Preferred Language
Articles
/
3Yath4YBIXToZYALxIzt
Behavior of Post-Tensioned Concrete Girders Subject to Partially Strand Damage and Strengthened by NSM-CFRP Composites
...Show More Authors

Studies on the flexural behavior of post-tensioned beams subjected to strand damage and strengthened with near-surface mounted (NSM) technique using carbon fiber-reinforced polymer (CFRP) are limited and fail to examine the effect of CFRP laminates on strand strain and strengthening efficiency systematically. Furthermore, a design approach for UPC structures in existing design guidelines for FRP strengthening techniques is lacking. Hence, the behavior of post-tensioned beams strengthened with NSM-CFRP laminates after partial strand damage is investigated in this study. The testing program consists of seven post-tensioned beams strengthened by NSM-CFRP laminates with three partial strand damage ratios (14.3% symmetrical damage, 14.3% asymmetric damage, and 28.6% symmetrical damage). The experimental results showed that the use of CFRP laminates significantly increases the flexural capacity by up to 17.4 to 20.4%, corresponding to a strand damage ratio of 14.3 and 28.6%, respectively, enhances the stiffness, and reduces strand strain by up to 15.8 to 22.2%. However, the flexural stiffness of strengthened beams during serviceability phases is critical as strand damage ratios increase. Additionally, semi-empirical equations were proposed to predict the actual strain of unbonded strands whilst considering the effects of CFRP laminates. The suggested equations provide accurate predictions with little variance. Doi: 10.28991/CEJ-2022-08-07-013 Full Text: PDF

Scopus Clarivate Crossref
Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Empirical Equations for Analysis of Two-Way Reinforced Concrete Slabs
...Show More Authors

There are many different methods for analysis of two-way reinforced concrete slabs. The most efficient methods depend on using certain factors given in different codes of reinforced concrete design. The other ways of analysis of two-way slabs are the direct design method and the equivalent frame method. But these methods usually need a long time for analysis of the slabs.

In this paper, a new simple method has been developed to analyze the two-way slabs by using simple empirical formulae, and the results of final analysis of some examples have been compared with other different methods given in different codes of practice.

The comparison proof that this simple proposed method gives good results and it can be used in analy

... Show More
View Publication Preview PDF
Publication Date
Wed Apr 05 2023
Journal Name
Journal Of Engineering
Punching Shear Strength of Reinforced Concrete Flat Plates with Openings
...Show More Authors

Test results of six half-scale reinforced concrete flat plates connections with an opening in the vicinity of the column are reported. The test specimens represent a portion of a slab bounded by the lines of contraflexure around the column. The tests were designed to study the effect of openings on the punching shear behavior of the slab-column connections. The test parameters were the location and the size of the openings. One specimen had no opening and the remaining five had various arrangements of openings around the column. All specimens were cast with normal density concrete of approximately 30 MPa compressive strength. The openings in the specimens were square, with the sides parallel to the sides of the column. Three sizes of ope

... Show More
View Publication Preview PDF
Crossref (16)
Crossref
Publication Date
Mon Aug 01 2011
Journal Name
Journal Of Engineering
PROPERTIES OF HARDENED CONCRETE USING CRUSHED CLAY BRICK AS AGGREGATES
...Show More Authors

This paper provides the result of an investigation to use of crushed clay brick as
aggregates in producing concrete. Eight different crushed clay brick aggregate concretes were
used in this investigation. Compressive strength, splitting tensile strength and pulse velocity of
crushed clay brick aggregates concrete were determined and compare to natural aggregate
concrete. The compressive strength of crushed clay brick aggregates concretes were always
lower than the compressive strength of natural aggregates concrete regardless the age of
concrete, but the crushed clay brick aggregates concrete showed better performance as the age of
concrete increases and average reduction in compressive strength were 33.5% at the age

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Thu Dec 01 2022
Journal Name
Civil And Environmental Engineering
Performance of Prestressed Concrete Hunched Beams with Multi-Quadrilaterals Openings
...Show More Authors
Abstract<p>A long-span Prestressed Concrete Hunched Beam with Multi-Quadrilateral Opening has been developed as an alternative to steel structural elements. An experimental program was created and evaluated utilizing a single mid-span monotonic static load on simply supported beams, which included six beams with openings and the solid control beam without openings, to investigate the performance of such beams. The number and height of the quadrilateral openings are the variables to consider. According to test results, the presence of openings in the prestressed concrete hunched beam with multi-quadrilateral opening did not considerably affect their ultimate load capacity with respect to a contro</p> ... Show More
View Publication Preview PDF
Scopus (1)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Journal Of Engineering
Some properties of Reactive Powder Concrete Contain Recycled Glass Powder
...Show More Authors

Every year, millions of tons of waste glass are created across the globe. It is disposed of in landfills, which is unsustainable since it does not disintegrate into the environment. This study aims to produce reactive powder concrete by using recycled glass powder and determine the influence on the mechanical properties. This study investigated the effect of partial replacement of cement with recycled glass powder at two percentages (0, 20) % by weight of cement on some mechanical properties (Fresh density, Splitting tensile strength, Impact Strength, and voids%) of reactive powder concrete containing 1 % micro steel (MSRPC). Furthermore, using steam curing for (5 hours) at 90 degrees celsius after hardening the sample directly, RPC was

... Show More
View Publication
Crossref (4)
Crossref
Publication Date
Wed May 31 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Corrosion Behavior of Different Gauges of Stainless Steel Wire Use in Removable Partial Denture and Orthodontics Appliances
...Show More Authors

  Wires are commonly used for the construction of orthodontic appliances and occasionally as wrought clasps and rests on partial dentures.           The corrosion resistance is the most important properties of dental alloy. Corrosion process reported to cause a numerous adverse effects on both living tissue and restoration .The conditions in the mouth are very suitable for the occurrence of corrosion. The main objective of this study was to evaluate the corrosion behavior of different gauges of stainless steel wire in artificial saliva .Four gauges of dental stainless steel wire used in orthodontic and removable partial denture were used in this study 0.6mm.,0.7mm.,0 .8mm.&1.0mm.

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Extraction and Estimation of β-carotene Pigment from Some Species of The Genus Rhodotorula and Study The Ability to Increas Their Production By Mutagenesis
...Show More Authors

Beta-carotene pigment was extracted from 6 strains collected from different sources related to some species of the genus Rhodotorula sp. The maximum productivity was in the strain Rhodotorula  mucilaginosa BA61 with amount 10.25 gm/l. The minimum productivity was from the strain R. minuta BA78 with amount 5.39 gm/l. The effects of the chemical mutagen (MNNG) and the physical mutagen (UVC) on the viability of the strains was studied. The results revealed that the chemical mutagen (MNNG) with the concentration 0.2 mg/ml has the clear effect on the viability of the strains , which killing percentage reached to 65.91% in the strain R. minuta BA78. Results of the study of mutagenesis with UVC showed that increase in killing percentage fo

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Unemployment Rates in Iraq and the Extent of the Contribution of Loans Granted by Banks to Finance Small and Medium Enterprises in Reducing Them
...Show More Authors

This study examined the phenomenon of unemployment in Iraq and the extent of the contribution of these loans granted by banks to finance small and medium enterprises in reducing their rates. The temporal boundaries of the study included the period between (2012-2018). The spatial boundaries consisted of random sampling of six Iraqi banks) Where the government banks included (Rafidain, Rasheed and industrial), private banks included (the Iraqi Islamic Bank and the Gulf Commercial Bank and the Bank of the Middle East). In order to achieve the objective of the research in the light of the hypotheses drawn up, the research divided into three topics, the first section highlighting the reality of small and medium enterprises in Iraq and the lo

... Show More
View Publication Preview PDF
Publication Date
Tue Aug 01 2023
Journal Name
Baghdad Science Journal
Isolation and Classification of Green Alga Stigeoclonium attenuatum and Evaluation of its Ability to Prepare Zinc Oxide Nanoflakes for Methylene Blue Photodegradation by Sunlight
...Show More Authors

           Algae have been used in different applications in various fields such as the pharmaceutical industry, environmental treatments, and biotechnology. Studies show that the preparation of nanoparticles by a green synthesis method is a promising solution to many medical and environmental issues. In the current study, the green alga Stigeoclonium attenuatum (Hazen) F.S. Collins 1909 was isolated and identified from the Al-Hillah River (Governorate of Babylon) in the middle of Iraq. The green synthesis by the aqueous extract of algae was used to prepare the nanoflakes of ZnO. Nanoflakes of ZnO are characterized by X-Ray diffraction (XRD) and scanning electron microscope (SEM) with flakes shape and dimensions ranging be

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Post-evaluation of the strategic projects of the Directorate of Public Municipalities - Case study for the period (2004-2015
...Show More Authors

The research aims at conducting a follow-up evaluation of a number of strategic projects implemented by the Directorate of Public Municipalities, one of the Ministry of Construction, Housing and Municipalities and Public Works. The sample included (35) varied strategic projects implemented in most Iraqi governorates. Buildings, municipal buildings, minarets, massacres, multi-story parking, paving and rehabilitation of streets and residential neighborhoods. The difference between the actual and planned times and costs of these projects was then measured and analyzed. These projects were used as a tool for collecting data and information. The questionnaire included four axes, each representing one of the parties to the project, whi

... Show More
View Publication Preview PDF
Crossref