At Children Hospital In Baghdad
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Background: First six to twelve months after initial urinary tract infection, most infections are caused by Escherichiacoli, although in the first year of life Klebsiella pneumoniae, Pseudomonas, Enterobacter spp andEnterococcus spp, are more frequent than later in life, and there is a higher risk of urosepsis compared with adulthood

Objectives: To determine the prevalence of bacterial isolates from Urinary Tract Infections of children at a children hospital in Baghdad and their antimicrobial susceptibility patterns.

Type of the study: Cross-sectional study.

Methods: During six months of study (1 June to 31 Dece

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Publication Date
Sat Dec 31 2016
Journal Name
Al-kindy College Medical Journal
Trends of Neonatal Mortality in context of Case Overload in Al - Alwyia Pediatric Teaching Hospital at Baghdad during 2005-2012
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Background: Data on the impact of neonatal and total pediatric admissions volume on neonatal mortality are sparse. Objectives: This study is done to estimate the neonatal mortality in relation to neonatal admissions and to total hospital admissions in Al-Alwyia Pediatric Teaching Hospital through years 2005-2012 Type of the study: A retrospective study.Methods: statistical records of all cases admitted to APTH were studied during 2005-2012.Results: Neonatal mortality decreased to the nadir at last year of study period (2012) and reached 6.1% of neonatal admissions compared to 2005 level which was 9.7 %. Mortality rate among premature and low birth weight (LBW) infants decreased also. The study also reveals that neonatal mortality constit

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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Developing strategic leadership practices in the light of transparency and organizational citizenship behavior - A field study of a sample of the staff of the Office of the Inspector General at the Iraqi Ministry of Culture
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Diversity the terms and practice the organizational filed with different concepts and environment, which Iraqi environment part from them. Some organizational in Iraqi environment leave its basic oriented to agreement with the leader desire, their fore this research focus tow basic variable (organizational citizenship behavior & transparence), we supposition which is dependent to explanation the response variable (strategic leadership). The results justification in part and not justification in another part. For example the organizational citizenship behavior effect on some parte of the strategic leadership. The transparence have faraway to fly from the relation with organizational citizenship behavior and strategic leadershi

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Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Some Properties of Polymer Modified Self-Compacting Concrete Exposed to Kerosene and Gas Oil
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This thesis aims to study the effect of addition polymer materials on mechanical properties of self-compacting concrete, and also to assess the influence of petroleum products (kerosene and gas oil) on mechanical properties of polymer modified self-compacting concrete (PMSCC) after different exposure periods of (30 ,60 ,90 ,and 180 days).

Two type of curing are used; 28 days in water for SCC and 2 days in water followed 26 days in air for PMSCC.

The test results show that the PMSCC (15% P/C ratio) which is exposed to oil products recorded a lower deterioration in compressive strength's values than reference concrete. The percentages of reduction in compressive strength values of PMSCC (15% P/C ratio) was

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Engineering
Non-Destructive Testing of Carbon Fiber Reinforced Magnetic Reactive Powder Concrete Containing Nano Silica
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This study involves the design of 24 mixtures of fiber reinforced magnetic reactive powder concrete containing nano Silica. Tap water has been used in mixing 12 of these mixtures, while the other 12 have been mixed using magnetic water. Nano Silica (NS) with ratios (1, 1.5, 2, 2.5 and 3) % were used. The results showed that the mixture containing 2.5%NS gives the highest compressive strength at age 7 days. Many different other tests were carried out, the results showed that the fiber reinforced magnetic reactive powder concrete containing 2.5% NS (FRMRPCCNS)  has the higher bulk density, dynamic modulus of elasticity, ultrasonic pulse velocity  electrical resistivity and lesser absorption than fiber reinforced

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Strengthening and Closing Cracks for Existing Reinforced Concrete Girders Using Externally Post-Tensioned Tendons
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This research is devoted to study the strengthening technique for the existing reinforced concrete beams using external post-tensioning. An analytical methodology is proposed to predict the value of the effective prestress force for the external tendons required to close cracks in existing beams. The external prestressing force required to close cracks in existing members is only a part from the total strengthening force.
A computer program created by Oukaili (1997) and developed by Alhawwassi (2008) to evaluate curvature and deflection for reinforced concrete beams or internally prestressed concrete beams is modified to evaluate the deflection and the stress of the external tendons for the externally strengthened beams using Matlab

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Quality Evaluation of Al-Rasheed Ready Concrete Mixture Plant By Using Six Sigma Approach
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The objective of this research work is to evaluate the quality of central concrete plant of Al-Rasheed Company by using Six Sigma approach which is a measure of quality that strives for near elimination of defects using the statistical methods to improve outputs that are critical to customers. The fundamental objective of Six Sigma methodology is the implementation of a measurement-based strategy that focuses on process improvement and variation reduction to reach delighting customers, and then suggesting an improvement system to improve the production of concrete in Al-Rasheed State Contracting Construction Company.
A field survey includes two parts (open and close questionnaire) that aimed to get the data and information required f

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Publication Date
Tue Mar 01 2016
Journal Name
Journal Of Engineering
Some Mechanical Properties of Concrete by using Manufactured Blended Cement with Grinded Local Rocks
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The  use  of  blended  cement  in  concrete  provides economic, energy savings,  and ecological  benefits, and also  provides. Improvement in the properties of materials incorporating blended cements. The  major  aim  of  this  investigation  is  to  develop  blended  cement  technology using  grinded local rocks . The research includes information on constituent materials, manufacturing processes and performance characteristics of blended cements made with replacement (10 and 20) % of grinded local rocks (limestone, quartzite and porcelinite) from cement.

The main conclusion of this study was that all ty

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Publication Date
Sun Jun 11 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evaluation of Mechanical Strength of Epoxy Polymer Concrete Reinforcement with Different Types of Fibers
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 Polymer composite materials were prepared by mixing epoxy resin with sand particles in three different grain size (150-300 ), (300-600 ) and (600- 1200) μm . The weight of epoxy was 15%, 20%, 25% and 30% of the total weight. Compression  strength and flexural strength tests were carried out for the prepared samples .The percentages of epoxy resin at 20% wt and 25% wt showed best mechanical properties for all grain sizes .These percentages were adopted to fill the void between particles sand which have two different size ranges (150-600) μm and {(150-300) & (600-1200)} μm respectively to obtain more dense material. The results showed that the strength of polymer composite at 20% resin is higher than 25% resin. The

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Publication Date
Wed Aug 28 2019
Journal Name
Journal Of Engineering
Influence of Liquid Asphalt on Resilient Modules and Permanent Deformation of Recycled Asphalt Concrete
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Tests were performed on Marshall samples and were implemented for permanent deformation and resilient modulus (Mr) under indirect tensile repeated loading (ITRL), with constant stress level. Two types of liquid asphalt (cutback and emulsion) were tried as recycling agents, aged materials that were reclaimed from field (100% RAP), samples were prepared from the aged mixture, and two types of liquid asphalt (cutback and emulsion) with a weight content of 0.5% were utilized to prepare a recycled mixture. A group of twelve samples was prepared for each mixture; six samples were tested directly for ITRL test (three samples at 25˚C and three samples at 40˚C), an average value for ITRL for every three samples was calculated (

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