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Synthetic Sacks as Reinforced Fibers in the Thermosetting Composites
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This study was carried out to investigate the preparation of thermosetting polymeric blend consisting of three adhesive types, namely: epoxy, polyvinyl formal (PVF) and unsaturated polyester. Both of epoxy and PVF were used as a matrix-binder at fixed weight. Whilst unsaturated polyester was used at different weights and added to the matrix so as to produce prepared epoxy-PVF-unsaturated polyester blend. Several experiments were performed at different operating conditions, mixing speed and time at room temperature to identify the most favorable operating conditions. The optimum mixing speed and mixing time for the prepared blend were 500rpm and 5 minutes respectively.

      Solid wastes-synthetic sack fibers from high volume, low cost, renewable fiber sources have been used as environmentally friendly alternatives to reinforcing fibers in composites. Many mechanical and thermal tests were carried out of the prepared blend at different weighted ratios. The optimum weighted ratio of the prepared blend for the untreated samples was characterized by the hardness and bending deflection properties and it was 0.40w/w, while for impact strength and thermal conductivity properties was 0.20w/w respectively. At these optimum weighted ratios of untreated samples with sack fibers, the maximum values of hardness and impact strength properties were 95 shore and 2.25J/cm2 respectively. On the other hand, the minimum bending deflection and thermal conductivity properties values were found to be 4mm and 0.01094W/cm.oC respectively. They showed the best bonding forces and physical interaction between two concentrations of matrix and unsaturated polyester adhesives.

      Treated samples of sack fibers reinforced composites at their optimum weighted ratio showed better fiber-matrix interaction as observed from the experimental results leading to enhance and improve the mechanical (hardness, impact strength, and bending deflection) and thermal (thermal conductivity) properties when compared to the untreated sample. These improvements in treated samples with two layers of sack fibers were predominant.

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Publication Date
Fri Jun 30 2006
Journal Name
Tikrit Journal Of Engineering Sciences
Curvature Ductility of Reinforced Concrete Column Sections Under Different strain Rates
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This paper presents theoretical parametric study of the curvature ductility capacity for reinforced concrete column sections. The study considers the behavior of concrete and reinforcing steel under different strain rates. A computer program has been written to compute the curvature ductility taking into account the spalling in concrete cover. Strain rate sensitive constitutive models of steel and concrete were used for predicting the moment-curvature relationship of reinforced concrete columns at different rate of straining. The study parameters are the yield strength of main reinforcement, yield strength of transverse reinforcement, compressive strength of concrete, spacing of ties and the axial load. The results indicated that hi

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Publication Date
Fri Mar 01 2024
Journal Name
Advances In Structural Engineering
Simulation and design model for reinforced concrete slabs with lacing systems
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Lacing reinforcement plays a critical role in the design and performance of reinforced concrete (RC) slabs by distributing the applied loads more evenly across the slab, ensuring that no specific area of the slab is overloaded. In this study, nine slabs, divided into three groups according to the investigated parameters, were meticulously designed and evaluated to study the interplay between the lacing reinforcement and other key parameters. Each slab was crafted for simple support and was subjected to both static and repeated two-point load tests. The lacing reinforcement had an angle of 45° with various tension and lacing steel. The repeated-tested specimens with lacing reinforcement experienced smaller ductility than those of s

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Publication Date
Wed Mar 01 2023
Journal Name
Al-khwarizmi Engineering Journal
Mechanical PropertiesInvestigation of Unidirectional Woven Carbon Fiber Reinforced Epoxy Matrix Composite
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In this study, the mechanical properties of an epoxy and unidirectional woven carbon with fiberglass composite were experimentally investigated. When preparing the composite samples, American Society for Testing and Materials (ASTM)standard was used. Tensile, impact and flexural test were conducted to investigate the mechanical properties of the new produced epoxy Unidirectional Woven Carbon and Epoxy Fiberglass composites. The outcome showed that the strength of the produced samples increased with the increase in the number of unidirectional woven carbon layers added. Two methods were utilized: (1) woven carbon composite with glass fiber (2) woven carbon composite). The two methods of composite were compared with each other.  The resul

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Publication Date
Mon Dec 18 2017
Journal Name
Al-khwarizmi Engineering Journal
Fabrication of Carbon Nanotube Reinforced Al2O3/Cr2O3 Nanocomposites by Coprecipitation Process
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In this research, the effect of multi-walled carbon nanotubes (MWCNTs) on the alumina/chromia (Al2O3/Cr2O3) nanocomposites has been investigated. Al2O3/Cr2O3-MWCNTs nanocomposites with variable contents of Cr2O3 and MWCNTs were fabricated using coprecipitation process and followed by spark plasma sintering. XRD analysis revealed a good crystallinity of sintered nanocomposites samples and there was only one phase presence of Al2O3-Cr2O3 solid solution. Density, Vickers microhardness, fracture toughness and fracture strength have been measured in the sintered samples. The results show tha

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Publication Date
Sat Jan 01 2022
Journal Name
Journal Of The Mechanical Behavior Of Materials
Analysis of concrete beams reinforced by GFRP bars with varying parameters
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Abstract<p>Structural buildings consist of concrete and steel, and these buildings have confronted many challenges from various aggressive environments against the materials manufactured from them. It contains high water levels and buildings whose concrete cover may be damaged and thus lead to the deterioration and corrosion of steel. It was important to have an alternative to steel, such as the glass fiber reinforced polymer (GFRP), which is distinguished by its great effectiveness in resisting corrosion, as well as its strong tensile resistance. Still, one of its drawbacks is that it has a low modulus of elasticity. This research article aims to conduct a numerical study using the nonlinear fi</p> ... Show More
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Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
Retrofitting Reinforced Concrete One–Way Damaged Slabs Exposed to High Temperature
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Exposure of reinforced concrete buildings to an accidental fire may result in cracking and loss in the bearing capacity of their major components, columns, beams, and slabs. It is a challenge for structural engineers to develop efficient retrofitting techniques that enable RC slabs to restore their structural integrity, after being exposed to intense fires for a long period of time. Experimental
investigation was carried out on twenty one slab specimens made of self compacting concrete, eighteen of them are retrofitted with CFRP sheets after burning and loading till failure while three of them (which represent control specimens) are retrofitted with CFRP sheet after loading till failure without burning. All slabs had been tested in a

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Compressive Behavior of Fiber Reinforced Concrete Columns Rehabilitated with CFRP Warps
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Over the last few years, there has been a worldwide increase in the use of composite materials for rehabilitation of deficient reinforced concrete structures. One important application of this technology is the use of Carbon Fiber Reinforced Polymer (CFRP) jacket to provide external confinement of reinforced concrete columns. Square concrete column specimens 100×100×1000 mm with concrete
compressive strength of about 30 and 50 MPa, steel fiber volume fraction 0%, 0.5%, 0.75%, and percentage of longitudinal reinforcement 2.01%, 3.14% and 4.52% were tested until failure in previous research. In this research seven tested columns were repaired and rehabilitated using one layer of CFRP flexible wraps and tested to determine their ultim

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Publication Date
Sun Mar 01 2015
Journal Name
Journal Of Engineering
Retrofitting of Reinforced Concrete Damaged Short Column Exposed to High Temperature
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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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Publication Date
Thu Sep 01 2016
Journal Name
Journal Of Engineering
Response of Laced Reinforced Concrete One Way Slab to Repeated Loading
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Test results of nine reinforced concrete one way slab with and without lacing reinforcement are reported. The tests were designed to study the effect of the lacing reinforcement on the flexural response of one way slabs. The test parameters were considered is the lacing steel ratios of (0, 0.0025, 0.0045, and 0.0065), flexural steel ratios of (0.0025, 0.0045, and 0.0065) and span to the effective depth ratios of (11, 13, and 16). Two specimens had no lacing reinforcement and the remaining seven specimens had the lacing reinforcement. Four point bending test were carried out, one of the specimens was tested under the static load applied gradually up to failure and the other specimens were tested under repeated load (5 cyc

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Publication Date
Tue Mar 15 2022
Journal Name
Al-academy
The culturalization of gender action in the Iraqi theatrical address the play " Revelations as an example"
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The culturalization of gender action occupies a wide range in culture, thoughts and modern studies as well as in fine arts and the ways of expressing them.

       Theater, as one of these arts, plays roles in establishing the fundamental concepts that aims at stating the uncontrollable deed of the social community. It remains one of the most effective and suitable means to confine the uncivilized practices to overcome a certain crisis after gender and cyborg in societies.

        The research concentrates on studying the culturalization of gender action in the Iraqi theatrical address because of the effect it has on the modernizing thought in arts and theater literature. It consists of chapter one which deals w

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