KUFA JOURNAL OF ENGINEERING

Drinking water contamination by fluoride component (F-) is considered as a main public problem in Basra city. The current study highlights on the removal of (F-) from drinking water using effective and low cost materials namely, banana shell and new technical that prepared from orange shell loaded with Zirconyl chloride solutions (Z-r4 (O-H)8 (H2-O)16] Cl8 (H2-O)12) to develop active adsorption sites for fluoride . High removal efficiency of 94.4 was achieved using fixed bed column loaded (Zc-dejr) under optimum operating conditions, 15.1 ppm of feed concentration, 4.5 pH of feed solution and 4 cm of bed depth. Result of breakthrough profile showed that Thomas was coincided well with the experimental data. Two model, Pseude first order and Pseudo second order where used for finding the mechanism of adsorption kinetics for fluoride (F-) removal by two-bio adsorbents. The result showed that the external adsorption besides to the intra-particle diffusion contributes to the rate influential step. Lagmaier model gives the better result model for the two adsorbents then Temkin isotherm model (TIM). The final concentration of fluoride in treated water with the banana shell adsorbent was 1 mg/l, and with the new solution (Z-r4 (O-H)8(H2-O)16] Cl8 (H2-O)12 ) was 0.5 mg /l which is acceptable with the standard World Health Organization (WHO).

A Jet erosion tester is designed and used to study the relative erosion behavior of high chromium white cast iron (ASTM 532A) at specific concentration of silica sand as an abrasive material, 45° impact angle and two size of abrasive particles. A slurry pot was used which contains two propellers rotated at the speed required for uniform distribution. The test specimens are mounted on test fixture which is fixed and has a provision to move in different angular position to find out the wear for different angles. Two different experiments are conducted preliminarily by using silica sand as abrasive with particle size of 400-600 µm and 600-800 µm. Impact angle of 45° and solid abrasives of 20% wt. concentration are used as fixed parameters for 10 hours. It was found that the erosion resistance decreases with increasing the abrasive particle size.

The development that has occurred in industries and technologies after the Industrial Renaissance and beyond has led to consume a large amount of raw materials. The huge consumption of these materials is hard to be compensated. Therefore, it is necessary to find materials that can be recycled and environmentally friendly materials. Hence, the idea of sustainability, which states, the ability to meet our current needs without compromising the ability of future generation to meet theirs. It has become an urgent to produce materials that called environmentally friendly or sustainable materials.
In the field of civil engineering, an important role has been played in producing of environmentally friendly concrete by using pozollanic materials. Using environmentally friendly concrete instead of traditional concrete can participate in reducing the effect of global warming. In this research, local materials like metakaolin and pozollanic materials such as, fly ash and grand granulated blast furnace slag GGBFS were used in the production of an environmentally friendly concrete which they are called Geopolymer concrete. The effect of pozzolanic material type and mixing ratios on compressive strength at 7, 28 and 60 days were studied.

In this research paper, the solar irradiance of flat plate solar collector was evaluated using experimental and numerical analysis. In the experiment, an automatic solar simulator was designed and built to simulate the solar irradiance.The simulator was controlled by an Arduino board. The light source and fabrication of the simulator were used for a wide range of testing and the comparison was made between different cases. The test was performed on a flat plate double glazing solar collector with different base fluids; ethylene glycol (EG), glycerine, and water. To enhance the heat transfer, Al2O3 nanoparticles having a diameter of 20 nm were added. In order to investigate the effect of volume fraction on the heat absorption, three-volume fractions, 0.2%, 0.45, and 0.6%, were used in this study. Laminar flow was considered with a flow rate of 1 L/min. Solar irradiance was measured from 11:00 to 13:00 on September 25th, 2016. COMSOL 5.2a was used in a numerical analysis of flat plate solar collector. A good agreement between numerical and experimental for all cases was observed. The maximum temperature difference between inlet and outlet was found when the (water/ Al2O3) was used as a working fluid at a volume fraction of 0.6%.

Tires are considered important components of the vehicle by which the vehicle can move on the road. The continuous development in the transportation requires improving tires to suit the modern requirements of the transportation. This work includes studying the effect of using the pre - tension technique to improve the flexural and adhesion properties of bead ply in rubber tires. Pre-tension levels ranging between (0- 1250 MPa) were applied on each single reinforcing wire at room temperature before the vulcanization process. The results showed that the increasing in maximum bending strength, bending stiffness, and maximum shear strength by (26 %) due to pre-tension. The single fiber pull-out test results show that the debond shear strength was increased by (27 %) pre-tension on steel wires.

In this research, the main aim is to formulate a mathematical model describe the relationship between annual probable maximum precipitation (PMP) for the city of Najaf and other hydrological variables such as temperature, relative humidity and evaporation rates depending on hydrologic data for the period between 1980 to 2005.
All the calculations of the values of annual probable maximum precipitation were made depending on Hershfield's method, which is depended on the general equation of hydrologic frequency analysis and calculating the frequency factor for a group of data. The model was derived by the help of the program (SPSS 21).
The study demonstrated a relative correlation between the previous independent variables, as a group, and the dependent variable (PMP) in one hand and the correlation between each independent variable with the value of PMP in the other hand. The coefficient of determination (R2) obtained from the statistical analysis for four equations were derived for each case with very suitable values.

Specific effects of topography over any area watershed erosion are estimated through the LS factor as the product of slope length L and slope steepness factor S using RUSLE equation. The LS factor map of Euphrates watershed was derived from the raw Digital Elevation Model (DEM) by using of ArcMap 10.2 software, the DEM images were provided from United State Geological Survey (USGS) website. The DEM were consisting of sixteen images with cell resolution of 30m*30m, the DEM of Euphrates watershed is ranged from -100 m to 466 m, 98.83% of Euphrates basin area of DEM within the range 0 to 457 m. The slope in percentage rise map of Euphrates watershed is required to estimate the LS factor, the most of slope of this study was ranged from zero to five which represent about 93.12% from total area of basin. The LS factor of Euphrates basin is ranged from (0) to (8010.61), 94.25% of Euphrates watershed area have the LS factor of the range from (0) to (1). Furthermore, the LS factor values more than 500 of watershed have a small area, so the factor value can be considered up to 500 and neglect the other large values of LS factor. The LS values more than 3 were identified the lines of Euphrates river, distributary channel, rills, interrill and gully.

AN-Najaf city is located 61 meters above the sea level in the dry desert of Iraq. It is one of the most important cities in Iraq due to religious tourism and continuously developing urban areas by constructing multi-storey buildings, bridges and shopping malls. This study aims to create a mapping database for sulfate in An-Najaf soil (Najaf centred and Al-Kufa cities’ soil).To evaluate the spatial variability of data, 464 boreholes and in situ tests were selected and analysed using Geographic Information System ArcGIS 10.2.1. The adopted method consisted of four steps: (1) data collection; (2) geotechnical data georeferencing; (3) interpolation methods and (4) establishment of maps. Nine maps were produced for depths 0-35 m for sulfate content in soil. In addition to two maps for sulfate content in groundwater and organic matter content for depths 0-2. Results showed that all the study area and for depths 0-2 meter has very high sulfate content in the soil. Sulfate values varies between 0.36%- 14% where all the results were higher than the permissible limit which is 0.2%. The sulfate content decreases with the depth yet still effective in some areas. Therefore, precautions have to be adopt to avoid risks. One of the precautions is to use sulfate resistance Portland cement (SRPC) for all concrete works that have contact with soil. Groundwater sulfate content in the study area was ranging between 84-239 %. These values were ineffective because they are lower than the permissible limit, which is 1460%. The organic matter content values vary between 0.05-2.34, the greatest part of the study area was lower than the permissible limit 1% and therefore ineffective. The PH values indicate that all the study area was alkaline so it is uninfluential.

With the development of high resolution sensors in remote sensing satellites, the shadow phenomena has appeared clearly in satellite image. The shadow is a separated feature in the satellite image, some time it may be considered as a problem due to the loss of ray information at the shaded region, other may be considered as a criteria to the height of the body which has a shadow. The length of shadow depends on the height of the body, location on the earth surface, and the sun location in sky at the imaging time. The sun location is varying every hour during the day and every day during year. These varying is calculated by complex astronomic equations. In this article, we simplified these calculations to just on equation depend on one parameter, and examine this equation by field measurements. The suggested equation is sum-sine equation with an enough accuracy to be used in civil, ecological, gardens designing near the high buildings, or architectural purposes. The equation can be used to estimate the building height from the shadow length in the satellite image, as will as it may used to estimate shadow length from the known body height on the earth.

A numerical investigation of steady laminar mixed convection flow of a Copper-water nanofluid in a lid –driven cavity has been executed. In the present study, the left vertical and inclined walls are heated at constant temperature while the right vertical and inclined right walls are maintained at constant cold temperature. The bottom wall is adiabatic and moving with uniform velocity. The study has been carried out for Rayleigh number Ra= 104– 106, Reynolds number Re=20-100 and solid volume fraction of Cu nanoparticles Ø= 0-0.05. The effective viscosity and thermal conductivity of the nanofluid have been calculated by Brinkman and Maxwell-Garnett models, respectively. The results indicated that, the Nusselt number increases with increasing Ra, Re and Ø.

This study has focused on investigation of effect of hydrostatic pressure on the properties of underwater self-compacting concrete. In this research, 30 mixes of self-compacting concrete have been prepared with six groups. The first three groups contain AWA (Anti Washot Admixture), while the second groups made without AWA. The main parameters explored in this research were: silica fume, limestone powder and rice husk ash as a cement replacement content with 0% and 1% anti washout admixture and different water depth (10 ,20, 30 ,40 and 50 m). Washout loss was found by using either the CRD C61 test method or a newly developed device for simulation of increased hydrostatic pressure on the concrete/water interface. Good correlations were investigating between the standard washout loss determined according to CRD C61 and simulated threshold water head and corresponding maximum washout loss.

Type-2iFuzzyilogicicontrol contains footprint of uncertainty (FOUi) that is able to handle the numerical uncertainties, nonlinearities, and linguistic associated with the inputs and outputs. This paper presents the structure of P/PI/PD/PID-like Interval Type-2 Fuzzy Logic Controller (IT2-FLC) that is designed and simulated using MATLAB SIMULINK. This controller is designed by combining the advantages of fuzzy inference and different structures of controller. The type of the controller is selected using two bits control inputs. The inputs to the controller are: input-output gains, set-point, and the actual output. Karnick-Mendel (KM) algorithm is used to implement the IT2-FLC. IT2FLC has two triangular shaped membership functions. The range of the universe of discourse (-1.5 to 1.5) is selected for each input and output. The defuzzification technique is selected as Centroid method. The sampling time is (0.01), and the choice of rules is by using trial and error. The programs are written in MATLAB SIMULINK and converted into VHDL and Verilog languages. The program generated must achieve small FPGA size and as a result less execution time must achieve vs. acceptable accuracy. Linear and nonlinear models were used to test the Controller. Trial and error method was used to tune the gain factors to obtain the best response with minimum overshoot, minimum settling time, minimum Root Mean Squared Error (RMSE), and minimum structure design.

The currently available approaches on the effects of the exposed reinforcement on the flexural strength capacity of beams by other researchers are critically reviewed. These methods for estimating the flexural- compression strengths of beams with main steel exposed along all or part of the span do not give good predictions for the ordinary reinforced member. In this paper, the simple shear-compression theory introduced in earlier study is modified to the treatment of unbonded beams and a very simplistic empirical equation is proposed. The accuracy of the proposed equation is examined by comparing with results of 44 beams from literature. The comparison showed that the predictions by the proposed equation are between 0.85-1.25 to those of test results. The ratio of the experimental ultimate moments to the calculated ultimate moments by the proposed equation gives an average of 1.06 and C.O.V=0.21. The method of calculation proposed here is relatively successful in predicting the ultimate moment resistances but not in predictions of the physical behavior of the beams with exposed reinforcements.

In this research an experimental and computational analysis under Iraqi climate of temperature distribution, velocity and contaminants concentration in the air-conditioned laboratory have been studied for two case studies. Case-I chosen internal combustion engine laboratory of dimensions (10.3 x 8.7 x 3.75) m with a different number of engines used in the experiments and Case-II chosen laboratory of chemical and petroleum products dimensions (3.7x3.6x3.3)m with different locations of the supply air terminal diffuser compared to the existing design situation. ANSYS FLUENT 14 used to simulate the model's laboratories for compared between the present practical work and numerical work results which are acquired by using RNG K-ε and SST k-ω models and found that the SST k-ω model more accurate. The SST (k-w) turbulence model were employed to solve the governing equations numerically with Reynold number 28,933 and validated by comparing the numerical results with experimental data, and this comparison gives a good agreement. The numerical results for case-I compared with experimental data, while for case-II, the numerical results compared with the standard value due to Iraqi cooling code and ASHRAE standards. The results showed that the mixing ventilation system is able to remove various types of pollutants effectively up to 90% in addition to providing human thermal comfort conditions with the effectively of heat removal up to 85% for the state of the internal combustion laboratory. The second case at laboratory of chemical and petroleum products when the supply air terminal diffuser in the same side, the results showed an increase in comfort conditions by up to 40%.Lastly, from the research, it was found that the pollutant transportation and distribution depend in general upon several factors such as type and location of contaminant source, building geometry, the arrangement of air terminal diffuser opening, and thermal/fluid boundary conditions for example flow rate. Numerical simulation of the velocity and diffusion fields in a conventional flow in laboratories is very useful in comprehending flow and diffusion patterns within different changes of the flow conditions.

The present study covers the use of different percentages (25, 50, 75 and 100%) of clay bricks waste as replacement by volume of coarse natural aggregates to produce sustainable self-compacted concrete (SCC). All mixes used containing 10% silica fume as a replacement by cement weight. The properties of SCC studied were, workability, fresh density, dry density, water absorption, compressive strength, splitting tensile strength, flexural strength, modules of elasticity and thermal conductivity. The results show that the flow ability, filing ability, and passing ability of self -compacted concrete through steel reinforcement are decrease with the increase of clay brick waste content. In addition, the segregation resistance decreases with the increase of clay brick waste content of SCC. The use of clay brick waste aggregate causes reduction in density, compressive strength, splitting tensile strength, flexural strength, modules of elasticity and thermal conductivity of SCC. The percentage reduction increases with the increase of clay bricks waste content in self-compacted concrete.