Preferred Language
Articles
/
nRZCCIcBVTCNdQwC7zBJ
Evaluation of Concrete Material Properties at Early Age
...Show More Authors

This article investigates the development of the following material properties of concrete with time: compressive strength, tensile strength, modulus of elasticity, and fracture energy. These properties were determined at seven different hydration ages (18 h, 30 h, 48 h, 72 h, 7 days, 14 days, 28 days) for four pure cement concrete mixes totaling 336 specimens tested throughout the study. Experimental data obtained were used to assess the relationship of the above properties with the concrete compressive strength and how these relationships are affected with age. Further, this study investigates prediction models available in literature and recommendations are made for models that are found suitable for application to early age concrete. Results obtained indicate that the relationship between the splitting tensile strength and concrete compressive strength can be approximated with a power function between 0.7 and 0.8, and this correlation is not affected by age. Fracture energy of the concrete and modulus of elasticity values obtained in this study correlate well with the square root of the compressive strength and it was found that this relationship holds true for all hydration ages investigated in this paper. Inverse analysis on the wedge-splitting test was conducted to determine the direct tensile strength. Values of tensile strength obtained from the inverse analysis have been validated numerically by carrying out finite element analysis on the wedge split, and anchor pull-out tests. The ratio of the tensile strength obtained from the inverse analysis to the splitting tensile strength was found to be in the range of 0.5–0.9 and 0.7 on average.

Crossref
View Publication
Publication Date
Sun Jan 27 2019
Journal Name
Civil Engineering Journal
Effect of Size and Location of Square Web Openings on the Entire Behavior of Reinforced Concrete Deep Beams
...Show More Authors

This paper presents an experimental and numerical study which was carried out to examine the influence of the size and the layout of the web openings on the load carrying capacity and the serviceability of reinforced concrete deep beams. Five full-scale simply supported reinforced concrete deep beams with two large web openings created in shear regions were tested up to failure. The shear span to overall depth ratio was (1.1). Square openings were located symmetrically relative to the midspan section either at the midpoint or at the interior boundaries of the shear span. Two different side dimensions for the square openings were considered, mainly, (200) mm and (230) mm. The strength results proved that the shear capacity of the dee

... Show More
Scopus (19)
Crossref (17)
Scopus Clarivate Crossref
Publication Date
Sun Jan 27 2019
Journal Name
Civil Engineering Journal
Effect of Size and Location of Square Web Openings on the Entire Behavior of Reinforced Concrete Deep Beams
...Show More Authors

This paper presents an experimental and numerical study which was carried out to examine the influence of the size and the layout of the web openings on the load carrying capacity and the serviceability of reinforced concrete deep beams. Five full-scale simply supported reinforced concrete deep beams with two large web openings created in shear regions were tested up to failure. The shear span to overall depth ratio was (1.1). Square openings were located symmetrically relative to the midspan section either at the midpoint or at the interior boundaries of the shear span. Two different side dimensions for the square openings were considered, mainly, (200) mm and (230) mm. The strength results proved that the shear capacity of the dee

... Show More
View Publication
Crossref (17)
Crossref
Publication Date
Fri Dec 01 2023
Journal Name
Case Studies In Construction Materials
Experimental and environmental investigations of the impacts of wood sawdust on the performance of reinforced concrete composite beams
...Show More Authors

View Publication Preview PDF
Scopus (17)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Engineering
Development the Mechanical Properties of (AL-Li-Cu) Alloy
...Show More Authors

The aim of this research is to develop mechanical properties of a new aluminium-lithium-copper alloy. This alloy prepared under control atmosphere by casting in a permanent metal mould. The microstructure was examined and mechanical properties were tested before and after heat treatment to study the influence of heat treatment on its mechanical properties including; modulus of elasticity, tensile strength, impact, and fatigue. The results showed that the modulus of elasticity of the prepared alloy is higher than standard alloy about 2%. While the alloy that heat treated for 6 h and cooled in water, then showed a higher ultimate tensile stress comparing with as-cast alloy. The homogenous heat treatment gives best fatigue

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 15 2020
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees20
Studying properties of propagated transverse modes through optical fibers
...Show More Authors

View Publication
Scopus (5)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Sat Jun 01 2019
Journal Name
Geoderma
Effect of cover crop management on soil hydraulic properties
...Show More Authors

View Publication
Scopus (77)
Crossref (77)
Scopus Clarivate Crossref
Publication Date
Mon Jun 30 2003
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Interfacial Rheological Properties of Iraqi Crude Oils Water System
...Show More Authors

View Publication Preview PDF
Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Structural and electrical properties of CdO/porous-Si heterojunction
...Show More Authors

The electrical properties of CdO/porous Si/c-Si heterojunction prepared by deposition of CdO layer on porous silicon synthesized by electrochemical etching were studied. The structural, optical, and electrical properties of CdO (50:50) thin film prepared by rapid thermal oxidation were examined. X-ray diffraction (XRD) results confirmed formation of nanostructured silicon layer the full width half maximum (FWHM) was increased after etching. The dark J-V characteristics of the heterojunction showed strong dependence on etching current density and etching time. The ideality factor and saturation current of the heterojunction were calculated from J-V under forward bias. C-V measurements confirmed that the prepared heterojunctions are abrupt

... Show More
View Publication Preview PDF
Publication Date
Sun Nov 01 2020
Journal Name
Journal Of Engineering
Hydrated Lime Effects on Geotechnical Properties of Clayey Soil
...Show More Authors

Cohesive soils present difficulties in construction projects because it usually contains expansive clay minerals. However, the engineering properties of cohesive soils can be stabilized by using various techniques. The research aims to elaborate on the influences of using hydrated lime on the consistency, compaction, and shear strength properties of clayey soil samples from Sulaimnai city, northern Iraq. The proportions of added hydrated lime are 0%, 2.5%, 5%, 7.5% and 10% to the natural soil sample. The results yielded considerable effects of hydrated lime on the engineering properties of the treated soil sample and enhancement its strength. The soil's liquid limit, plasticity index, and optimum moisture content were de

... Show More
View Publication Preview PDF
Crossref (7)
Crossref
Publication Date
Sat Jan 01 2011
Journal Name
Iraqi Journal Of Physics
A.C Conductivity and Dielectric Properties of Epoxy - TiO2 Nanocomposites
...Show More Authors

In this paper, A.C conductivity of micro and nano grain size- TiO2 filled epoxy composites is measured. The dielectric material used is epoxy resin, while micro and nano-sized titanium dioxide (TiO2) of grain size (1.5μm, and 50nm) was used as filler at low filler concentrations by weight (3%, and 5%). Additionally the effect of annealing temperature range (293-373)º K and at a frequency range of 102-106 Hz on the A.C conductivity of the various specimens was studied.
The result of real permittivity for micro and nanocomposite show that the real permittivity increases with decreasing frequency at range of 102-106Hz. The micron-filled material has a higher real relative permittivity than the nano-filled this is true at all the temper

... Show More
View Publication Preview PDF