University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Effect of Graphite Particles Addition on the Wear Resistance and Friction coefficient of Brass Alloy (α)
218
233
EN
Esraa
Abdel-Qader
Maryam
Abdual-Alazim
Baqer
10.30684/etj.27.6.20
This research is devoted to study the effect of different percentage of Graphite<br />particles addition (5,10,15) wt% to Brass alloy (α) produced by stir casting using vortex<br />technique , on the wear resistance and the coefficient of friction under dry sliding<br />conditions using pin-on-disk technique . Three loads (5, 10, 15) N were used at different<br />sliding speeds effect (2.7,3.7,4.7) m/sec . The results showed that the wear rate is<br />increased in general with increasing the applied load , but the composite material<br />reinforced with graphite particles showed wear rate lower than that of the base alloy .The<br />wear resistance of the composite material reinforced with graphite particles with 15 wt%<br />was higher than that of reinforced with 5 wt% . When different sliding speeds were used<br />, the results showed that , the wear rate is decreased with increasing sliding speed .When<br />the coefficients of friction was measured at high loads , It is clear that the composite<br />material has low coefficient of friction as compared with that at low loads , while it is<br />decreased with increasing sliding distance at all used loads , and the composite material<br />reinforced with graphite particles showed remarkable decreasing in temperature when<br />surface temperatures were measured as compared with base alloy.
https://etj.uotechnology.edu.iq/article_30173.html
https://etj.uotechnology.edu.iq/article_30173_04df2d995e44645a844024e06e35e760.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Effect of Current on Average Surface Roughness of Borosilicate Glass at EDM Machining and Comparison with Numerical Programs
1026
1038
EN
Wathik
I. Mahdi
Maan
A. Tawfiq
Shukry
H. Aghdeab
https://doi.org/10.30684/etj.27.6.1
Machining of electrically non-conducting materials like glass is still a major problem. The principle of electric arc was used to generate high electrical discharge (spark) at high currents to machine non-conducting materials at any hardness, which is a new approach.<br />EDM system was build for machining of non-conducting cutting materials such as glass with new technology including the use of powder (graphite) mixed for dielectric solution (tap water) by supplied AC current values (200, 250, 300, 350 and 400A). Voltage of (70V) was used to cut 3mm thickness of borosilicate glass (BSG) to obtain the average surface roughness (Ra) of about (0.003-0.012μm) but the Ra before the machining was (0.005-0.006μm).<br />Numerical program called "Simulent" has been used to investigate the process control for EDM by using GN, BPN, PN and VQN that could predict the Ra with accuracies of 94.236, 94.034, 96.628 and 92.875% respectively from training data sets.<br />The differences on the Ra at different network models for 3mm thickness of BSG never exceed (8%) from testing data sets while the comparison of numerical results with experimental results of Ra among the measured values and prediction various network models, shows a differences between (1-8%).<br />The best predication accuracy is by the use of PN than other network models.
Surface Roughness,EDM,MRR,REW
https://etj.uotechnology.edu.iq/article_29580.html
https://etj.uotechnology.edu.iq/article_29580_57096d5182a46997f01cd88011094093.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Laser sealing and thermal shock resistance of 6.5 wt% yttria Partially stabilized zirconia plasma sprayed layers
1039
1048
EN
Mohammed
Jasim Kadhim
10.30684/etj.27.6.2
Laser sealing of zirconia-6.5 wt% yttria partially stabilized zirconia (YPSZ) plasma<br />sprayed layers were examined for both plan views and transverse sections. Scanning<br />electron microscopy (SEM) has been used extensively to characterize the general features<br />and microstructure of the layers under optimum laser processing conditions. The laser beam<br />is shown to be effective in modified the plasma sprayed layers by sealing the porosity and<br />decrease the roughness. Thermal shock resistance test reveals that sealed layers have been<br />an excellent resistance to cracks formation parallel to the surface.
https://etj.uotechnology.edu.iq/article_29584.html
https://etj.uotechnology.edu.iq/article_29584_b3b26102c5cda0aaa913d197f01356c8.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Simulation of Active Magnetic Bearing Response based NNC
1047
1063
EN
Naseer
Qassim Hamoody
Adil
Hameed Ahmad
10.30684/etj.27.6.3
The present work is dealing with the modeling, investigations, and controlling, of a prototype radial magnetic bearing system. Considerations based on the 8 poles model with switched mode power supply. Investigations of radial forces in two axes model and<br />performance response are carried out through the intelligent controller system.Improving system response is achieved by using an efficient controller based Neural Network (NN) NARMA-L2 Controller together with the conventional PID controller. The response is presented for stand still and dynamic conditions using the implemented Simulink software. The results show that the NARMA-L2 is highly improved the dynamic response of the speeding up rotor in comparison with the conventional controller
https://etj.uotechnology.edu.iq/article_29586.html
https://etj.uotechnology.edu.iq/article_29586_775f17b0281bc06a1bbb762007a79f18.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
HDNA : Heuristic DNA Computing Algorithm
1064
1073
EN
Ahmed
Tariq Sadiq
Hasanen
Samir Abdullah
10.30684/etj.27.6.4
The proposed system is based on embedded the heuristic search in DNA search algorithm so to make it more efficient and flexible. The HDNA system is constructed to improve the work of the DNA computing algorithm and enhance the measurement criteria of it by reducing the run time and the memory capacity as well as the number of generated random solutions (strands or states) that are needed to implement the<br />computing algorithm. The experimental results appear that the HDNA using A* and Alpha-Beta is more efficient than using A* and Alpha-Beta each alone.
DNA Computing,heuristic methods,algorithm,Alpha,Beta Algorithm
https://etj.uotechnology.edu.iq/article_29594.html
https://etj.uotechnology.edu.iq/article_29594_1ce12f9a3619fc9db3d9b27c5281b9c7.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Adiabatic and Separated Flow of R-22 and R-407C in Capillary Tube
1074
1082
EN
Ahmed
Abdulnabi Imran
10.30684/etj.27.6.5
In this paper adiabatic flow in capillary tube is analyzed and modeled for R-22 and<br />alternative R-407C. The equations of continuity, energy and pressure drop through a<br />capillary tube are presented. A mathematical model of sub–cooled flow region and<br />two–phase flow region is developed. The results of the calculation compared with<br />experimental data presented in the technical literature will be shown in the present<br />article in order to validate the model developed. This numerical model is capable of<br />providing an effective means to analyze capillary tube performance to optimize and<br />control an R – 22 and R – 407C in an air – conditioning systems.
Capillary tube,alternative refrigerant,adiabatic flow
https://etj.uotechnology.edu.iq/article_29599.html
https://etj.uotechnology.edu.iq/article_29599_ee383c86ba2076571dd61648470c58a1.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Study of The Optimization Condition Of Batch Sterilization Using Genetic Algorithm
1083
1092
EN
Thamer
J.Mohammed
Chemical Engineering Department, University of Technology /Baghdad
Ittehad
F.Tobia
Chemical Engineering Department, University of Technology /Baghdad
Salah
N.F.Al-Obaidi
Chemical Engineering Department, University of Technology/Baghdad
10.30684/etj.27.6.6
The present work is designed to study the parameters interaction of sterilization<br />processes in batch bioreactors (fermentors of volume 120 liter with medium of 56784 kg).<br />he parameters include the effects of sterilization temperatures (117-126<br />o<br />C), time of<br />heating, time of holding, and time of cooling on removal of all organisms, and degradation<br />degree of medium. Direct steam was used for heating at different temperatures ranged<br />from 120<br />o<br />C to 180<br />o<br />C. The B.Stearothermophilus was selected as the present contaminants.<br />Another bioreactor of volume (56828) liter was studied at 121<br />o<br />C for the same contaminant<br />and compared with actual data.<br />This study is achieved by designed procedure and simulation program useful for<br />the optimization of batch sterilization cycle in large-scale fermentors. The method of<br />optimization used is Genetic Algorithm (GAs) which uses probability to find the optimum<br />condition for the sterilization cycle and to find Del factor; which is the reduction value of<br />initial to final number of microorganisms, and then evaluate the cost which depend on<br />amount of steam consumed in the sterilization processes<br />Graphical relations was indicated that as fermentor size increase, the time of<br />heating also increase. For low temperature the time of holding was increased and for high<br />temperature the time of holding was decreased. Also these relations were investigated the<br />best conditions between holding time and Del factor for degradation at different<br />temperatures.
Batch Sterilization Reactor,genetic algorithm
https://etj.uotechnology.edu.iq/article_29640.html
https://etj.uotechnology.edu.iq/article_29640_69f2aadcac3a18eaea83e518f38ca55b.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Syntheses, Characterization and Study of Use of Manganese (III) Schiff-Base Complex as Thermal Initiation in Radical Polymerization of Styrene
1093
1107
EN
Ahlam
Said Maroof
10.30684/etj.27.6.7
The new schiff base complex: Chloro- (bis (salicylaldehyde) ethylene diiminato)<br />aqua manganese (III) is synthesized and characterized. It is used as thermal initiation in<br />radical polymerization of styrene at 80 c◦ in dark without inhibition and retardation<br />complication, and the rate of polymerization is directly proportional to the squre root of<br />initiator concentration [I]1/2 . gravimetry technique is used for deteremination of the rate<br />polymerization, and viscometery is used for determination of average of polymerization.<br />The uv- visble spectrophotometry is used to determine the rate constant of initiator<br />decomposition (ka). The value of the kinetic parameter ratio kp / kt<br />1/2 (Where kp & kt<br />are the rate constants, propagation and termination respectively).
Thermal Initiation,polystyrene
https://etj.uotechnology.edu.iq/article_30092.html
https://etj.uotechnology.edu.iq/article_30092_1919ac8d3666d596e0ff894f8448b741.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Simulation Study 0f 802.11b DCF Using OPNET Simulator
1108
1117
EN
Mohammad
Hussian Ali
Manal
Kadhim Odah
10.30684/etj.27.6.8
A simulation study of an IEEE 802.11b which is the most important standard for<br />wireless local area networks was presented in this paper. The simulation is conducted using<br />OPNET IT Guru Academic Edition 9.1. Wireless network performance depends mainly on<br />the end to end throughput and average delay. Different applications place different<br />requirements on the network. Thus, it is necessary to evaluate and analysis the performance<br />of IEEE 802.11b WLAN system under the fundamental access mechanism for medium<br />access control (MAC) called distributed coordination function (DCF).This can achieve by<br />studying the impact of parameters such as Request to Send/ Clear to Send (RTS/CTS),<br />Fragmentation Threshold (FTS) and discuss the best configurations and parameters value in<br />correspondence to network load and topology to get best performance which is the main<br />objective of this paper.
Wireless LAN,IEEE,Distributed Coordination Function DCF,Opnet Simulator
https://etj.uotechnology.edu.iq/article_30094.html
https://etj.uotechnology.edu.iq/article_30094_4c5531babbc670ac03cfcb81bc32260c.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Numerical Simulation of a Two-Dimension Ramp Inlet Flow Field
1118
1126
EN
Jalal
M. Jalil
Ahmed
F. Kridy
10.30684/etj.27.6.9
The Two-dimension ramp inlet flow field was studied with typical mode operations.<br />Euler equations were used for solution with no special treatment required. In this work a<br />solution algorithm based on finite difference MacCormack’s technique was developed to<br />solve mixed subsonic-supersonic flow problem through the external shock diffusers<br />(ramp inlet) and it is found to be converge for supercritical and critical inlet operation.
CFD,Supersonic,Ramp Inlet,Shock Capture,MacCormack
https://etj.uotechnology.edu.iq/article_30096.html
https://etj.uotechnology.edu.iq/article_30096_80982a2c1944a8d49a71155e7aa8eb00.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
A Secure Mobile Banking Using Kerberos Protocol
1127
1133
EN
Mohammad
N. Abdullah
May
T. Abdul-Hadi
10.30684/etj.27.6.10
Because the network is an open environment, a lot of care must be taken when<br />transferring sensitive information especially when related with financial data. This depends<br />on the principals to be trusted which is a problematic and since the first step in network<br />security is the authentication, this paper presents a proposed modal for secure mobile<br />banking (m-banking) applications using Kerberos (the network authentication protocol).<br />The aim of this paper is to establish a secure communication between the clients and<br />mobile-bank application server in which they can use their mobile phone to securely access<br />their bank accounts, make and receive payments, and check their balances.<br />The integration of smart card into classic Kerberos enhances the security for client<br />authentication by storing the cryptographic keys and perform dual factor authentication.<br />Other enhancement to Kerberos is the PKINIT in which the shared key is mapped with<br />public- private key. To build a robust client authentication the client uses his/her mobile<br />phone to author Kerberos's messages, process the replay and establish secure<br />communication with the application server.
authentication,bank,mobile,Kerberos,PKINIT,smart card,ClientServer,shared key,public,private key,Cryptographic,applet
https://etj.uotechnology.edu.iq/article_30101.html
https://etj.uotechnology.edu.iq/article_30101_7bbad0a9313c3f6c155d04bd184bc770.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
The Effect of Surfactant Concentration on the Rate of CO2 Absorption by Carbonate Solution in Packed Tower
1134
1142
EN
Fadil
H. Faraj
Alyaa
K. Mageed
10.30684/etj.27.6.11
Absorption of carbon dioxide from gaseous mixture (carbon dioxide, air) was<br />studied by using Carbonate Solution (Na2CO3) in a counter-current packed column (7.5 cm<br />id, 1.70 m height), packed with glass rashing rings of 1.8 cm i.d to a depth of 1.1 m.<br />The effect of Surfactant concentration (dodecyl benzene sulfuric acid sodium<br />(DBS))(0.5, 1.5, 2.5gm/lit.), gas mass flux (0.05, 0.075, 0.1 kg/m2.sec) and liquid mass flux<br />(kg/m2.sec) on the absorption rate of carbon dioxide and mass transfer coefficient was<br />studied at constant carbonate concentration (0.3 kmol/m3), inlet carbon dioxide<br />concentration(0.08, Y2=0.086 mol CO2/mol air), ambient temperature and atmospheric<br />pressure. The results show that the absorption rate tends to increase with increasing gas and<br />liquid flow rate. Mass transfer coefficient (KG.a) increases with increasing liquid flow rate<br />and slightly change with increasing gas flow rate. Increasing surfactant concentration<br />(decreasing surface tension) leads to decrease the absorption rate and mass transfer<br />coefficient.
surfactant,Absorption with chemical reaction,carbon dioxide,Carbonate Solution,Mass transfer coefficient
https://etj.uotechnology.edu.iq/article_30104.html
https://etj.uotechnology.edu.iq/article_30104_376e6aec5e894d1737b7d73f84d010d3.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Using of Taguchi Method to Optimize the Casting of Al–Si /Al2O3 Composites
1143
1150
EN
Osama
S. Muhammed
Haitham
R. Saleh
Hussam
L. Alwan
10.30684/etj.27.6.12
Taguchi method is a problem – solving tool which can improve the performance<br />of the product, process design and system. This method combines the experimental and<br />analytical concepts to determine the most influential parameter on the result response for<br />the significant improvement in the overall performance. In this research Al–Si /Al2O3<br />composites was prepared by vortex technique using three different parameters, stirring<br />time, stirring speed, and volume fraction of the reinforcement particles. A tensile and<br />hardness tests were done for the resulted castings. The primary objective is to use<br />Taguchi method for predicting the better parameters that give the highest tensile strength<br />and hardness to the castings, and then preparing composites at these parameters and<br />comparing them with the randomly used once. The experimental and analytical results<br />showed that the Taguchi method was successful in predicting the parameters that give<br />the highest properties and the volume fraction was the most influential parameter on the<br />tensile strength and hardness results of castings
composites,Taguchi method,Tensile Strength,Hardness
https://etj.uotechnology.edu.iq/article_30107.html
https://etj.uotechnology.edu.iq/article_30107_f56c137431a2841021389f79953711e3.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Effect of Laser Surface Treatment on Wear Resistance of 100Cr6 Steel
1151
1161
EN
Khansaa
Dawood Salman
https://doi.org/10.30684/etj.27.6.13
The effect of laser surface heat treatment on wear resistance of 100Cr6 steel was<br />investigated. In this work, 100Cr6 steel which is widely used in many industrial of automobiles<br />hardened by using Nd: glass laser (l=1.060mm, t=300ms). Three different laser energies have been<br />used to perform hardening (0.3, 0.58 and 0.93 Joule). A pin-on-disc technique has been used to<br />evaluate wear rate of the specimens as-received and specimens treated by Nd: glass laser at<br />different applied loads and different sliding speeds with 420 r.p.m and 45 HRC of rotating<br />disc. The results show that the wear rate increases with increasing applied load and decreases with<br />increasing sliding speed, wear rate for laser energy 0.93 J less than another energies 0.3 and 0.5 J.<br />Also the microhardness decreases with increasing in depth of hardening, and the microhardness<br />for laser energy 0.93 J more than another energies for the same depth.
Wear Resistance,glass laser,Microhardness
https://etj.uotechnology.edu.iq/article_30112.html
https://etj.uotechnology.edu.iq/article_30112_22567166e3a51bb810f161973dd4fcf8.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Video Image for Security System by Using Chaotic Oscillator for Segmentation
1162
1173
EN
Emad
Kadum Jabbar Alfatly
Nuha
Jameel Ibrahim
10.30684/etj.27.6.14
There are wide variety of mechanisms available for performing the authentication<br />function. One of them is by using video film to monitor important places. In such systems<br />the important task is recognizing human faces which need good segmentation and high<br />feature extraction. In traditional technique the segmentation can be performed by region<br />growing and shrinking, clustering method, and boundary detection which all take image<br />pixel by pixel and compare each with neighbors to get the similarity. Chaotic oscillator<br />depends on synchronization concept between points to determine the active points which<br />construct similar region determining the object. Then RGB color space is used to determine<br />skin color pixel. Skin color model aids the process of separating the face from the scene due<br />to its skin color. After isolating the human face image which contains many features (eye,<br />eyebrow, nose, etc...) they identify the person. Chaotic oscillator is used to extract the<br />important features by removing any point that is not synchronized with its neighbors and<br />gives new image which contains only the main face features and then compare this image<br />with stored image in Database of authorized person and make decision on if (he/she) is an<br />authenticated image or not.
Chaotic Oscillator Segmentation,Face detection,Skin color segmentation
https://etj.uotechnology.edu.iq/article_30116.html
https://etj.uotechnology.edu.iq/article_30116_c029c413d8cdfb2ced833485556db578.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Correlation between Thickness, Grain Size and Optical Band Gap of CdI2 Film
1174
1183
EN
Modaffer
A. Mohammed
10.30684/etj.27.6.15
Structural and optical property was studied as a function of film thickness for<br />thermally evaporated CdI2 films. Stoichiometric films (up to 250 nm thickness) showing<br />hexagonal structure, and good c-axis alignment normal to glass substrate plane. The<br />optical absorption data indicate an allowed direct inter – band transition near the<br />absorption edge with optical energy gap varies continuously from 2.9 eV to 3.6 eV.Part<br />of the optical data was fitted to an indirect type transition to determine the indirect optical<br />energy gap which also varies continuously from 2.2 eV to 3.1 eV . Both energy gaps<br />show thickness dependences, which can be explained qualitatively by a thickness<br />dependence of the grain size through the decreasing of the grain boundary barrier height<br />with grain size.
CdI,Optical Band,gap
https://etj.uotechnology.edu.iq/article_30118.html
https://etj.uotechnology.edu.iq/article_30118_6c68ecbd01427b2ffc56b683573fd09f.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Data Hiding in Sound Using Time Modulation of Unvoiced Blocks
1184
1196
EN
Hilal
H. Saleh
Loay
A. Jorj
Nidaa
F.Hassan
10.30684/etj.27.6.16
This paper is concerned with hiding secret data in audio media file (.WAV). When<br />performing data hiding in audio, one must exploit the weaknesses of Human Auditory System<br />(HAS), while at the same time being a ware of the extreme sensitivity of this system. This<br />hiding method is oriented to embed the secret data such that it is capable of surviving against<br />modifications produced by MP3 compression standard. Statistical and analytical<br />investigations are performed to assess the variations which may occur in the WAVE audio<br />when it is subjected to MP3 compression. Features of speech signal are exploited (Voiced-<br />Unvoiced segments) for embedding the secret data. Hiding is attempt by shortening or<br />elongating the unvoiced blocks of audio file (cover) data. To support the immunity of the<br />proposed hiding system, an encryption method is added to the proposed hiding system.
Audio Hiding,Speech Analysis methods,Audio compression
https://etj.uotechnology.edu.iq/article_30121.html
https://etj.uotechnology.edu.iq/article_30121_7c7d03a3ef5c049dd8c4eb1e492b94f0.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Studing The Mechanical Properties And Morphology of Ternary Blends Of Polyethylene
1197
1205
EN
Nabeela
A. Mohammed
10.30684/etj.27.6.17
The mechanical properties and the morphology of the ternary blend of<br />LDPE/LLDPE/HDPE were studied.<br />In the present work LDPE was mixed with equal amount of LLDPE and different<br />wt% of HDPE (0, 10, 20 and 30 %) using the two roll mills. The mechanical properties<br />and the morphology were specified by measuring the (tensile, hardness, impact<br />properties) for the former, and photomicrograph for the later. From the tensile test<br />results it was found that the tensile strength at break of the ternary blend increased with<br />increasing the HDPE contain also the increases of wt% HDPE leads to decrease the<br />elongation at break. For the hardness test it was found that the shore hardness of the<br />ternary blends increased with the increasing the HDPE contain .On the other hand the<br />impact test carried out also and it was found that the addition of HDPE leads to<br />decrease the impact strength . Nevertheless, optical micrograph results that the HDPE<br />serves as a compatabilizing agent for immiscible LDPE/LLDPE
ternary blends LDPE,Mechanical properties
https://etj.uotechnology.edu.iq/article_30126.html
https://etj.uotechnology.edu.iq/article_30126_a90125c0674c1b709ea71ce108cc7c26.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
A Data Base for Self-Compacting Concrete in Iraq
1206
1218
EN
Shakir
A. Al-Mishhadani
Mays
F. Al-Rubaie
10.30684/etj.27.6.18
Self-Compacting Concrete is considered one of most remarkable developments in<br />concrete technology. It is a new type of high performance concrete with the ability of<br />flowing under its own weight and without the need of vibrations. Recently, a great native<br />interest had been derived towards self-compacting concrete.<br />This work aims to present a summary study about properties of fresh selfcompacting<br />concrete depending on the results obtained by some native researches, thus<br />focusing on the main common features between their results. It had been focused on the<br />effect of type and proportions of constituent materials incorporated in producing selfcompacting<br />concrete. This considered the most influential factors in controlling its<br />properties.
Iraqi self,Compacting Concrete,properties of fresh self,materials of self
https://etj.uotechnology.edu.iq/article_30135.html
https://etj.uotechnology.edu.iq/article_30135_d033784e8c95a7821ce93902d73c2d2d.pdf
University of Technology-Iraq
Engineering and Technology Journal
1681-6900
2412-0758
27
6
2009
04
01
Behavior of Short Reinforced Porcelinite Concrete Columns Under Concentric Loads
1219
1233
EN
Kaiss
F. Sarsam
Ihsan
A. S. Al-Shaarbaf
Mustafa
S. Shuber
10.30684/etj.27.6.19
This study presents on experimental method to investigate the behavior of<br />reinforced porcelinite concrete columns subjected to concentric load. The experimental<br />work includes investigation of ten lightweight concrete columns with square cross<br />section 190×190mm and 1000mm in length subjected to concentric load to assess the<br />effect of the amount of longitudinal steel reinforcement, lateral tie reinforcement and<br />grade of concrete. From the experimental observation it was found that the porcelinite<br />aggregate is a good structural material to produce lightweight concrete columns. It is<br />noted from tested columns that keeping the amount of the longitudinal steel ratio<br />constant, the increase in the amount of transverse steel to about four times (by<br />decreasing the spacing to about a quarter according to the ACI-Code (318M-05)) gave a<br />significant influence on column post-cracking behavior. The improvements in the<br />column due to higher value of confinement include: (i) less brittle behavior; (ii)<br />significantly less damage to the concrete core; (iii) 12% increase in column load<br />carrying capacity. Also, A modified formula for column capacity is proposed to take<br />into account the influence of spacing of ties (effect of confinement).
Porcelinite,columns
https://etj.uotechnology.edu.iq/article_30161.html
https://etj.uotechnology.edu.iq/article_30161_7621283557de2e0372bc18594ada6375.pdf