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 group. However, differentiated white blood cells count revealed a significant increase of polymorphonuclear leukocytes (PMN) in exposed workers in comparison with the control group. However, both MDA and glutathione peroxidase showed a highly significant increase in the workers ass compared to the control group. Thus, we may conclude that the concrete plant workers are exposed to a higher risk of oxidative stress that could lead to alterations in hematological parameters, enzymatic activities, and MDA level.
This paper presents experimental results regarding the behaviours of eight simply supported partially prestressed concrete beams with internally unbonded tendons, focusing particularly on the effect of three different variables: concrete compressive strength,
This research is concerned to investigate the behavior of reinforced concrete (RC) deep beams strengthened with carbon fiber reinforced polymer (CFRP) strips. The experimental part of this research is carried out by testing seven RC deep beams having the same dimensions and steel reinforcement which have been divided into two groups according to the strengthening schemes. Group one was consisted of three deep beams strengthened with vertical U-wrapped CFRP strips. While, Group two was consisted of three deep beams strengthened with inclined CFRP strips oriented by 45o with the longitudinal axis of the beam. The remaining beam is kept unstrengthening as a reference beam. For each group, the variable considered
... Show MoreTo accommodate utilities in buildings, different sizes of openings are provided in the web of reinforced concrete deep beams, which cause reductions in the beam strength and stiffness. This paper aims to investigate experimentally and numerically the effectiveness of using carbon fiber reinforced polymer (CFRP) strips, as a strengthening technique, to externally strengthen reinforced concrete continuous deep beams (RCCDBs) with large openings. The experimental work included testing three RCCDBs under five-point bending. A reference specimen was prepared without openings to explore the reductions in strength and stiffness after providing large openings. Openings were created symmetrically at the center of spans of the other specimens
... Show MoreNon-prismatic reinforced concrete (RC) beams are widely used for various practical purposes, including enhancing architectural aesthetics and increasing the overall thickness in the support area above the column, which gives high assurance to services that this will not result in the distortion of construction features and can reduce heights. The hollow sections (recess) can also be used for the maintenance of large structural sections and the safe passage of utility lines of water, gas, telecommunications, electricity, etc. They are generally used in large and complex civil engineering works like bridges. This study conducted a numerical study using the commercial finite element software ANSYS version 15 for analysing RC beams, hol
... Show MoreThe incorporation of recycled concrete aggregate (RCA) into asphalt concrete supports circular economy goals by reducing reliance on virgin materials and minimizing construction waste. However, RCA’s inherent limitations, such as high porosity, microcracking, and poor interfacial bonding, compromise the structural integrity and durability of asphalt mixtures. This study introduces sugarcane molasses (SCM), a naturally derived, carbohydrate-rich byproduct of sugarcane refining, as a novel and eco-friendly surface treatment for RCA aimed at enhancing its compatibility with asphalt binders. SCM was applied at 5-6% by weight of RCA replacing coarse aggregate at varying levels (0-100%) to assess its effect on asphalt mixture performance. A com
... Show MoreThe purpose of this paper is to present an approach to compute accurately the distributions of the frictional heat generated, contact pressure and thermal stresses at any instant during the sliding period (heating phase) of the single-disc friction clutch system works in the dry condition and the complex interaction among them.
Numerical work was achieved using the developed elastic and thermal finite element models (axisymmetric models) to simulate the engagement of the single-disc friction clutch system.
This paper presents numerical and experimental stress analyses to evaluate the contact and bending stresses on the teeth of spiral bevel gear drive. Finite Element Method has been adopted as a numerical technique which accomplished basically by using ANSYS software package. The experimental stress analysis has been achieved by using a gear tooth model made of Castolite material which has photoelastic properties. The main goal of this research is detecting the maximum tooth stresses to avoid the severe areas that caused tooth failure and to increase the working life for this type of gear drives.
1-Identifying the intellectual exertions have basic education faculty professors.
2-. Identifying the differences in intellectual exertions as a variable type (male-female) current research society is determined by the basic education college professors and both sexes Mustansiriyah University and academic year (2018-2019) and sample (200) textbook and teaching staff researcher has built a scale term This intellectual and extract his results showed statistical characteristics:-. The College of basic education teachers suffer from stress. There were no differences between males and females in intellectual exertions. Depending on the results, the researcher has developed a number of recommendations and
... Show MoreThis study aimed to investigate the incorporation of recycled waste compact discs (WCDs) powder in concrete mixes to replace the fine aggregate by 5%, 10%, 15% and 20%. Compared to the reference concrete mix, results revealed that using WCDs powder in concrete mixes improved the workability and the dry density. The results demonstrated that the compressive, flexural, and split tensile strengths values for the WCDs-modified concrete mixes showed tendency to increase above the reference mix. However, at 28 days curing age, the strengths values for WCDs-modified concrete mixes were comparable to those for the reference mix. The leaching test revealed that none of the WCDs constituents was detected in the leachant after 180 days. The
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