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Extended Finite Element Analysis of Reinforced Concrete Beams Using Meso-Scale Modeling
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Four simply supported reinforced concrete (RC) beams were test experimentaly and analyzed using the extended finite element method (XFEM). This method is used to treat the discontinuities resulting from the fracture process and crack propagation in that occur in concrete. The Meso-Scale Approach (MSA) used to model concrete as a heterogenous material consists of a three-phasic material (coarse aggregate, mortar, and air voids in the cement paste). The coarse aggregate that was used in the casting of these beams rounded and crashed aggregate shape with maximum size of 20 mm. The compressive strength used in these beams is equal to 17 MPa and 34 MPa, respectively. These RC beams are designed to fail due to flexure when subjected to load as a two-point loading. To model the coarse aggregate realistically, the aggregate must distributed randomly according to the gradient and amount actually used in the mix design. This property is not found in the ABAQUS program that resulted in the use of an alternate program to represent the aggregate randomly. Next, the random representation of the aggregate were transfered to the ABAQUS program by using commands and instructions that the program can understand, to draw as a sketch. The comparison between experimental and numerical results showed that the XFEM is a good method used to simulate the non-smooth behavior in RC beams such as discontinuitiy and singularity. While a mesoscale model can be simulated the non-homogeneity in the concrete.

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Publication Date
Sat Dec 11 2021
Journal Name
Engineering, Technology & Applied Science Research
Post-Fire Behavior of Non-Prismatic Beams with Multiple Rectangular Openings Monotonically Loaded
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The main objective of this paper is to study the behavior of Non-Prismatic Reinforced Concrete (NPRC) beams with and without rectangular openings either when exposed to fire or not. The experimental program involves casting and testing 9 NPRC beams divided into 3 main groups. These groups were categorized according to heating temperature (ambient temperature, 400°C, and 700°C), with each group containing 3 NPRC beams (solid beams and beams with 6 and 8 trapezoidal openings). For beams with similar geometry, increasing the burning temperature results in their deterioration as reflected in their increasing mid-span deflection throughout the fire exposure period and their residual deflection after cooling. Meanwhile, the existing ope

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Publication Date
Sun Aug 13 2023
Journal Name
Arpn Journal Of Engineering And Applied Sciences
A NEW APPROACH FOR MODELLING THE VIBRATION OF BEAMS UNDER MOVING LOAD EFFECT
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In this paper, a new equivalent lumped parameter model is proposed for describing the vibration of beams under the moving load effect. Also, an analytical formula for calculating such vibration for low-speed loads is presented. Furthermore, a MATLAB/Simulink model is introduced to give a simple and accurate solution that can be used to design beams subjected to any moving loads, i.e., loads of any magnitude and speed. In general, the proposed Simulink model can be used much easier than the alternative FEM software, which is usually used in designing such beams. The obtained results from the analytical formula and the proposed Simulink model were compared with those obtained from Ansys R19.0, and very good agreement has been shown. I

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Publication Date
Sat Dec 11 2021
Journal Name
Engineering, Technology & Applied Science Research
Post-Fire Behavior of Non-Prismatic Beams with Multiple Rectangular Openings Monotonically Loaded
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The main objective of this paper is to study the behavior of Non-Prismatic Reinforced Concrete (NPRC) beams with and without rectangular openings either when exposed to fire or not. The experimental program involves casting and testing 9 NPRC beams divided into 3 main groups. These groups were categorized according to heating temperature (ambient temperature, 400°C, and 700°C), with each group containing 3 NPRC beams (solid beams and beams with 6 and 8 trapezoidal openings). For beams with similar geometry, increasing the burning temperature results in their deterioration as reflected in their increasing mid-span deflection throughout the fire exposure period and their residual deflection after cooling. Meanwhile, the existing ope

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Publication Date
Tue Oct 08 2002
Journal Name
Iraqi Journal Of Laser
Cross-focusing Effect of Two Intense Laser Beams on Electron Plasma Wave Excitation
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This paper presents the effect of relativistic and ponderomotive nonlinearity on cross-focusing of two intense laser beams in a collisionless and unmagnetized plasma. It should be noted here that while considering the self-focusing due to relativistic electron mass variation, the electron ponderomotive density depression in the channel may also be important. Therefore/these two nonlinearties may simultaneously affect the self-focusing process. These nonlinearities depend not only on the intensity of one laser but also on the second laser. Therefore, one laser beam affects the dynamics of the second beam and hence the process of cross-focusing takes place. The electric field amplitude of the excited electron plasma wave (EPW) has been cal

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Publication Date
Thu Jan 01 2015
Journal Name
Journal Of Engineering
Performance Improvement of the Implementation of Concrete Structures in the Construction Sector In Iraq Using The Modern Management Technique “Six Sigma”
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The reality of the field of construction projects in Iraq refers to needing for the development of performance in order to improve quality and reduce defects and errors and to control the time and cost, so there is needing for the application of effective methods in this area, one of the methods that can be applied in this area is the manner of Six Sigma. This research aims to enhance the performance and quality improvement for the construction projects by improving performance in the work of the implementation of the concrete structure depending on the Six Sigma methodology, and for the purpose of achieving the aim of the research, the researcher firstly depends on the theoretical study that include the concepts of qual

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Publication Date
Fri Sep 01 2023
Journal Name
Journal Of Engineering
The Effect of Cohesive Debonding Elimination on Enhancing the Flexural Performance of Damaged Unbonded Prestressed Concrete Girders Strengthened Using NSM CFRP
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This manuscript studied the effect of U-CFRP wrapped sheet anchorage on the flexural performance of unbonded post-tensioned PC members subjected to partial strand damage and strengthened using CFRP Near-Surface Mounting techniques. The program includes six girders as a control girder, a girder with strand damage of 14.2%, and four girders strengthened by CFRP laminates using the NSM technique with and without U-CFRP wrapped sheet anchorages. The testing results show that the strand damage of 14.2% has reduced the flexural strength of the girder by 5.71%. The NSM-CFRP laminate has a significant effect on flexural strength by 17.4%. On the other hand, the application of end U-CFRP wrapped sheet anchorages improves flexural

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Publication Date
Sun Nov 12 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Astudy and Analysis of Geomagnetic Field By using Model of International Geomagnetic Reference Field (IGRF- 2000)
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The IGRF model is the empirical representation of the Earth magnetic field recommended for scientific use by the International Association of Geomagnetism and Aeronomy(IAGA).

Since  the  Geomagnetic   field   has   the  abi lity  to   change  the orientation of satellite, the strength of Geomagnetic field and its horizontal component have been studied.

This paper discusses the phenomenon of the Geomagnetic field intensity and its horizontal component at diferent altitudes and at certain latitudes, the geomagnetic field data is obtained by using IGRF2000 model at Baghdad (44.7 degree East longitude) .

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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Modeling of the Effect of MgO and ZrO2 on Sintering of Alumina
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  This research  studyies the effect of MgO and ZrO2 as additives in sintering Al2O3 . The experimental results are modeled using ( L2 _ regression) technique , sintered density and grain size rate measurments were  accounted by utilizing experimental results of undoped , MgO doped and ZrO2  doped alumina impregrated with spherical large pores in final stage of sintering . The effect of each additive is inhibitian of the grain growth and increasing the densification rate which enhances the kinietics of densification and the removal of large and small pores.

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Publication Date
Wed Jul 31 2019
Journal Name
Journal Of Engineering
Asphaltene Precipitation Modeling of Sadi Formation in Halfaya Iraqi Oil Field
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Asphaltene is a component class that may precipitate from petroleum as a highly viscous and sticky material that is likely to cause deposition problems in a reservoir, in production well, transportation, and in process plants. It is more important to locate the asphaltene precipitation conditions (precipitation pressure and temperature) before the occurring problem of asphaltene deposition to prevent it and eliminate the burden of high treatment costs of this problem if it happens. There are different models which are used in this flow assurance problem (asphaltene precipitation and deposition problem) and these models depend on experimental testing of asphaltene properties. In this study, the used model was equation of

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Publication Date
Mon Mar 02 2020
Journal Name
Iraqi Geological Journal
RESERVOIR MODELING OF MISHRIF FORMATION IN MAJNOON OIL FIELD, SOUTHERN IRAQ
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The Middle Cenomanian-Early Turonian Mishrif Formation includes important carbonate reservoirs in Iraq and some other surrounding countries due to their high reservoir quality and wide geological extension. The 2D models of this study for facies, effective porosity and water saturation indicate the vertical and lateral heterogeneity of the Mishrif Formation reservoir properties in the Majnoon oil field. Construction of 2D reservoir model of the Mishrif Formation to explain the distribution of facies and petrophysical properties (effective porosity and water saturation) by using RockWorks software. The increase of effective porosity is attributed to the presence of shoal facies.The high water saturation is attributed to the existence of rest

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