The disposal of the waste material is the main goal of this investigation by transformation to high-fineness powder and producing self-consolidation concrete (SCC) with less cost and more eco-friendly by reducing the cement weight, taking into consideration the fresh and strength properties. The reference mix design was prepared by adopting the European guide. Five waste materials (clay brick, ceramic, granite tiles, marble tiles, and thermostone blocks) were converted to high-fine particle size distribution and then used as 5, 10, and 15% weight replacements of cement. The improvement in strength properties is more significant when using clay bricks compared to other activated waste ceramics and granite tiles. The percentage increases to 11.59% at 28 days for compressive strength when using 10% replacement of cement weight. The ability to produce eco-SCC with less cement content and lower cost consumption is encouraged, although the enhancement in strength is not high since the waste can be disposable. While the percentage reduction in the strength of SCC mixes containing marble tile or thermostone block powder increases with the replacement of cement weight with a greater need for superplasticizer justification, we recommend using 5% as a replacement by weight of cement with an insignificant retardation of strength. Finally, there is a good relationship between compressive strength and ultrasonic pulse velocity and between tensile and flexural strength with a high
In this research, the structural behavior of reinforced concrete columns made of normal and hybrid reactive powder concrete (hybrid by steel and polypropylene fibers) subjected to chloride salts with concentration was 8341.6 mg/l. The study consists of two parts, the first one is experimental study and the second one is theoretical analysis. Three main variables were adopted in the experimental program; concrete type, curing type and loading arrangement. Twenty (120x120x1200) mm columns were cast and tested depending on these variables. The samples were reinforced using two different bars; Ø8 for ties and Ø12 with minimum longitudinal reinforcement (0.01Ag). The specimens were divided into two main groups based o
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The aim of the research is to identify the effect of using the self-questioning strategy on the achievement of fourth-grade students in science and the development of their reflective thinking in physics in the city of Baghdad. The research sample was divided into two groups: an experimental group of (20) students and a control group of (20) students. The researchers developed two tools: a test of (40) multiple-choice questions. The second tool is a test to measure the reflective thinking skills of fourth-grade students. It consists of (25) multiple-choice questions distributed on skills as follow: reflection and observation, detection of inaccuracies, reaching conclusions, giving clear explanations, an
... Show MoreResearch aims to develop a novel technique for segmental beam fabrication using plain concrete blocks and externally bonded Carbon Fiber Reinforced Polymers Laminates (CFRP) as a main flexural reinforcement. Six beams designed an experimentally tested under two-point loadings. Several parameters included in the fabrication of segmental beam studied such as; bonding length of carbon fiber reinforced polymers, the surface-to-surface condition of concrete segments, interface condition of the bonding surface, and thickness of epoxy resin layers. Test results of the segmental beams specimens compared with that gained from testing reinforced concrete beam have similar dimensions for validations. The results show the effectiven
... Show MoreBiaxial hollow slab is a reinforced concrete slab system with a grid of internal spherical voids included to reduce the self-weight. This paper presents an experimental study of behavior of one-way prestressed concrete bubbled slabs. Twelve full-scale one-way concrete slabs of (3000mm) length with rectangular cross-sectional area of (460mm) width and (150mm) depth. Different parameters like type of specimen (solid or bubbled slabs), type of reinforcement (normal or prestress), range of PPR and diameter of plastic spheres (100 or 120mm) are considered. Due to the using of prestressing force in bubbled slabs (with ratio of plastic sphere diameter D to slab thickness H, D/H=0.67), the specimens showed an increase in ultimat
... Show MoreNon-biodegradability of rubber tires contributes to pollution and fire hazards in the natural environment. In this study, the flexural behavior of the Rubberized Reactive Powder Concrete (RRPC) beams that contained various proportions and sizes of scrap tire rubber was investigated and compared to the flexural behavior of the regular RPC. Fresh properties, hardened properties, load-deflection relation, first crack load, ultimate load, and crack width are studied and analyzed. Mixes were made using micro steel fiber of the straight type, and they had an aspect ratio of 65. Thirteen beams were tested under two loading points (Repeated loading) with small-scale beams (1100 mm, 150 mm, 100 mm) size.
The fine aggregate
... Show MoreThis research seeks to try to address one of the important issues in society that prevents the state from achieving its social, economic, political and financial goals, represented by the low tax proceeds, through which it can achieve those goals. What is reflected on the tax proceeds, knowing that the General Tax Authority does not take into account the issue of analyzing the opportunity cost of corporate capital as one of the profit indicators when setting the annual controls, which leads to a decrease in the tax proceeds, and therefore the research objective will be to shed light on the importance of adopting the concept of analysis The opportunity cost by the General Tax Authority to achieve a tax proceeds commensurate with t
... Show MoreThe use of the entrance diffraction hexagon continuous improvement of operations in order to achieve the rationalization of activities, costs and efficiency in the use of available resources and reduce the incidence of damage and waste and recycling, as the accounting information system does not meet the surface production processes oil fields cost management requirements in the measurement and evaluation of the costs of each activity and development of indicators to evaluate the efficiency and effectiveness of production processes and to cover the shortcomings of currently approved by the company so cost accounting system has Find addressed the use of strategic cost management techniques, including the entrance diffraction hexagon for c
... Show MoreThis research set to indicate the role of the opportunity cost in the overall economic development (human and social development) by selecting the most appropriate alternative for the growth of the country in exchange for sacrificing profit limits to achieve this growth and development of the country, especially in the present circumstances of the country and after studying the reality of the economic case for him, as the problem lies with don't selecting the best alternative that enhances the gross domestic product, which extends to promote overall economic development and revive the industrial and agricultural sectors, productivity is more like Impotent, versus sacrifice alternative consumption may bring more financially lucrative than
... Show MoreThe study aimed to identify the reality of the application of cost accounting system in the contracting institutions in Saudi Arabia, and the extent of the reflection of the application of this system on the effectiveness and efficiency of the general performance of these institutions. Where the research community consists of the contracting institutions operating in the Saudi Arabia, and then a suitable random sample was selected from seventy one institutions. The researchers used the historical method to track the previous studies as well as the descriptive approach to conducting the field study. The study data were analyzed by SPSS statistical program.
The results of this study conclude that there is a
... Show MoreThe utilization of recycled brick tile powder as a replacement for conventional filler in the asphalt concrete mix has been studied in this research. This research evaluates the effectiveness of recycled brick tile powder and determines its optimum replacement level. Using recycled brick tile powder is significant from an environmental standpoint as it is a waste product from construction activities. Sixteen asphalt concrete samples were produced, and eight were soaked for a day. Samples contained 5% Bitumen, 2% to 5% brick tile powder, and conventional stone dust filler. The properties of samples were evaluated using the Marshall test. It was observed that the resistance to stiffness and deformation of asphalt concrete
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