A Laced Reinforced Concrete (LRC) structural element comprises continuously inclined shear reinforcement in the form of lacing that connects the longitudinal reinforcements on both faces of the structural element. This study conducted a theoretical investigation of LRC deep beams to predict their behavior after exposure to fire and high temperatures. Four simply supported reinforced concrete beams of 1500 mm, 200 mm, and 240 mm length, width, and depth, respectively, were considered. The specimens were identical in terms of compressive strength ( 40 MPa) and steel reinforcement details. The same laced steel reinforcement ratio of 0.0035 was used. Three specimens were burned at variable durations and steady-state temperatures (one hour at 500 °C and 600 °C, and two hours at 500 °C). The flexural behavior of the simply supported deep beams, subjected to the two concentric loads in the middle third of the beam, was investigated with ABAQUS software. The results showed that the laced reinforcement with an inclination of 45˚ improved the structural behavior of the deep beams, and the lacing resisted failure and extended the life of the model. The optimal structural response was observed for the specimens. The laced reinforcement improved the failure mode and converted it from shear to flexure-shear failure. The parametric study showed that the lacing bars remarkably improved the strength of the deep beams and they were not affected more by the steady-state temperature and duration. Furthermore, a greater increase in load-carrying capacity was associated with an increase in the flexural diameter of approximately 12 and 16 mm by approximately 24.77% and 87.61%, respectively, compared to the reference LRC deep beams.
This study is a complementary one to an extended series of research work that aims to produce a thermodynamiclly stable asphalt –sulfur blend. Asphalt was physically modified wiht different percentages of asphaltenes , oxidized asphaltenes and then mixed with sulfur as an attempt to obtaine a stable compatible asphalt-sulfur blend. The homogeneneity of asphalt-asphaltenes[oxidized asphaltenes]-sulfur blends were studied microscopically and the results are prsented as photomicrographs. Generally more stable and compatible asphalt-sulfur blends were obtained by this treatment.
Background: this study aimed to evaluate the effect of addition of hydroxyapatite micro filler in three concentrations (5%, 10%, 15%) on surface roughness, impact strength, flexural strength and hardness. Material and methods: One hundred sixty acrylic samples were used in this study,40 samples were used for each test(impact strength ,flexural strength ,hardness and surface roughness).The test group divided into four subgroups(n=10) for controlgroup,5%,10% ,15%H,A.concentration addition groups .Impact testing device, flexural strength testing device, shore hardness tester and profilometer device were used to measure the four tests examined in this study. Results: the results showed a significant increase in impact strength, hardness in all
... Show MoreBackground: The polymethyl methacrylate is the most reliable material for the construction of complete and partial dentures, despite satisfying esthetic demand itsuffered from having unsatisfactory properties like impact strength and transverse strength. This study was designed to improve the impact strength and transverse strength of heat cure acrylic resin by adding untreated and oxygen plasma treated polypropylene fibers and investigate the effect of this additive on some properties of acrylic resin materials. Materials and methods: Untreated and oxygen plasma treated polypropylene fibers was added to PMMA powder by weight 2.5 %. Specimens were constructed and divided into 5 groups according to the using tests; each group was subdivided
... Show MoreThe debate on the methodology of media and communication research is no longer subject to the logic of the contradiction between the quantitative and the qualitative approach, nor the logic of the comparison between them. The nature of the topics presented for research, the problems they raise, the goals to be achieved from the research, and the epistemological positioning of researchers are among the critical factors that dictate the appropriate approach or methodological approaches to conduct their research. This positioning means the implicit philosophical principles upon which any researcher relies and which determine the path he/ she takes to produce scientifically approved knowledge. The method of the researcher's access to the phe
... Show MoreThis study was conducted at the poultry farm located in the College of Agricultural Engineering Sciences, University of Baghdad, Abu Gharib (the old site), and laboratories of the Animal Production Department, Jadriya, to investigate the effect of adding hydrogen peroxide H2O2 at nanoscale levels to semen diluents of local roosters sperm in a number of semen characteristics. In this study, 80 roosters local Iraqi chickens were used, the roosters were trained three times a week, to collect semen, until the largest number of them responded. Then the best 40 of the roosters were elected for the purpose of collecting the semen with a pooled sample, and then the samples were diluted and divided equally into four parts. The concentrations of 0, 1
... Show MoreThe researchers have recently noticed the interest in the problem of overweight and how to find solutions to it until it is now at the forefront in terms of innovating various and different methods and treatment methods, and the interest in developing health fitness is one of the most important requirements of physical activity for the trainees, which led to the multiplicity of sports activities that promote the health aspect For the individual, in addition to the aesthetic aspect, the problem lies in not adopting training programs according to codified scientific foundations aiming, in addition to reducing weight, to raise the general health level of the trainee participating in fitness institutes, as the trainers do not follow the
... Show MoreThis study included the preparation of the mixture aquatic extracts of Peganum harmala seeds and Pericarp of Punica granutum at concentration (10+50) ?(15+55)? (20+60) mgml .To study the influence of the mixture on the percentage of vitality of the protoscolices of E. granulosus In vitro, as the vitality of protoscolices had caused complete death when the using concentration at time 120,90,60 minute respectively. Also study the effect of mixture in white mice with infectious protoscolices In vivo and study the change occurred in the averages of the weights of the liver and spleen and the averages of its distension In vivo in processed group with mixture at concentration (15+55) , (10+50)mgml ,as which was approach to the negative gro
... Show MoreAdministrative leaders conserned to understand the challenges which are faced their organizations and try to assimilate and adapt with the extent that achieves to it efficiency and effective- ess, and standing face to face to faceing any challenge.that threaten it’s existence thro- ugh using modern inputs reached to that level of these challenges and applied the study on a sample deliberate random from teaching hospitals of the Directorate General for Health Baghdad Karkh, and the Directorate General for Health Baghdad Rusafa and the City of Medicine , The importance of t
... Show MoreThe main parameters and methods influencing the removal of Gentian Violet (GV) dye from aqueous media were investigated using a stachy plant in this study. The surface of the stachy plant was determined using FTIR spectra. Adsorption is influenced by the adsorbent's characteristic groups. The research took into account the usual conditions for GV dye adsorption by the stachy plant, such as the impact of contact time. Mass dosage , after 0.3 g the amount of adsorbed dye declines. Study pH and ionic strength, the results obtained showed that at pH 3 the largest adsorption of (GV) was seen, while at pH 9, the lowest adsorption was observed at 298 K, the adsorption kinetics and equilibrium constants were achieved, and the equ
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