Experimental work was carried out to investigate the effect of fire flame (high temperature) on specimens of one way slabs using Self Compacted Concrete (SCC). By using furnace manufactured for this purpose, twenty one reinforced concrete slab specimens were exposed to direct fire flame. All of specimens have the same dimensions. The slab specimens were cooled in two types, gradually by left them in the air and suddenly by using water. After that the specimens were tested under two point loads, to study, the effect of
different: temperature levels (300ºC, 500ºC and 700ºC), and cooling rate (gradually and sudden cooling conditions) on the concrete compressive strength, modulus of rupture, flexural strength and the behavior of reinforced concrete slab specimens and comparing the results with specimens without burning (reference specimens). The results showed that, the concrete compressive strength, concrete modulus of rupture and the flexural strength decreases while the maximum (central) deflection increases with increasing the fire flame temperature. For suddenly cooled specimens the residual flexural strength is less than that of gradually cooled specimens while the deflection is greater. For slabs with 20 MPa concrete strength and gradually cooled, the residual bending strength percent is 81.5%, 75% and 62.3% ,while the increase in central deflection is 5%, 33%, and 105% at burning temperature 300ºC, 500ºC and
700ºC respectively. For suddenly cooled specimens of the same strength and exposed to the same temperatures above the residual flexural strength is 77.9%, 68.3% and 58.3% while the increase in central deflection is 25%, 52%, and 118% respectively. When the strength of concrete specimens increase, the residual flexural strength experiences small increase and the increase is of lower rate in the central deflection for 300 ºC and 500 ºC burn temperatures while the decrease is significant for 700 ºC burning temperature.
This study expands the state of the art in studies that assess torsional retrofit of reinforced concrete (RC) multi-cell box girders with carbon fiber reinforced polymer (CFRP) strips. The torsional behavior of non-damaged and pre-damaged RC multi-cell box girder specimens externally retrofitted by CFRP strips was investigated through a series of laboratory experiments. It was found that retrofitting the pre-damaged specimens with CFRP strips increased the ultimate torsional capacity by more than 50% as compared to the un-damaged specimens subjected to equivalent retrofitting. This indicated that the retrofit has been less effective for the girder specimen that did not develop distortion beforehand as a result of pre-loading. From
... Show MoreThis study expands the state of the art in studies that assess torsional retrofit of reinforced concrete (RC) multi-cell box girders with carbon fiber reinforced polymer (CFRP) strips. The torsional behavior of non-damaged and pre-damaged RC multi-cell box girder specimens externally retrofitted by CFRP strips was investigated through a series of laboratory experiments. It was found that retrofitting the pre-damaged specimens with CFRP strips increased the ultimate torsional capacity by more than 50% as compared to the un-damaged specimens subjected to equivalent retrofitting. This indicated that the retrofit has been less effective for the girder specimen that did not develop distortion beforehand as a result of pre-loading. From
... Show MoreSteel-concrete-steel (SCS) structural element solutions are rising due to their advantages over conventional reinforced concrete in terms of cost and strength. The impact of SCS sections with various core materials on the structural performance of composites has not yet been fully explored experimentally, and in this work, both slag and polypropylene fibers were incorporated in producing eco-friendly steel-concrete-steel composite sections. This study examined the ductility, ultimate strength, failure modes, and energy absorption capacities of steel-concrete-steel filled with eco-friendly concrete, enhanced by polypropylene fiber (PPF) to understand its impact on modern structural projects. Eco-friendly concrete was produced by the partial
... Show MoreOne of the contemporary trends in education and training is the use of educational, competitive and digital games, because one of the most important goals of games is (motivation and challenge). Thus, it ensures the expected reaction from the recipient’s interaction with the game, so we seek his interaction with the content he receives. It is no secret that games distance him from boring content and introduce him to the world of motivation by integrating them with magical elements that make an attractive and desirable game. Naturally, in the case of stimuli and motives that activate the recipient within the context of the educational process procedures, the return is high and especially enjoyable. The aim of the research is to pre
... Show MoreBackground: Waterpipe tobacco smoking has become common especially among young people, Waterpipe smoking misconcepted as a safer mean of smoking, so in this study we will highlight the effect of Waterpipe smoking ‎on periodontal and oral health.‎ Materials and method. The selected ‎‎‎100 male subjects of 30-40 years, ‎categorized into 4 groups (each group ‎‎25 subject): Waterpipe smoker ‎with ‎healthy periodontium, ‎Waterpipe smoker ‎‎with chronic periodontitis, Non-‎‎smoker ‎with healthy periodontium and Non-smoker ‎with chronic periodontitis. Whole ‎unstimulated ‎saliva was collected. Clinical measurements: plaque ‎index
... Show MoreA field experiment was carried out during the seasons 2016 and 2017 in the farm of the Department of Field Crops Science, College of Agricultural Engineering Sciences-University of Baghdad to evaluate the effect of(Aminopyralid + Flurasulam, Coldinafop-propargyl and Flucarbazone-sodium) herbicides and seeding rate (100, 125 and 150) Kg.ha-1 and the interaction between them in growth characteristics, grain and yield components in wheat (Var. IPA99). The results showed that herbicides used were significantly efficient in studied characteristics compared to weedy treatment. Herbicide Flucarbazone-sodium gave higher weed control after 60 and 90 days of spraying the he
MA Mahde, HAA Kadhim, HN Tarish…, Pakistan Heart Journal, 2023 - Cited by 4
Lately great interests have emerged to find educational alternatives to teach and improve motor skills according to modern educational methods that take into account individual differences and speed in learning for the learner through individual learning that the learner adopts by teaching himself by passing through various educational situations to acquire skills and information in the way he is The learner is the focus of the educational process and among these alternatives the interactive video, the researchers noted through the educational training units at the Model Squash School of the Central Union, and that most of the methods and methods used in learning basic skills take a lot of time in the educational program and do not involve
... Show MoreThe current research aims to examine the effect of the rapid learning method in developing creative thinking among second-grade female students in the subject of history. Thus, the researcher has adopted an experimental design of two groups to suit the nature of the research. The sample of the study consists of (36) randomly selected students from Al-Shafaq Secondary School for Women, which are divided randomly into two groups. The first group represents the experimental; it includes (31) students who studied the subject of history using the quick learning method. The second group, on the other hand, is the control group, which consists of (32) students, who studied the same subject using the traditional way. Before starting with the exp
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