Print ISSN: 1681-6900

Online ISSN: 2412-0758

Volume 31, Issue 8

Volume 31, Issue 8, June 2013, Page 121-1611


Study Shear Strength Characteristics of Gypseous Sandy Soil Using Additives

Hussein H. Karim; T. Schanz; Maha H. Nasif

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1431-1446

The present study investigated the possibility of enhancing collapsible gypseous soil of Al-Qarma site (with relatively high gypsum content around 50%), which is located in Al-Anbar Governorate, using kaolinite and bentonite as additives. The essential idea is concentrated in mixing these additives with natural soil using different percentages (5, 10, 15 and 20% by soil dry weight) to investigate soil shear strength enhancement. The effect of such additives on soil shear strength parameters, cohesion (C) and angle of internal friction (Φ), and their behavior were studied using direct shear test. The results showed that shear strength parameters of soil sometimes increased and then decreased with increasing additives. Generally, higher shear strength parameters have been obtained from bentonite mixed soil than that of kaolinite mixed soil for the same percentages of additives. It was concluded that bentonite was much more effective in increasing C and reducing Φ than kaolinite. While, kaolinite was much more effective in reducing C than bentonite. It was also concluded that gypseous soil shear strength is improved using such additives (with only 5% kaolinite or with only 20% bentonite) which provide cohesion strength to the soil mass and also acts as a binder agent material.

Numerical Simulation of the Infinite Medium of Dry Soil in Dynamic Soil-Structure Interaction Problems

Saad Faik Abbas Al-Wakel

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1447-1458

One of the major issues in the dynamic analysis of soil-structure interaction problems is to model the far field medium. The dynamic analysis of soil-structure interaction problems can be carried out by using a numerical solution procedure such as finite element method. For domains of infinite extension of the soil, using of the standard finite elements method leads to spurious reflections for waves on the artificial boundaries which can seriously affect the results.
This research presents a method based on the mathematical representation of wave propagation to analyze the problems in dynamic soil-structure interaction. In this method, the infinite medium (unbounded domain) of the soil is represented by viscous elements to simulate the radiation damping in the soil. In addition, the material damping of soil is represented by Rayleigh damping and implemented in the bounded domain.
The results obtained from this study indicated that, dissipation in the energy of wave occur due to representing of the infinite medium of the soil by viscous elements and Rayleigh damping. By comparing the results with those obtained from the boundary elements method to simulate the infinite extension of the soil which is proposed by Estorff and Kausel (1989), a good agreement is achieved. In addition, the dynamic response at any depth under the foundation can be estimated by using the present method.

A Study on the Effects of Salt Concentration Environment on theMechanical Properties of Polyester and Composite Materials

Raed Naeem Hwyyin; Azhar Sabah Ameed; Zainab K. Hantoosh

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1459-1473

The study investigates the effects of salt concentration on some mechanical properties of thermoset polyester resin without reinforce and polyester resin reinforced with random fiber glass mat. The volume fraction of the composite material varies in (15%, 25%, 35% and 45%). The two types of material were immersed for (40) days in different salt concentrations ratio (15%, 35% and 55%). The environment consists of salt 99.9% and 0.008% magnesium carbonate and potassium iodide. The study depends on the experimental results of impact test and tensile test to describe the mechanical properties of polyester resin and composite material. It is found that the fracture toughness of composite material increases at approximate ratio of (2.9%) while the polyester resin increases at approximate of (2.25%) due to increasing the salt concentration in water with ratio (40%), so that the fracture toughness increases with approximate ratio (3%) due to increase in the volume fraction ratio from (15%) to (45%). The elastic modulus of composite material increases with ratio of (14.9%) and (90.29%) for polyester due to increase in the salt concentration ratio in the water at approximate ratio of (40%).
The elastic modulus increases at ratio of (13.73%) , the yield stress of polyester increase at ratio (50.32%) and yield stress of composite material increases at ratio (55%) as a results of increase in the volume fraction ratio from (15%) to (45%).

Comparison between Using FLC and Auto-Tuning FLC in Synchronous Generator Transient Voltage Stability Enhancement

Majli Nema Hawas; Abdullah Yaseen Abbas

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1474-1482

This paper compares between responses of Fuzzy Logic Controller (FLC) based exciter and auto-tuning FLC based exciter. Both of the exciters are simulated separately with synchronous generator connected to infinite bus through a short transmission line. The systems where subjected to three phase fault at the infinite bus, maximum Integral of Square Error (ISE) of generator terminal voltage response and critical clearing time were taken as performance indices of the exciters. The systems then studied under normal operating condition to justify the need of auto-tuning.

Interaction of Curves Proposed for Design and Analysis of Hollow Reinforced Concrete Columns

Alaa K. Abdal Karim; Bassman R. Muhammad; Ali S. Rishak

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1483-1496

This Study is aimed to present a simplified approach enable to construction of a new design charts for hollow section reinforced concrete columns subjected to an axial compressive load and uniaxial bending. These design charts can be used directly in the analysis and design of hollow section columns. These charts can be used in design to determine the required amount of steel reinforcing in addition to the required column dimensions, while in the analysis by using these charts; the column load capacity can be estimated.
Two design examples are given to explain the use of the new design charts. It has been shown by these examples that the new proposed charts are very simple to use in structural design applications.

Removal of Ni (Ii) and Cd (Ii) Ions From Aqueous Solutions by Adsorption on to Synthetic Zeolite

Alhassan H. Ismail; Zainab Ali Abd-aljaleel; Ali S. Jaffer

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1497-1507

In this study, the removal of Ni (II) and Cd (II) ions from aqueous solutions using the adsorption process onto synthetic Zeolite has been investigated as a function of initial metal concentration, contact time, pH and temperature. In order to find out the effect of temperature on adsorption, the experiments were conducted at 20, 30, 40, 50 °C and 15, 30, 50 °C for Ni (II) and Cd (II) respectively. Kinetics data show that at higher temperatures, the rate of adsorption on the synthetic Zeolite is much higher compared to that on the lower temperatures. The optimum pH for Ni (II) and Cd (II) removal is found out to be 5.5 and 6 respectively. The batch method has been employed using initial metal concentrations in solution ranging from 25 to 100 mg/l for Ni (II) and from 10 to 25 for Cd (II) at optimum pH. An Atomic Absorption Spectrophotometer was used for measuring the heavy metal concentrations before and after adsorption. Langmuir, Freundlich, models were applied to adsorption equilibrium data to find the best amongst these models. This study has demonstrated that Zeolite was capable to remove 90% of nickel and cadmium from solution of different concentrations. This implies that Zeolite is an important in the removal process. These capabilities of Zeolite could lead to development of a viable and cost effective technology for removal of these pollutants from wastewater for countries like Iraq.

Experimental Comparative Study on the Performance of Single and Multi-Stage Dry Air Filters

Abdul- Kareem R. Abed; Ahmed Q. Ahmed; Ammar F. Khudaier; Thabet C. Yassen

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1508-1520

An experimental study on the effect of filter types, relative humidity and using two stage filters on the weight efficiency and pressure drop across the filter was carried out, to complete the study a test rig is designed and built, the rig consist of three sections air duct, of 30 cm ×30 cm cross sectional area, with overall length of 220 cm. Six types of air filters are used in a single stage filters; namely spongy, polyester, synthetic one and two layer aluminum filters. A molten Aluminum powder dust (Type Aluxite No. 25, 98% less than 35 microns and 2% less than 10 microns) is used. In two stage filters study the bag filter is used as a secondary filter while the primary can be any type of the five filters mentioned above. The study shows that the spongy filters gives a maximum efficiency when is used as a single stage filter as compared with the other filters type. Increasing of working environment relative humidity improves the weight efficiency for both single and two stage filters. Two stage filters can improved the filtration process, it is found that the combination of spongy filter and bag filters give a maximum of weight efficiency of about 92% when the relative humidity equals to 90% . Space distance between two stage filters affect the weight efficiency, it is found that the best distance between the spongy filter and bag filter is between 15 to 20 cm.

Design and Analysis of Knee Ankle Foot Orthosis (KAFO) for Paraplegia Person

Shaker S. Hassan; Khadim K. Resan; Akeel Zeki Mahdi

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1521-1533

Knee ankle foot orthoses (KAFOs) are prescribed to paraplegic patients with low level spinal cord injury and with good control of the trunk muscles. Three types of KAFOs were used in this work (plastic-metal, metal-metal and composite materials), the composite materials were depended on the number of perlon layers (13 layers & 9 layers) with one layer of carbon-fiber and (6 layers) without carbon-fiber. The mechanical properties of most of the KAFOs’ materials were tested by tensile test and fatigue machines.
The data of gait cycle (Ground Reaction Force (GRF), and pressure distribution) were collected from one patient with poliomyelitis (wearing brace type KAFO) and one normal subject. In this paper, the FEM (ANSYS) was used to compute the safety factor of fatigue for all types of KAFOs’ models and the equivalent stress (Von-Mises). The interface pressure between the patient’s leg and the brace was tested by using a piezoelectric sensor.
The results obtained from ANSYS gave the profile of safety factor of fatigue, for metal-metal KAFO (3.69), plastic-metal model (0.88). While, the (13) layers for composite material was about (1.4), but (1.07) & (0.41) for (9) layers and (6) layers, respectively. The value of safety factor increased with the composite material for the suggested design.

Study of Fracture Energy for Plain Concrete by the Use of the Finite Element Method

Abdulameer Q. H

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1534-1542

Failure of plain concrete in tension is characterized by softening, which is accompanied by the development of regions of highly localized strains. The main objective of this research is to study the fracture energy (the value of tensile strain) 〖ε_tu〗^ in the concrete and its effects on the load for plain concrete beams. Beams were tested by Bosco and analysis by the use of computer program ANSYS. The three dimensional brick element was used to represent the concrete element.
The results confirmed that the plain concrete beams do not fail when the first crack is obtain, but depends on the value of the tensile strain 〖〖 ε〗_tu〗^ (fracture energy), where the increase in the value of the tensile strain due to increases in the load applied on the beam.

Water Quality Index for Basrah Water Supply

Risala A. Mohammed

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1543-1555

The water quality index (WQI) is a very effective method that allows to compare the quality of various water samples based on the indicator values of each sample. In this study, water quality index for Basrah water supply was determined by choosing nineteen water treatment plant (WTP) in Basrah city. Twelve chemical and physical parameters of each WTP were analyzed for one year during 2011. The results show that the WQI values of water supply in Basrah city are ranged from 83 to 275. About 10% of water supply can be classified as a good water, 74% can be classified as a poor water and the remaining 16% are very poor water. The prime cause of deterioration in Basrah water quality is the poor quality of the raw source water represented by Shatt al-Arab river, due to the large amount of contaminants are discharged in it. In addition, it is affected by the tide phenomenon of Arab Gulf which causes increase of salts concentrations. Also, the WTPs in Basrah city are conventional type that do not deal with soluble elements. These plants need upgrading by adding filter membranes or ion exchange units, to produce safe water for human consumption.

Kinematic analysis of human climbing up and down stairs at different inclinations

Zahraa M. Abdulhassan; Sadiq J. Abbas

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1556-1566

The purpose of this study is to investigate the kinematics in humans during stair climbing and the influence of stair slope variation on gait cycle .The analysis of biomechanical aspect involved in stair ascent and descent can add to our understanding of the diverse and complicated processes involved in human locomotion and also be useful in the design of private and public environments where stairs are employed. Another application is in the field of gait rehabilitation. A comprehensive movement analysis of stair climbing can support the evaluation of joint replacement or prostheses development. A staircase was developed and designed that allowed the collection of kinematic data for multiple steps at different staircase inclinations. All components are characterized by a robust design which minimizes vibrations. Subjects ascended and descended a four-step staircase at three different inclinations (24°, 30°, and 42°). Kinematics was analyzed by a camera-based optoelectronic system. The data were further processed using kinovea and origin pro.8.5 softwares. Hip, knee and ankle kinematics in sagittal plane during stair ascent and descent were reported. Temporal gait cycle parameters were significantly affected by staircase inclination but Joint angles showed a relatively low but significant dependency on the inclination. This study presents a normative database, which could be used as reference data for assessment of stair locomotion.

Sequencing the Randomly 2D Drawing Entities Using DXF Format

Baraa M.H. Albaghdadi

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1567-1579

The exchange of the data between the drawing programs like this one used in this research, AutoCAD, and the other application programs is very important to develop the applications in CAD systems. The present paper aims to make a logic sequence for the entities that are drawn randomly to prepare them to further CAD or CAM manipulations. The methodology in this work is using the DXF (Data Exchange File) which represents a CAD file format in which the drawing is saved by using AutoCAD package. All the required manipulations, begging from extraction the data of the drawing entities to accomplishment the sequencing, have been done by building a suitable visual basic program. Also, the AutoCAD package has been used as a checking tool for the results after applying the proposed program, by opening the new DXF file format to AutoCAD environment. The results show that the use of the concept of exchanging the data in CAD environment is a good way to apply the methodology of the research.

Pick-interval scallop heightestimation using three types of geometrical end mill cutters on CNC milling machine

Ahmed A.A.Duroobi; Bahha I. Kazem; Bahha I. Kazem; ChenWenlaing

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1580-1600

This research presents the theoretical model, simulation and experimental verification to predict the magnitude of scallop height using 3 and 5-axis milling machine, where the effect of geometrical shape of the workpiece relative to the effect of geometrical shape of the tools had been studied, taking into consideration three different types of milling tools (Ball, Flat and Torus) corresponding to the type of machines that had been used to calculate the scallop height (h) in each point. Also, four different types of surfaces shape (Horizontal, Concave, Inclined and Convex) surface had been utilized to study the effect of these shapes on the value of scallop height. Besides, the effect of cutting direction in each plane had been studied in both types of milling operation (three and five axis milling machine). Finally, the value of stepover had been changed so as to acquaint the effect of this parameter on the magnitude of scallop height on both types of milling operation.
It was established that the scallop height is most influenced by the step over, cutting direction, geometrical shape of the cutter and inclination angle of the plane. The results also show that in 5-axis machining by utilizing different cutters, the angle of inclination of the tool axis was most affects the value of scallop height. It was also concluded that Torus cutter is better than other two cutters (Ball and Flat end mill cutters).

Establishment oF 3D ModelWith Digital Non-Metric Camera in Close Range Photogrammetry

Abbas Z. Khalfa; Imzahim Abdul Kareem Alwan; Aysar Jameel

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 1601-1611

The use of three dimensional computer graphics and visualization techniques is becoming more and more popular, because these techniques visualize more realistic object models than graphic based object models. However, in most application of 3D modeling and visualization, large and complex 3D models data are required. The basic data source of 3D modeling of regular or irregular surfaced objects are known (or calculated) point coordinates. Obtaining 3D model of the irregular surfaced objects need plenty of points to represent the surface exactly. These points can be easily obtained both traditionnal methods and from the measurement of the photographs. the production of 3D object in cloud points dependind on the sampling rate and taking many captures. In this case, an object of face-shaped clay was used and a 3D object is performed with (5563) 3D points with sampling rate (1 mm). The smaller sampling rate results in longer processing and more points. This case could be beneficial in documentation of cultural and historical heritage in a digital library in observing the variation with time.

Production of Digital Map for the Sources of Pollution in Nassiriya Marshes by Using “GIS”

Ali Karem Shaesh; Abbas Jawad Kadhem

Engineering and Technology Journal, 2013, Volume 31, Issue 8, Pages 121-136

Iraqi marshes are one of the most important biodiversity in the world. They had many problems: bad environmental conditions, as well as decreasing of the amount of water that reaches marshes after restoration, in addition to the increase in the source of pollution around the marshes as a result of villages, hospitals, factories ….etc. All these reasons cause dispersion of pollutants in the marshes. This research study the source of pollution such as ( industrial, agricultural, medical, political and waste water) in Nassiriya marshes and project them on the digital maps to generate a final map represents all the sources of pollutants in this region. The research shows the environmental and medical effects of this pollutants and comprising them with the Iraqi environmental legislations.