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Fire Flame Influence on the Behavior of reinforced Concrete Beams Affected by Repeated Load
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The influence and hazard of fire flame are one of the most important parameters that affecting the durability and strength of structural members. This research studied the influence of fire flame on the behavior of reinforced concrete beams affected by repeated load. Nine self- compacted reinforced concrete beams were castellated, all have the same geometric layout (0.15x0.15x1.00) m, reinforcement details and compressive strength (50 Mpa).

To estimate the effect of fire flame disaster, four temperatures were adopted (200, 300, 400 and 500) oC and two method of cooling were used (graduated and sudden). In the first cooling method, graduated, the tested beams were leaved to cool in air while in the second method, sudden, water splash was used to reduce the temperature. Eight of the tested beams were divided in to four groups, each were burned to one of the adopted temperature for about half an hour and cooled by the adopted cooling methods (one by sudden cooling and the other by graduated cooling). After burning and cooling the beams were tested under the effect of repeated load (loading – unloading) for five cycle and then up to failure.

As a compared with the non- burned beam, the results indicated that the ultimate load capacity of the tested beams were reduced by (16, 23, 54 and 71)% after being burned to (200, 300, 400 and 500) oC , respectively, for a case of sudden cooling and by (8, 14, 36 and 64)% , respectively, for a case of graduated cooling. It was also found that the effect of sudden cooling was greater than that in a case of graduated cooling.

Regarding the failure mode, there was a different between the non-burred beam and the other ones even that all of them had the same geometric layout, compressive strength and reinforcement details. The failure mode for all burned beams was combined shear- flexure failure which was belong to the reduction in the compressive strength of the concrete due to the effect of the temperature rising , while the failure mode of the non-burned beam was flexure failure which was compatible with the preliminary design. It was also detected that the residual deflection proportion directly with the temperature, as the temperature increase to (200, 300, 400 and 500) oC the residual deflection compared with the non-burned beam increased by (32, 48, 326 and 358)% for a case of sudden cooling and by (13, 29, 303 and 332)%  for a case of graduated cooling. Another effect was appear represented by the method of cooling, the results showed that the sudden cooling had more effect on the residual deflection than the graduated cooling by (15-6)% approximately. To vanish the residual deflection, numbers of cycle (loading-unloading) were required. It was found that this number increase as the temperature of burning increased and it’s also larger in a case of sudden cooling.

 

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Publication Date
Sat Dec 11 2021
Journal Name
Engineering, Technology & Applied Science Research
Experimental and Numerical Analysis of the Punching Shear Resistance Strengthening of Concrete Flat Plates by Steel Collars
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In this study, six square reinforced concrete flat plates with dimensions of (1500×1500×100) mm were tested under a concentrated load applied on a column located at the center of the slabs. One of these slabs was the control specimen, whereas, in the others, steel angles (steel collars) were used, fixed at the connection region between the slab and the column to investigate the effect of the presence of these collars on punching shear strength. Five thicknesses were used (4, 5, 6, 8, 10mm) with constant legs of angles (75×75) mm of the steel collars to investigate the effects on the punching shear resistance with respect to the control slab. The results of the experimental study show that the punching shear resistance increased b

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Scopus (9)
Crossref (8)
Scopus Crossref
Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
The influence of Packed Cells Volume (PCV) and Temperature on Erythrocytes Sedimentation Rate (ESR)
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Erythrocytes aggregation is an important physiological phenomenon in the circulation of blood, and is a basic characteristic of normal blood that plays a major role in cardiovascular system especially in the microcirculation. Blood samples have been taken from (30) volunteers (15 male, and 15 female), their ages (20-30) years. The Erythrocytes Sedimentation Rate (ESR) for those subjects was measured at different Packed Cells Volume (PCV) (10%-25%), and also it was measured at different temperature (10oC-25oC). The results show that there was a highly significant decrease (P<0.01) in ESR when the PCV increase and a highly significant increase (P<0.01) in ESR when the temperatures increase. The conclusion from these results is that the ESR va

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Publication Date
Fri Aug 01 2025
Journal Name
Iop Conference Series: Earth And Environmental Science
Influence of Solar and Geomagnetic Activity on the Ionospheric Sporadic-E Layer Over Baghdad
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Abstract<p>This study examines the monthly mean diurnal variations of the ionospheric sporadic E (Es) layer’s critical frequency (<italic>foEs</italic>) and virtual height (<italic>h′Es</italic>) above Baghdad city (latitude 33.3˚N, longitude 44.4˚E) during Solar Cycle 22 (1988–1995). The analysis examines their correlation with solar activity, represented by sunspot numbers, and geomagnetic disturbances, particularly during the descending phase of the cycle. The findings revealed that <italic>foEs</italic> values were the highest during the solar maximum years (1989–1991), aligning with increased sunspot numbers and geomagnetic activity due to coronal mas</p> ... Show More
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Publication Date
Tue Aug 06 2024
Journal Name
Sumer Journal For Pure Science
The Influence of Helicobacter Pylori Infection on Cardiovascular Risk Factors in Patients with Gastritis
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Helicobacter pylori (HP) is the etiopathogenic agent of gastric and duodenal disorders ranging from gastritis to malignancy. It is also associated with many extraintestinal diseases, including cardiovascular disease and its associated risk factors. To evaluate the link between HP infection and some cardiovascular risk factors by studying the effects of HP infection on body mass index, blood pressure, and serum lipid profile among patients having gastritis with and without HP infection. A crosssectional study included 1214 patients who had gastritis diagnosed by gastroscopy examination. Those patients were in the age range of 30-65 years and they were divided according to their gender into 725 females and 489 males depending on the 1

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Publication Date
Sat Jan 20 2018
Journal Name
International Journal Of Medical Research & Health Sciences
The Influence of Thyroid Hormones on Leptin and Resistin Levels in Hyperthyroid Female Patients
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Hyperthyroidism or thyrotoxicosis occurs due to excess release of thyroid hormone. These hormones regulate the body’s energy balance and have effects on adipokine level. There are several reports suggesting interrelation between adipokines (resistin and leptin) with thyroid dysfunction. Objectives: This study was established to investigate the effect of thyroid hormones in hyperthyroidism state on the level of some adipokines, leptin and resistin; in comparison with control. Patients and Methods: The present study included 50 Iraqi female patients with hyperthyroidism with age ranged between 30-58 years and 30 healthy controls with age ranged between 30-53 years. Serum samples were collected from study groups. The levels of thyroid hormon

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Publication Date
Sun Jul 06 2014
Journal Name
Journal Of Educational And Psychological Researches
The influence of Online Training Courses on Iraqi EFL Instructors Teaching and Learning Process
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For over a decade, educational technology has been used sparingly in our schools and universities. Online training courses have been used since 2003 to fill the gaps in our learning system and to add extra program besides classroom learning. This paper aims to investigate the Iraqi EFL instructors’ participating in online training courses and its influence on the process of teaching and learning.

       The sample of present study consists of 30 instructors from University of Baghdad. The questionnaire of sixteen items was constructed. After ensuring validity and reliability of questionnaire, it was applied on March 2013 and the result shows that most of instructors improve their teaching methods b

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Engineering
Improvement of Asphalt Concrete Mixtures by Adding Pulverised Fuel Ash as Filler
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Consuming of by-product or waste materials in highway engineering is significant in the construction of new roads and/or in renovations of the existing ones. Pulverised Fuel ash (PFA), which is a by-product material of burning coal in power stations, is one of these materials that might be incorporated instead of mineral filler in hot asphalt mixtures.

Two types of surface course mixtures have been prepared one with conventional mineral filler i.e. ordinary Portland cement (OPC) while the second was with PFA. Several testings have been conducted to indicate the mechanical properties which were Marshall Stability and Indirect Tensile Strength tests. On the other hand, moisture damage and ageing have been evaluated

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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Investigation of Load and Pressure Distribution on Wing with Wake Rollup for Low Speed Aircraft
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The presented work shows a preliminary analytic method for estimation of load and pressure distributions on low speed wings with flow separation and wake rollup phenomena’s. A higher order vortex panel method is coupled with the numerical lifting line theory by means of iterative procedure including models of separation and wake rollup. The computer programs are written in FORTRAN which are stable and efficient.

      The capability of the present method is investigated through a number of test cases with different types of wing sections (NACA 0012 and GA(W)-1) for different aspect ratios and angles of attack, the results include the lift and drag curves, lift and pressure distributions along the wing s

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Publication Date
Wed Apr 25 2018
Journal Name
Earthquake And Structures
Response of circular footing on dry dense sand to impact load with different embedment depths
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Scopus (8)
Scopus
Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Engineering
Experimental Investigations on the Strength and Serviceability of Biaxial Hollow Concrete Slabs
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Biaxial hollow slab is a reinforced concrete slab system with a grid of internal spherical voids included to reduce the self-weight. This paper presents an experimental study of behavior of one-way prestressed concrete bubbled slabs. Twelve full-scale one-way concrete slabs of (3000mm) length with rectangular cross-sectional area of (460mm) width and (150mm) depth. Different parameters like type of specimen (solid or bubbled slabs), type of reinforcement (normal or prestress), range of PPR and diameter of plastic spheres (100 or 120mm) are considered. Due to the using of prestressing force in bubbled slabs (with ratio of plastic sphere diameter D to slab thickness H, D/H=0.67), the specimens showed an increase in ultimat

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