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.
In this study, nano TiO2 was prepared with titanium isopropoxide (TTIP) as a resource to titanium oxide. The catalyst was synthesized using phosphotungstic acid (PTA) and, stearyl trimethyl ammonium bromide (STAB) was used as the structure-directing material. Characterization of the product was done by the X-ray diffraction (XRD), X-ray fluorescent spectroscopy (XRF), nitrogen adsorption/desorption measurements, Atomic Force Microscope (AFM) and Fourier transform infrared (FTIR) spectra, were used to characterize the calcined TiO2 nanoparticles by STAB and PWA. The TiO2 nanomaterials were prepared in three crystalline forms (amorphous, anatase, anatase-rutile). The results showed that the nanoparticles of anatase TiO2 have good cata
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The current study investigates the impact of virtual reality technology on industrial product design. The focus of this study is on the development of industrial products that utilize virtual reality technology, specifically examining the effects of this technology on the visual and design aspects of these products. The aim is to continuously improve the functionality of industrial products and enhance the user experience through virtual reality integration.
The first chapter of the study addresses the research problem, which centers around exploring the technological influence of virtual reality used in industrial products and understanding the functionalities it brings to the design process. Virtual reality technology facilitates th
This research included the study of different factors that may effect on gatifloxacin stability (anew quinolone synthetic antibacterial agent) in its aqueous solution in order to develop and optimize the best delivary of the drug to the eye (as eye drop) with maximum local concentration and minimum systemic absorption and toxicity.Different formulas of gatifloxacin solution for ophthalmic use (0.3%)w/v were prepared in citrate, acetate,citrate/phosphate and phosphate buffers,their tonicity adjusted with suitable quantity of sodium chloride.The effect of different factors that might affectthe stability of gatifloxacin in its prepared ophthalmic solution was studied and determined spectrophotometrically at 287 nm. The results showed t
... Show Moreالخلاصة Bahraini Parliamentary Elections and their Impact on the Popular Uprising) Bahrain has a distinguished constitutional and parliamentary experience, which distinct it from the other Gulf Cooperation Council (GCC) countries. Its experience in this area is the second after the experience of Kuwait to establish a system of government based on modern constitutional principles. As the government presented the Constitution to the Constituent Assembly elected by people and approved in 09/06/1973. After that, it witnessed the birth of the first parliament elected by the people in 1973, but the experiment did not last long and the parliament dissolved by Prince, and didn’t determine the period of the return of the working with the
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Controls Scanning on the slippers a study fiqhiat Comparison
The subject of this research is an important topic, which is frequently repeated, and people need to know its wisdom, and has made it in front and the preface and three detectives, showed through discussion the meaning of the survey on the socks, its wisdom, its rules and conditions, and the duration of the survey on it, spoiled and reasoned and compared to the doctrinal doctrines, And the most correct statement of words I have concluded with a number of things, as follows:
- The need to ensure that the slippers are clean, visible and inwa
The Internet makes the world like a small village. It has the ability to make groups of the same ideas, thoughts, and identity close to each other by gathering them in one place. It is a way to communicate and share information and opinion; shaping and sharing of comprising individuals with common interests and the participation of individuals in a fruitful dialogue results in achieving a set of goals promote ideas and mobilizing people about issues and events of common interests.
To address the relationship of the internet via interactive communication and its ability to achieve social capital and discuss issues and various social events, the study sees that the problem of the study could be formulated as follows:
Consid
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This research test the relationship and the effect of an explanatory variable transparency in the organizational reputation responder variable by senior management in the departments of the Ministry of Housing and Construction centrally funded, As well as come out among other recommendations contribute to the achievement of organizational reputation of the organizations surveyed. Given the importance of the research topic for the public sector and the community and the environment in which they operate researcher designed questionnaire containing (30) items, and collected data from (92) respondents, representing the research community (eight establishments) exclusively and comprehensively, relying descriptive analytic
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