Preferred Language
Articles
/
mRi5Z5UBVTCNdQwCgC24
Experimental and Numerical Behavior of Encased Pultruded GFRP Beams under Elevated and Ambient Temperatures
...Show More Authors

In this research, experimental and numerical studies were carried out to investigate the performance of encased glass-fiber-reinforced polymer (GFRP) beams under fire. The test specimens were divided into two peer groups to be tested under the effect of ambient and elevated temperatures. The first group was statically tested to investigate the monotonic behavior of the specimens. The second group was exposed to fire loading first and then statically tested to explore the residual behavior of the burned specimens. Adding shear connectors and web stiffeners to the GFRP beam was the main parameter in this investigation. Moreover, service loads were applied to the tested beams during the fire. Utilizing shear connectors, web stiffeners, and both enhanced the load-carrying capacities of the encased beams by 100.6%, 97.3%, and 130.8%, respectively. Comparisons between the burned and unburned peer beams were presented with losses in the load-carrying capacity of the burned beams. These losses were the highest in the cases of shear connectors and web stiffeners due to the obtained severe damage, which led to more reductions in the residual behavior of the burned beams. Numerical analyses were performed using the general-purpose finite element (FE) ABAQUS package to conduct a parametric study. The investigated parameters included the effect of the exposure duration and the temperature level. The results of the FE analysis showed good agreement with the experimental results. Additional reductions in the residual capacities of the fire-damaged beams were observed due to exposure to longer fire durations. The improvements in the beam capacities due to using shear connectors and web stiffeners relative to the reference beams under the same exposure time decreased as the exposure duration increased. Furthermore, increasing the temperature to 700 °C, 800 °C, 900 °C, and 950 °C caused reductions in the residual capacities by about 25%, 45%, 70%, and 80%, respectively, for the encased beams in comparison to their peers at ambient temperature.

Scopus Clarivate Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Exact Stiffness Matrix for Nonprismatic Beams with Parabolic Varying Depth
...Show More Authors

In this paper, an exact stiffness matrix and fixed-end load vector for nonprismatic beams having parabolic varying depth are derived. The principle of strain energy is used in the derivation of the stiffness matrix.
The effect of both shear deformation and the coupling between axial force and the bending moment are considered in the derivation of stiffness matrix. The fixed-end load vector for elements under uniformly distributed or concentrated loads is also derived. The correctness of the derived matrices is verified by numerical examples. It is found that the coupling effect between axial force and bending moment is significant for elements having axial end restraint. It was found that the decrease in bending moment was
in the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
Cognitive Behavior Therapy for Depression
...Show More Authors

The current research aimed to identify the cognitive-behavioral therapy on people with depression, through the following hypothesis (there are no statistically significant differences in the sample before and after cognitive-behavioral therapy). The importance of research is highlighted through the use of cognitive-behavioral therapy, to be used in treating depression, anxiety and fears by health institutions. It is also considered as a reference for psychological studies related to this topic to be added to our libraries that already suffer from a scarcity of this type of resources. The cognitive-behavioral therapy was used in the treatment of five male subjects.

The study revealed the existence of statistically significant diff

... Show More
View Publication Preview PDF
Publication Date
Mon Feb 14 2022
Journal Name
Journal Of Educational And Psychological Researches
Animation Films and Their Impact on the Behavior of Kindergarten Child from the Point of View of Mothers
...Show More Authors

The child spends several hours watching animated films, which affect their behavior negatively and positively. This calls parents to monitor what their children are watching, to show them the serious risks of some violent films, and to direct them toward choosing both positive and educational programs that develop their positive behavior. This study aimed to explore the positive and negative effects of watching animation films as well as to identify the role animation films in increasing the cognitive knowledge of kindergarteners. To do this, the descriptive and analytical methods were used. A questionnaire was adopted as a tool for data collection. A scale of (45) items classified into three categories was applied on  the r

... Show More
View Publication Preview PDF
Publication Date
Sun Aug 01 2021
Journal Name
Journal Of Composites For Construction
Prediction of Concrete Cover Separation in Reinforced Concrete Beams Strengthened with FRP
...Show More Authors

View Publication
Publication Date
Thu Jun 01 2023
Journal Name
Results In Engineering
Effectiveness of embedded through-section technique in strengthening reinforced concrete spandrel beams
...Show More Authors

View Publication
Crossref (7)
Crossref
Publication Date
Sat Aug 10 2019
Journal Name
Engineering, Technology & Applied Science Research
Performance of Segmental Post-Τensioned Concrete Beams Exposed to High Fire Temperature
...Show More Authors

The present study illustrates observations, record accurate description and discussion about the behavior of twelve tested, simply supported, precast, prestressed, segmental, concrete beams with different segment numbers exposed to high fire temperatures of 300°C, 500°C, and 700°C. The test program included thermal tests by using a furnace manufactured for this purpose to expose to high burning temperature (fire flame) nine beams which were loaded with sustaining dead load throughout the burning process. The beams were divided into three groups depending on the precast segments number. All had an identical total length of 3150mm but each had different segment number (9, 7, and 5 segments), in other words, different segment length

... Show More
View Publication Preview PDF
Crossref (6)
Crossref
Publication Date
Tue Dec 01 2020
Journal Name
Sn Applied Sciences
Regressor-free adaptive vibration control of constrained smart beams with axial stretching
...Show More Authors

View Publication
Scopus (3)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Sun Aug 01 2021
Journal Name
Journal Of Composites For Construction
Prediction of Concrete Cover Separation in Reinforced Concrete Beams Strengthened with FRP
...Show More Authors

Scopus (17)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Tue Mar 31 2020
Journal Name
Association Of Arab Universities Journal Of Engineering Sciences
Extended Finite Element Analysis of Reinforced Concrete Beams Using Meso-Scale Modeling
...Show More Authors

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 lo

... Show More
Crossref
Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Engineering
Strengthening of Reinforced Concrete T- Section Beams Using External Post-Tensioning Technique
...Show More Authors

This research is carried out to investigate the externally post-tensioning technique for strengthening RC beams. In this research, four T-section  RC beams having the same dimensions and material properties were casted and tested up to failure by applying two mid-third concentrated loads. Three of these beams are strengthened by using external tendons, while the remaining beam is kept without strengthening as a control beam. Two external strands of 12 mm diameter were fixed at each side of the web of the strengthened beams and located at depth of 200 mm from top fiber of the section (dps). So that the depth of strands to overall depth of the section ratio (dps

... Show More
View Publication Preview PDF