Corrosion- induced damage in reinforced concrete structure such as bridges, parking garages, and buildings, and the related cost for maintaining them in a serviceable condition, is a source of major concern for the owners of these structures.
Fly ash produced from south Baghdad power plant with different concentrations (20, 25 and 30) % by weight from the cement ratio were used as a corrosion inhibitor as a weight ratio from the cement content.
The concrete batch ratio under study was (1:1.5:3) cement, sand and gravel respectively which is used in Iraq. All the raw materials used were locally manufactured.
Concrete slabs (250x250x70) mm dimensions were casted, using Poly-wood molds. Two steel bars were embedded in the central position of each slab at the mid- height (about 35 mm), with a space of 100 mm between each other.
A 16 concrete slabs were prepared (0, 20, 25 and 30) wt. % of fly ash. The specimens were partially immersed in 3.5 wt. % NaCl solution in order to predict the corrosion.
Half-cell potential test technique was used to estimate the corrosion rate which is occurred in the steel bar due to the migration of chloride ions through the concrete, depending on the ASTM C876-08.
The result shows that the potential values of steel in concrete were shifts to the positive direction with increasing the percentage of fly ash, because the reduction of porosity by the addition of fly ash which fill the pores and inhibit the chloride ions to reach to steel.
The results also show that the further increase of fly ash (30%) the possibility of carbonation is increased which result in reduction its alkalinity, thereby permitting corrosion of embedded steel.
In this paper, effective slab width for the composite beams is investigated with special emphasis on the effect of web openings. A three dimensional finite element analysis, by using finite element code ANSYS, is employed to investigate shear lag phenomenon and the resulting effective slab width adopted in the classical T-beam approach. According to case studies and comparison with limitations and rules stipulated by different standards and codes of practice it is found that web openings presence and panel proportion are the most critical factors affecting effective slab width, whereas concrete slab thickness and steel beam depth are less significant. The presence of web opening reduces effective slab width by about 21%.
... Show MoreFicus (FIC) leaf extract used as corrosion inhibitor for carbon steel alloy (C.S) in two corrosive environments (saline and acidic) with four concentrations (1, 2, 3 and 4 ppm) at varied temperature range between (298-328 K) using electrochemical polarization measurements. The importance of this work focused on the use the green chemistry that is far from the chemical materials effect. The results of polarization presented the FIC inhibitor consider a mixed type (anodic and cathodic) inhibitor. Tafel curve used to evaluate the corrosion inhibition activity. In a saline medium, the best inhibitor efficiency reaches to (87%) in 2 ppm and IE% reach to (99%) for HCl medium inhibited by 1ppm. Langmuir isotherm obeys the study by thermodynamic pa
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It is suitable to use precast steel-concrete composite beams to quickly assemble a bridge or a building, particularly in isolated regions where cast-in-situ concrete is not a practical option. If steel-concrete composite beams are designed to allow demountability, they can also be extremely useful in the aftermath of natural disasters, such as earthquakes or flooding, to replace damaged infrastructure. Furthermore, rapid replacement of slabs is extremely beneficial in case of severe deterioration due to long-term stressors such as fatigue or corrosion. The only way to rapidly assemble and disassemble a steel-concrete composite structure is to use demountable shear connectors to connect/disconnect the steel beams to/from the concrete slab. I
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Low- and medium-carbon structural steel components face random vibration and dynamic loads (like earthquakes) in many applications. Thus a modification to improve their mechanical properties, essentially damping properties, is required. The present study focuses on improving and developing these properties, significantly dampening properties, without losing the other mechanical properties. The specimens used in the present study are structural steel ribbed bar ISO 6935 subjected to heating temperatures of (850, 950, and 1050) ˚C, and cooling schemes of annealing, normalizing, sand, and quenching was selected. The damping properties of the specimens were measured experimentally with the area under the curve for the loadi
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Education by lectures has been standard for 100 years or more. Given the 21st century technology, people can connect with others around the world instantly, electronically. With the pandemic, teaching changed to one-way information transfer with the loss of interpersonal learning experience. SNI® and now SNI Digital™ have been experimenting with different forms of communication to transfer information.
Using an interactive education model, a meeting for neurosurgeons in Baghdad was held for students, residents, and neurosurgeons
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The research aims to identify the strengths and weaknesses in communication skills and decision-making among managers of the Faculty of Physical Education - University of Baghdad from the perspective of staff and faculty members. May be the research community to all employees (faculty and staff) all in the Faculty of Physical Education - Baghdad University for the academic year 2012-2013 and totaling 208 faculty members and 123 staff members, has been selected a random sample of members of the faculty's (100 ) and employees (50) and distributed them to identify the study and collecting them (75) The identification of the faculty and (40) of the staff, and ruled out (35) to identify the lack of validity. After having identified researcher co
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Objective : To assess the efficiency for some disinfectants against the microorganisms isolated from
the wards of newborn and premature babies in Educational Baghdad Hospital .
Methodology :This study had done from 1\8\2014 untile 1\9\2014, we had selected three types of
disinfectants ( Incidine , Bleach and Microbac Forte )which were used for disinfection in the wards of
newborn babies at Educational Baghdad Hospital to assess their effect against the microorganisms
isolated from these wards and study the mixed affect of these disinfectants againt same
microorganisms .
Results : The results of the present study showed that there is affect of the different concentrations of
the used disinfectants against the micro
A survey to show the reality of educational guidance in schools in Baghdad Rusafa 3\ from the point of view of educational guides. It used the analytical descriptive technique. The research community consists of () male and female advisors in schools of Baghdad. The sample was haphazard( 51\.) The questionnaire was made and it consists (50) items. The research statistics have been analyzed by (SPSS), The questionnaires have been used in the first term in (2017-2018) and the results showed the relationship between the advisor and other teachers, the advisor and students fathers and the local society. According to the results, the research made some recommendations and suggestions.
Researchers have shown considerable interest in the idea of organizational climate because of its crucial role in school administration and all school operations. Hence, enhancing it is regarded as a primary duty of school principals, as they bear direct accountability for overseeing the school and its entire operations. Total quality management is a primary method that allows the school administrator to effectively handle administrative tasks with the goal of meeting the needs of instructors, students, staff members, and the community. The significance of the research rests in its attempt to shed light on the value of both organizational climate and total quality management among high school principals. The research seeks to determine the
... Show Morestudy aims to examine education and the challenges of globalization in light of Corona pandemic. The examination involves surveying a randomly selected sample from the University of Baghdad’s professors, particularly from the colleges of Education for Women, Arts, and Sciences. The purpose of this examination is to learn about the dimensions of globalization, its effects on the educational process, and the importance of distance education during the spread of Corona virus quarantine. To achieve this, the researcher followed a descriptive and analytical approach by applying a questionnaire to a sample of 70 teachers who were randomly selected electronically. Results have shown that 78.6% emphasized the contribution of globalization duri
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