KUFA JOURNAL OF ENGINEERING

Drinking water chlorination is one of the most significant advance in public health protection. Besides, chlorine-based disinfectants are the only major disinfectants with the lasting residual properties that prevent microbial regrowth and Provide continual protection throughout distribution system from the treatment plant to the final consumer.In this study it was evaluated the efficiency of the sterilization of drinking water in the water supply network of Kufa city, water samples were taken from seven locations distributed over the city and these samples checked in the morning and evening to identify the concentration of chlorine in all its forms (total residual, free residual and combined) , in addition to the follow up to the concentration of chlorine in the same projects processed water for the city as well as to identify the quantities of doses of chlorine added in these projects. Then the results obtained from the concentration of chlorine were compared with the specifications in order to identify the process of sterilization of water in water projects in the city.

This research is an empirical method for estimating the possibility of using cement dust as an additive for sandy soil during the field compaction process. The soil samples were brought from Al-Najaf city and treated with cement dust .Twenty test models were prepared and compacted in the standard and modified mould of Proctor test. These models were divided into two broad series, firstly consisted of ten soil samples, five from these samples were carried out at constant compactive energy (E=355.5 kJ/m3) for cement dust (4 , 8, 12 and 16%) in addition to one case with no cement dust. This energy is less than standard Proctor test energy. Another retained models were tested with compactive energy equal to the energy of standard Proctor test (E=592.5 kJ/m3) for the same percentage cement dust. The second series of models were involved ten models, five samples compacted at energy corresponding to Modified Proctor Test (E=1197.03 kJ/m3) and other retained models at compactive energy higher than compactive energy of the modified Proctor test (E=2681.4 kJ/m3). The results of laboratory tests which carried out on selected soil showed with increasing compactive energy, the optimum cement dust decreased (this percent was corresponding to the peak dry density in the laboratory) . In other words, the optimum cement dust percents were equal to (4%), (6.6%), (8%) and (12%) for compactive energy (E=355.5, 592.5, 1197.03 and 2681.4 kJ/m3) respectively, and the addition of these percents of cement dust leaded to increase in the maximum dry density (4%, 5.3%, 17.1% and 20.5%) for compactive energy (E=355.5, 592.5, 1197.03 and 2681.4 kJ/m3) respectively.

In this paper an integer programming model was built to obtain an optimal utilization of the available medical resources(human and equipments) in the emergency department in Al-yarmouk hospital. According to model results a plan can be implemented for ministry of health to help the management of al-yarmouk hospital to distribute the available resources in an optimal manner to achieve an optimal medical service to the people who need this medical service.

A nonlinear finite element method is applied to compute the elastic-plastic thermally postbuckling behavior of initially deflected rectangular steel plate under in-plane compression loading. Classical first order shear deformation is assumed using nine-node isoparametric Lagrangian elements to develop the finite element analysis procedure. The geometric and material nonlinearities are included in the present study. Some of effects were studied in the present study such as temperature gradient, initial imperfection, slenderness ratio, and aspect ratio. Based on this study, the main conclusion that the ultimate strength of steel plate depends on the temperature gradient where the ultimate strength will decrease about 11% for slenderness ratio (b/t=120) and about 41% for slenderness ratio (b/t=40) when the temperature increasing from (0.0 oC) to (100oC).

No-fines concrete is a form of lightweight concrete obtained when fine aggregate is omitted. No-fine concrete mainly used for both load bearing and non-load bearing for external walls and partitions and in in-filling panels in framed structures. The essential objective of this work is to investigate the effect of incorporation of polymer (SBR) on the performance of no-fine concrete made from lightweight aggregate (porcelinite) and to suggest possible applications of this type of concrete. Three concrete mixes with different aggregate/cement ratios (A/C) (6:1, 8:1 and 10:1) by volume were selected. Each of these mixes included six mixes which differed in polymer/cement ratios, (0%, 5%, 10%, 15% and 20%) by weight to find the optimum polymer/cement ratio. Density, compressive strength, splitting tensile strength and drying shrinkage were conducted on all concrete mixes. The test results showed that the compressive strength of no-fine lightweight aggregate concrete increased with the increase in polymer/cement ratio up to 15%, and the compressive strength reduced at polymer /cement ratio of 20% . At polymer/cement ratio of 15%, the percentage of increase in compressive strength measured relative to reference mixes was about 50%. On the other hand, the splitting tensile strength was increased with the increase in polymer/cement ratio for all mixes. The percentage of increase in splitting tensile strength compared with reference mixes increased fr0m about 30 to 90% with the increase of polymer/cement ratio fr0m 5 to 20 %. Also the drying shrinkage strains of no-fine concrete decrease, with the increase in polymer/cement ratio. The percentages of decrease in drying shrinkage strain at 56 days were fr0m 5 to 30% with the increase of polymer/cement ratio fr0m 5 to 20%.

In the present work, a model to predict the liquid holdup in slug, two-phase gas-liquid, upwardly flow has been developed. This model has compared with nine published methods by using experimental tests for two types of flow systems available in the literature. The comparison achieved using the relative performance factor (FPR) which is representing an equivalent result of the most statistical tools as: error, average error and standard deviation. The results showed the best performance of the present model than the others for each system of flow separately.

This paper presents a study of the flexural behavior of the reinforced mortar slabs using both of steel fiber concept and ferrocement layer in tension zone cover as an additional reinforcement to the main steel bars .The concept of steel fibers mean that substitution the common types of steel fibers by alternative material exhibit the same action that produced by the tradition fibers. This material represented by short length of steel nails (SLSN) ,which is cheapest and more available than the first type in the local markets .The efficiency of this material have been checked using seven samples of beam prototypes tested under flexural behavior and reinforced with the nails. Results produced that the nails will improve ultimate flexural strength of mortar noticeably .The increasing ratio in flexural strength of mortar was in the range of (400-1200)% related with these seven beams .Therefore, and according to this advantage, eight one way reinforced slab panel have tested under flexural loading. They reinforced with the nails ,one layer of wire mesh to produce ferrocement cover, and the both material . After testing these eight panels ,the once reinforced with SLSN as an additional reinforcement exhibit the best performance in resisting flexural stresses by increasing flexural load capacity from 17.25kN to about 20kN. Furthermore, maximum central deflection was also reduced by this material from 24.75mm for non fiber reinforced panels to 4.9mm for reinforced once. Although the action of ferrocement was less than the results produced by the fibers ,ferrocement cover increases the ultimate flexural load capacity for panels reinforced with single layer of wire mesh as well as decreasing in the maximum central deflection for these panels in comparison with the control specimens .

The study of boundary layer separation control using cylinder based at the leading edge of airfoil NACA 0012 was carried out in this research. The experimental work have been done using wind tunnel with air flow velocity 24 m/s, and with airfoil NACA 0012 at angles of attack (0°, 5°, 10°, 14° and 20°) respectively. The pressure distribution around airfoil NACA 0012 was measured at each above angles of attack to calculate lift and drag coefficients with and without circular cylinder at the leading edge of this airfoil. The visualization of flow around and behind the airfoil NACA 0012 was experimentally produced using smoke wind tunnel at angles of attack(0°, 5°, 10°,14° and 20°) respectively, and repeat the works with circular cylinder at the leading edge of this airfoil at the same angles. The results compared with computational results of other theoretical results researchers, and there is a good approximate between most of results. The angle of separation of the boundary layer of airfoil is 14°, but the angle will be change to 20° when the cylinder be at the leading edge of the airfoil.

The present paper illustrates a type of distance measurement by use an ultrasonic sensor for distance from the foundation of selected points to a frontal object. The sensor was based on the measurement time of travel to an ultrasonic pulse-echo, that was reflected by the object. A controlled technique was use to obtain reflected pulses that were able to detectable by means of a threshold comparator. Such a technique, which takes the frequency response of the ultrasonic transducers into account, allows received pulse detection to be obtained. Experiments performed with a 40 kHz piezoelectric-transducer based sensor, showed a standard stability in laboratory experiment and the sensor still works at motion state by bond the sensor with chair of cripple system. The experimental standard deviation of the linearity with respect to the distance has been found 0.005%. The sensor is composed of only low cost components, thus being equipment in many cases, and is able to adapt to different conditions in order to give the best results.

Bridge pier scouring is a significant problem in the safety estimation of bridges. This research is carried out to study the local scour around the piers of Al-Kufa bridge ,and to estimate the effect of the spacing between the piers on the depth of equilibrium scour . Dimensional analysis technique was used ,and from the collected data filed measurements ,an empirical formula was derived .I has been found that the predicated scour depth from the formula compares well with the observed values . It was found that no mutual influence on maximum scour depth occurs for spacing ratio in Al-Kufa bridge piers , and the scour depth in the middle pier is greater than the others . The study showed that the piers of Al-Kufa bridge is safe against scouring in the present time , However the scour around the piers should be main laned when the hydraulic conditions is change in the location of the bridge.

This study aims to reveal the effect of fire flame on the behavior of glass fiber reinforced mortar slab specimens. The experimental work included casting and testing six of glass fiber reinforced fiber mortar slab specimens with dimensions of (600×600×40)mm. In addition to nine cubes with dimensions of (70×70×70)mm for compressive strength test, and six prisms of (25×25×250)mm dimensions for flexural strength test. The specimens were divided to three series; A1 tested at 25˚C, A2 and A3 subjected to direct fire flame at the lower surface and heated to 500˚C. The burning periods were 30 min and 60 min for A2 and A3 respectively. Based on the results of this work, it was found that the most reduction in compressive and flexural strengths occurs at the first 30 min of burning. The reduction in flexural strength is more pronounced than that in compressive strength. The percentage of residual compressive strength was 76% and 69% and the percentage of residual flexural strength was 60% and 57% for A2 and A3 respectively. In addition, it was found that the deflection increases with the increasing burning time under a certain load. The ultimate load capacity of the reinforced slab specimens decreased with the increase in burning time. The percentage of residual ultimate load was 96% and 94% for A2 and A3 respectively.

The present study is concerned with the behavior of structures made up of I-steel beams in two directions. The grillage or grid framework method as simplified method of analysis is used in this study to study deflection and stresses caused by moments from applied normal loads. A method is suggested to derive the required section rigidities (the flexural and torsional rigidities) of the grillage members. Warping effect was included in the calculation of the torsional rigidities of the grillage members and it was found when warping is prevented the results became approach to the experimental results . Also effect on deflections by transverse shearing forces was found to give more acceptable results in comparison with experimental results.

Using sunshine duration, extraterrestrial radiation and global radiation are used as input parameters in four mathematical models. The daily average diffuse solar radiation in various (16) locations in Iraq have been estimated by using a thirty years solar radiation data within the period from (1961 – 1991). These locations had chosen randomly to cover the most geographic regions of Iraq. The maximum values of diffuse solar radiation are appeared in the summer season which is in range (2 - 9 MJ. m -2 day -1) for (4 models), while the minimum values for solar radiation were in months January and December . These four models are compared between them to estimate the diffuse radiation values for different studied locations over Iraq.

Cement is expected to provide a stabilization agent to the local granular materials used in roads and airports construction as a sub-base coarse. The performance-related properties of granular materials have been studied (with and without cement). The effect of cement addition on the results of CBR test and Atterberg limits determination has been studied. The factors which have been selected in this study include cement content, and the aging time after which the specimen has been tested. The ideal (cement /granular materials) ratio has been found as 6% that is give CBR value more than 100% of the CBR value for granular material only. The increment of CBR value due to the cement addition as 6% on the ESAL repetitions until reach terminal serviceability index ρt=2.5 has been studied according to AASHTO Guide. The cement addition as 6% to the sub-base course increases ESAL repetitions by about 45% greater than sub-base course established fr0m granular materials without cement, within the limitation of this study