The studies on unbonded post-tensioned concrete members strengthened with Carbon Fiber Reinforced Polymers (CFRPs) are limited and the effect of strengthening on the strain of unbonded pre-stressed steel is not well characterized. Estimating the flexural capacity of unbound post-tensioned members using the design methodology specified in the design guidelines for FRP strengthening techniques of bonded post-tensioned members does not provide a reliable evaluation. This study investigates the behavior of unbonded post-tensioned concrete members with partial strand damage (14.3% and 28.6% damage) and strengthened with CFRP laminates using a near-surface mounted technique with and without U-wrap anchorages. The experimental results showed that the use of CFRP laminates significantly affects strand strain, especially with the use of anchors. The CFRP reinforcement affected flexural strength, crack width, and midspan deflection. However, the flexural stiffness of strengthened members during the serviceability phases is critical as strand damage ratios increase. In comparison with the nondamaged girder, the NSM-CFRP laminates enhanced the flexural capacity by 11% and 7.7% corresponding to strand damage of 14.3% and 28.6% respectively. Additionally, semiempirical equations were proposed to predict the actual strain of unbonded strands whilst considering the effects of FRP laminates. The suggested equations are simple to apply and provide accurate predictions with little variance.
Iraq enjoys many factors and ingredients that made it “affect and be affected at the same time” by the American-Iranian conflict from the “strategic geographical position” adjacent to Iran as an important point and that Iraq has been part of this conflict since the last period which witnessed the outbreak of the first Gulf War (1980-1988) because of border problems and a dispute over Shatt al-Arab, and what followed after that, specifically from 2003 when the United States of America and its allies occupied Iraq’s lands and made a political change by the destruction of its security and military institutions. It increased the importance of Iraq in being a subject of competition between the competing parties in exploiting the
... Show MoreThe current investigation conducted to examine the anatomical aspects of the Arum colocasia L. cultured in Iraq. The study included the anatomical characteristics of the different plant parts, including the root, stem and leaf, the results of the study on the vegetative parts were shown the important anatomical characteristics in terms of the form of the sections reviewed and vertical in them, and the study of their tissues, as well as the stomata complexities and the thickness of the epidermis, vascular bundles, pith, additionally the dimensions of mesophyll and in blade of the leaf. The research was conducted as it is one of the monocotyledon plants and because of the lack of anatomical studies on it, therefore it was studied to know the
... Show MoreResearch aims to know the impact beyond the defined in the collection. The research community is the second school students at Baghdad University and a research sample (63) students, the number of experimental group (27) students and a control group (30) students. The researcher was rewarded in variable lifetime for students and educational attainment and educational level of the parents and the educational level of mothers. The researcher has developed a test took the number of paragraphs (20). A test was true after it has been submitted to the Group of arbitrators. The test was consistent with test method used and the reliability coefficient (0, 88). Either the statistical methods used by the researcher are: Pearson correla
... Show MoreCrude oil is one of the most important sources of energy in the world. To extract its multiple components, we need oil refineries. Refineries consist of multiple parts, including heat exchangers, furnaces, and others. It is known that one of the initial operations in the refineries is the process of gradually raising the temperature of crude oil to 370 degrees centigrade or higher. Hence, in this investigation the focus is on the furnaces and the corrosion in their tubes. The investigation was accomplished by reading the thickness of the tubes for the period from 2008 to 2020 with a test in every two year, had passed from their introduction into the work. Where the thickness of more than one point was measured on each tube in the sa
... Show MoreIn this research The study of Multi-level model (partial pooling model) we consider The partial pooling model which is one Multi-level models and one of the Most important models and extensive use and application in the analysis of the data .This Model characterized by the fact that the treatments take hierarchical or structural Form, in this partial pooling models, Full Maximum likelihood FML was used to estimated parameters of partial pooling models (fixed and random ), comparison between the preference of these Models, The application was on the Suspended Dust data in Iraq, The data were for four and a half years .Eight stations were selected randomly among the stations in Iraq. We use Akaik′s Informa
... Show MoreThe present study is concerned with the concept of ethics academically. It aims to investigate the major problems that contemporary Iraqi society suffers from; on top of which is the problem of sectarian and religious intolerance. Such a problem has a major role in the emergence of extremism and terrorism. It further destabilizes the security and stability of the country, exposing, as a result, the lives of citizens to the danger of genocide, disintegrating the social structure, stopping the wheel of development, rampant corruption, and deteriorating the political, social, moral and economic situation. Here comes the role of social work as governmental institutions and civil society organizations in curbing this reprehensible phenomenon
... Show MoreArchitecture has evolved through the ages as forms, relationships, materials and mechanisms according to the data of each era and up to the era of digital technology, where the change in proportions and aesthetic dimensions of contemporary architectural formation due to the capabilities of digitization has created innovative plastic properties using the void formation in the facades and the introduction of void as a formative and aesthetic element, which led to The emergence of new creative concepts and ideas that contradict traditional ideas and are consistent with the spirit of the times, led to a revolution in the world of architectural form at the level of (architectural ideas and the generation of shapes, materials and construction
... Show MoreTo investigate the research objectives, the researchers put the following hypothesis:
There was no statistically significant difference at the level of (0.05) between the average score of the students of the experimental group who studied the language of rhetoric according to model of learning method, and the average score of the students of the control group who studied the same article in the traditional way acquiring rhetorical concept. The researchers relied on the experimental design with the partial setting of the post-test, which depends on the experimental group that is taught using the model of the learning method, and the control group taught using the traditional method.
... Show MoreIn this paper, we present some numerical methods for solving systems of linear FredholmVolterra integral equations of the second kind. These methods namely are the Repeated Trapezoidal Method (RTM) and the Repeated Simpson's 1/3 Method (RSM). Also some numerical examples are presented to show the efficiency and the accuracy of the presented work.