Preferred Language
Articles
/
RIbNtoYBIXToZYALb7Pr
Post-fire serviceability and residual strength of composite post-tensioned concrete T-beams
...Show More Authors
Abstract<p>In this study, the response of ten composite post-tensioned concrete beams topped by a reinforced concrete deck with adequate reinforcing shear connectors is investigated. Depending on the concrete compressive strength of the deck slab (20, 30, and 40 MPa), beams are grouped into three categories. Seven of these beams are exposed to a fire attack of 700 and 800 °C temperature simultaneously with or without the presence of a uniformly distributed sustained static loading. After cooling back to ambient temperature, these composite beams are loaded up to failure, using a force control module, by monotonic static loading in a four-point-bending setup with two symmetrical concentrated loads applied in the middle third of the effective span. The objectives of this study include investigating the behavior of the composite prestressed concrete beams under and after the exposure to a direct fire flame, as well as finding their residual load-carrying capacity. Tests demonstrate significant deteriorations caused by exposure to high temperatures associated with the increase of the member’s camber. The increase of the midspan camber after heating exposure reached approximately 200%. On the other hand, the 1-h steady-state exposure of test specimens to temperatures of 700 and 800 °C led to reduce the load-carrying capacity of the heat-deteriorated beams up to 45% and 54%, respectively.</p>
Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Sep 01 2015
Journal Name
Journal Of Engineering
Impact of Aggregate Gradation and Filler Type on Marshall Properties of Asphalt Concrete
...Show More Authors

As asphalt concrete wearing course (ACWC) is the top layer in the pavement structure, the material should be able to sustain stresses caused by direct traffic loading. The objective of this study is to evaluate the influence of aggregate gradation and mineral filler type on Marshall Properties.  A detailed laboratory study is carried out by preparing asphalt mixtures specimens using locally available materials including asphalt binder (40-50) penetration grade, two types of aggregate gradation representing SCRB and ROAD NOTE 31 specifications and two types of  mineral filler including limestone dust and coal fly ash. Four types of mixtures were prepared and tested. The first type included SCRB specification and

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Effect of high and low density polyethylene on some mechanical properties of concrete
...Show More Authors

The increasing use of plastics in various aspects of modern life resulted in the availability of enormous amount of wastes, including a negative effect on the environment and humans. So it is necessary to find solutions to deal with these wastes and ensure to use them as solutions to use in concrete mix . In this research the production of concrete containing high and low density polyethylene has been used by (5, 10, 15)% as a replacement of part of the volume of sand, so as to obtain concrete good compressive strength as well as other benefits such as improved possibility of pumping concrete and reduce the loss of concrete for workability polymer is a material that is non-absorbable of water . It is also intended to dispose of these was

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Some Durability Test of No-Fine Concrete
...Show More Authors

In this study, two types of mixes were adopted by using two grading of coarse aggregate. The practical side of this study was to produce no-fine aggregate concrete by using crushed clay brick aggregates. The durability of the produced concrete and internal sulfate attack was studied.      For durability assessment, it is found that the no-fine concrete made with crushed brick aggregate lost about (15-25) % of its compressive strength after being subjected to 60 cycles of wetting and drying with age 120 days. The curing condition showed that the water curing improved the compressive strength with a rate higher than that when sealed or air dry curing were used. The crushed brick no-fine concrete de

... Show More
View Publication Preview PDF
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Corrosion-Resistance Characteristics of Concrete Containing Furfural
...Show More Authors

Corrosion inhibiting admixtures are unique among other methods to protect reinforced concrete from corrosion damage. In this study, the effect of furfural on the fresh and hardened properties of concrete mixes of 35 and 45 MPa compressive strengths as well as the corrosion inhibition of furfural was evaluated. Furfural was added at different dosages (1, 2 and 3% by weight of cement) with and without superplasticizer (HRWR). Different electrochemical measurements were performed (Half-cell potential, Tafel plot and linear polarization resistance). Electrochemical measurements confirmed that furfural dramatically reduces the rate of corrosion; the inhibition efficiencies were 62.7 and 63.8 % due to 3% furfural addition to 35 and 45MPa-concr

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue May 01 2018
Journal Name
Journal Of Engineering
The Improvement of Thermal Insulating Concrete Panel
...Show More Authors

The Iraqi houses flattening the roof by a concrete panel, and because of the panels on the top directly exposed to the solar radiation become unbearably hot and cold during the summer and winter. The traditional concrete panel components are cement, sand, and aggregate, which have a poor thermal property. The usage of materials with low thermal conductivity with no negative reflects on its mechanical properties gives good improvements to the thermal properties of the concrete panel. The practical part of this work was built on a multi-stage mixing plan. In the first stage the mixing ratio based on the ratios of the sand to cement. The second stage mixing ratios based on replacing the coarse aggregate quantities with the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri May 31 2019
Journal Name
Journal Of Engineering
Moisture Damage of Warm Mix Asphalt Concrete
...Show More Authors

Implementation of Warm Mix Asphalt concrete (WMA) is getting global acceptance due to the restrictions for protecting the environment and the requirements to reduce fuel consumption. In this investigation, two WMA mixtures have been prepared in the laboratory using medium curing cutback (MC-30) and Cationic emulsion asphalt. Hot Mix Asphalt (HMA) was also prepared for comparison. The cylinder specimens (63.5mm) in height and (101.6mm) in diameter were constructed from the mixtures and subjected to indirect tensile strength test to determine the Tensile Strength Ratio (TSR). The cylinder specimens of (101.6mm) in height and (101.6mm) in diameter were also constructed from those mixtures and subjected to static compressive

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Nov 03 2021
Journal Name
Journal Of Engineering Research
Performance of quadrilateral perforated prestressed concrete rafters
...Show More Authors

This study focuses on the behavior of simply supported perforated prestressed concrete rafters (PPCRs) under single midspan monotonic static loading. The experimental program consisted of testing seven specimens; one solid (control) rafter, and six perforated with quadrilateral openings. The main investigated variables are the number and height of the openings. The test findings indicate that, in comparison to the solid rafter, the presence of quadrilateral openings in the PPCRs led to reducing the load capacity by (4.3-36%) and increase the midspan deflection at ultimate by (14.8-33%). Also, increasing the number of concrete posts between openings resulted in increasing the failure load and decreasing the deflection at all stages o

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Thu Sep 30 2004
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Corrosion Inhibition of Steel Reinforcement in Concrete
...Show More Authors

View Publication Preview PDF
Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Engineering
Fatigue Behavior of Modified Asphalt Concrete Pavement
...Show More Authors

Fatigue cracking is the most common distress in road pavement. It is mainly due to the increase in the number of load repetition of vehicles, particularly those with high axle loads, and to the environmental conditions. In this study, four-point bending beam fatigue testing has been used for control and modified mixture under various micro strain levels of (250 μƐ, 400 μƐ, and 750 μƐ) and 5HZ. The main objective of the study is to provide a comparative evaluation of pavement resistance to the phenomenon of fatigue cracking between modified asphalt concrete and conventional asphalt concrete mixes (under the influence of three percentage of Silica fumes 1%, 2%, 3% by the weight of asphalt content), and (chan

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Engineering
Analysis of Prosthetic Running Blade of Limb Using Different Composite Materials
...Show More Authors

Prostheses are used as an alternative to organs lost from the body. Flex-Foot Cheetah is considered one of the lower limb prostheses used in high-intensity activities such as running. This research focused on testing two samples of Flex-Foot Cheetah manufactured of two various materials (carbon, glass) with polyester and compare between them to find the foot with the best performance in running on the level of professional athlete. In the numerical analysis, the maximum principal stress, maximum principal elastic strain, strain energy; finally, the blade total deformation were calculated for both feet. In experimental work, the load-deflection test was done for foot to calculate the bending the results were very close to

... Show More
View Publication Preview PDF
Crossref (10)
Crossref