This paper is devoted to investigate the effect of internal curing technique on the properties of self-compacting concrete (SCC). In this study, SCC is produced by using silica fume (SF) as partial replacement by weight of cement with percentage of (5%), sand is partially replaced by volume with saturated fine lightweight aggregate (LWA) which is thermostone chips as internal curing material in three percentages of (5%, 10% and 15%) for SCC, two external curing conditions water and air. The experimental work was divided into three parts: in the first part, the workability tests of fresh SCC were conducted. The second part included conducting compressive strength test and modulus of rupture test at ages of (7, 28 and 90). The third part included the shrinkage test, at ages (7, 14, 21, 28) days. The results show that internally cured SCC has the best workability, and the best properties of hardened concrete which include (compressive strength and modulus of rupture) then the externally cured SCC with both water and air as compared with reference concretes. Also, the hardened properties of internally cured SCC with replacement percentage of (10%) by thermostone chips is the best as compared with that of percentages (5% and 15%) for both external curing conditions. In general, the results of hrinkage test, showed reduction in shrinkage of internally cured SCC as compared with reference concrete.
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The impact of exposure to different sizes of particulate matter (PM1, PM2.5, PM7, and PM10) was evaluated in Babylon concrete plant workers who had been exposed to concrete dust for at least 10 years. The effects of these particles on the hematological parameters, malondialdehyde (MDA) levels, and antioxidant enzymes (catalase and glutathione peroxidase ) were examined. The results exhibited that the levels of PM2.5 and PM10 were higher than the acceptable limits approved by the National Ambient Air Quality Standards (NAAQS). The blood parameters, namely white blood cells (WBC), red blood cell (RBC) and platelets counts, demonstrated non-significant differences between workers exposed to the PM as compared to the control gro
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Recently, many materials have shown that they can be used as alternatives to chemicals materials in order to be used to improve the properties of drilling fluids. Some of these materials are banana peels and corn cobs which both are considered environmentally- friendly materials. The results of the X-ray diffraction examination have proved that the main components of these materials are cellulose and hemicellulose, which contribute greatly to the increasing of the effectiveness of these two materials. Due to their distinct composition, these two materials have improved the rheological properties (plastic viscosity and yield point) and reduced the filtration of the drilling fluids to a large extent. The addition rates used for each o
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The research aims to study the extent of the influence of the dimensions of sensory marketing on the perceptual mental image of customers, knowing the type of relationships that link the dimensions of sensory marketing with each other, no one from the researcher mentioned (as far as the researcher knows) the link between sensory marketing and mental image, from this point of view the main goal is determined, the effect of sensory marketing on the mental image taken from customers, as the research was conducted on a number of first-class restaurants represented (Chef City, Chili House, Mado, Fried Chicken Saj Alreef) and the research community was represented by the customers of the aforementioned restaurants, a
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The present study deals with the experimental investigation of buried concrete pipes. Concrete pipes are buried in loose and dense conditions of gravelly sand soil and subjected to different surface loadings to study the effects of the backfill compaction on the pipe. The experimental investigation was accomplished using full-scale precast unreinforced concrete pipes with 300 mm internal diameter tested in a laboratory soil box test facility set up for this study. Two loading platforms are used namely, uniform loading platform and patch loading platform. The wheel load was simulated through patch loading platform which have dimensions of 254 mm *508 mm, which is used by AASHTO to model the wheel load of a HS20 truck. The pipe-soil system
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