Print ISSN: 1681-6900

Online ISSN: 2412-0758

Volume 36, Issue 2A

Volume 36, Issue 2A, February 2018


Workability of Hybrid Fiber Reinforced Self-Compacting Concrete

Tareq S. Al-Attar; Samer F. Daoud; Anmar S. Dhaher

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 111-116
DOI: 10.30684/etj.36.2A.1

The aim of this work is to evaluate the effect of adding different types of fibers on the fresh properties of the self-compacting concrete, SCC. The used types of fibers were steel (with volume ratios of 0.75, 1.0 and 1.25 %) and polypropylene fibers (0.10 and 0.15 %) and a hybrid system of these fibers (0.65 % steel and 0.10 % polypropylene). The conducted tests in the fresh state were slump flow, T500, V-funnel and L-box. It was noticed that increasing the volume fraction of fibers would lead to decrease in the workability of SCC. According to EFNARC requirements for SCC, many test results were nonconforming. It was also concluded that polypropylene fibers have higher detrimental effect on fresh properties of SCC than steel fibers and that was attributed to the ability of polypropylene to absorb part of mixing water.

Relationships between Actual Compressive Strength, Modulus of Elasticity and Non-Destructive Tests of High Strength Concrete

Jasim M. Abd

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 117-124
DOI: 10.30684/etj.36.2A.2

The present research investigate with Nondestructive testing (NDT) of high strength concrete (HSC). An experiential work was carried out including both destructive and nondestructive test methods utilized to various concrete mixes with compressive strength ranged from 44 to 84.4MPa.Correlation curves were derived as pulse velocity and modulus of elasticity vs. compressive strength for high strength concrete. Two empirical relations were proposed for foretelling the modulus of elasticity Ec = 0.4141f`c + 8.6077, and compressive strengths fcu = 320.85ln (V) – 467.73 with a good coefficient of determination R2 for these equations 0.94and 0.90 respectively. Obtained from cubic and cylinders using locally available materials, therefore; it has been observed that NDT is rationally good and credible tool to measure the property of concrete and gives acceptable indication of the compressive strength development. Comparisons with the ACI 318 and the ACI 363 empirical equations for the prediction of the modulus of elasticity were performed. It was observed that the ACI 363 equation underestimates the modulus of elasticity, while the ACI 318 equation overestimates.

Shear Strength of Concrete Deep Beam Subjected to Uniformly Distributed Load

Eyad K. Sayhood; Ali S. Resheq; Ayad J. Habeeb

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 125-135
DOI: 10.30684/etj.36.2A.3

In this paper, result of tests on 20 simply supported concrete deep beams are presented. All tested beams have dimensions of (150 x 400 x 1100) mm and tested under (1, 2, 4 and 8) point loads. The considered parameters are shear span to effective depth ratio (a/d), concrete compressive strength (fʹc) and longitudinal reinforcement ratio (ρw).The influence of these parameters on cracking and ultimate load, load versus deflection response and concrete strain are investigated.
The results showed that the decrease in the (a/d) ratio from 1.373 to 0.412 leads to a decrease in cracking and ultimate shear strengths by average ratios of 40 % and 57 % respectively, while increasing (fʹc) and (ρw) leads to the increase in the cracking and ultimate shear strengths. The load-deflection response is significantly affected by the (a/d) ratio and becomes appreciably nonlinear as the (a/d) ratio increases, while it is slightly affected by the compressive strength of concrete (fʹc) and steel ratio (ρw). Strain distribution through the depth at mid span is nonlinear even in elastic stage. At the same load level, strain distribution increases as (a/d) increases and decreases as (fʹc) and (ρw) increase. The analytical work has been made on the 20 deep beams plus 62 from literature using the regression analysis. Proposed equation was compared with four equations available in literature and gave less average and coefficient of variation equal to1.04 and 16.98% respectively.

Robust Visual Lips Feature Extraction Method for Improved Visual Speech Recognition System

Mahmuod H. Mahmmed; Thamir R. Saeed; Wissam Ali

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 136-145
DOI: 10.30684/etj.36.2A.4

Recently, automatic lips reading ALR acquired a significant interest among many researchers due to its adoption in many applications. One such application is in speech recognition system in noisy environment, where visual cue that contain some integral information added to the audio signal, as well as the way that person merges audio-visual stimulus to identify utterance. The unsolved part of this problem is the utterance classification using only the visual cues without the availability of acoustic signal of the talker's speech. By taking into considerations a set of frames from recorded video for a person uttering a word; a robust image processing technique is used to isolate the lips region, then suitable features are extracted that represent the mouth shape variation during speech. These features are used by the classification stage to identify the uttered word. This paper is solve this problem by introducing a new segmentation technique to isolate the lips region together with a set of visual features base on the extracted lips boundary which able to perform lips reading with significant result. A special laboratory is designed to collect the utterance of twenty six English letters from a multiple speakers which are adopted in this paper (UOTEletters corpus). Moreover; two type of classifier (using Numeral Virtual generalization (NVG) RAM and K nearest neighborhood KNN) where adopted to identify the talker’s utterance. The recognition performance for the input visual utterance when using NVG RAM is 94.679%, which is utilized for the first time in this work. While; 92.628% when KNN is utilize.

Parametric Study on Intrinsic Reaction for Straight Run Heavy Naphtha Hydrodesulfurization over CoMo/Al2O3 Catalyst

Mohammad F. Abid; Mohammed K. Abdullah; Salah M. Ali

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 146-153
DOI: 10.30684/etj.36.2A.5

The present study aimed to investigate the intrinsic reaction of hydrodesulfurization (HDS) for a real Straight Run Heavy Naphtha (SRHN) over CoMo-S/Al2O3 catalyst in a fixed- bed reactor. Influence of the process parameters on sulfur removal was investigated by regulating the temperature (T = 320-380 oC), pressure (P = 20 to 35 bar), weight hour space velocity (WHSV = 2.5 to 5.0 h-1) and catalyst average particle size (dp =361 to 3950 μm). Mears and Weisz-Prater criteria were estimated and utilized to validate the intrinsic reaction condition. Operating variables were optimized at (T = 360 oC, P = 30 bars, WHSV = 2.5 h-1, dp= 361 μm) to obtain an optimum sulfur removal of 93.4% under intrinsic reaction conditions. Experimental results showed that % activity of sulfur removal increases to 93.4% as temperature increased to 360oC but it reduces to 90.3% as space velocity increased to 5.0 h-1. Kinetic parameters of the intrinsic reaction rate were estimated and compared with published data. Long-time test was performed on the sulfided catalyst to investigate its activity.

Experimental Behavior of Self Compacting Concrete Corbels Strengthened with External CFRP

Sarmad Sh. Abdulqader; Basil Salah Al-Shathr; Ali Kh. Hasan

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 154-162
DOI: 10.30684/etj.36.2A.6

This research aims to study the influence of using Carbon Fiber Reinforced Polymer (CFRP) strips as an external strengthened and repairing material on the behavior of self-compacting concrete (SCC) Corbels. The experimental work involved testing twenty self-compacting concrete corbels specimens. The experimental work is divided into two parts; the first part consists of three groups to investigate the most effective direction, position, bonding type and amount of CFRP strips on the behavior of corbels and utilized it in practice, also to strengthen new variables that are investigated in the second part. Two groups in part one are strengthened with different numbers of inclined and horizontal direction of CFRP strips, while in the third group the specimens were strengthened with strips of CFRP having different directions and bond types to improve the strength capacity and behavior of corbels. This improvement is represented by increase cracking load by about (94)% and increase in their ultimate load capacity of strengthening corbels which varies from about (19 to 88)%. While the second part of experimental work included the following variables: shear span to effective depth ratio (a/d), amount of horizontal steel reinforcement stirrups and repaired damaged corbels. The reinforced concrete corbels in this part were strengthened and repaired by CFRP strips depending on optimum result that is produced from part one wherefrom position, direction and amount are considered. It was found for un-strengthened and strengthened corbels having same horizontal secondary reinforcement stirrups that when (a/d) ratio decreases from 0.65 to 0.4 causes increase in cracking and ultimate loads reach (55)% and (35.41)% respectively. For un-strengthened and strengthened corbels having same (a/d) ratio, it was found an increase in cracking load which varies from (6.66 to 34.78)% and from (18.18 to 52.63) % in ultimate load when horizontal secondary reinforcement stirrups are increased. It was also found repairing SCC corbels with CFRP strips causes an increase in ultimate load reaching up to (50)% with respect to un-strengthened specimens. From results it is concluded that strengthened or repaired corbels present stiffer load deflection response than corresponding un-strengthened corbel (control corbel).

Experimental Behavior of Hybrid Steel and Polypropylene Fiber Reinforced Concrete Deep Beam Containing Openings

Nabeel Al-Bayati; Noor Hadi

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 163-171
DOI: 10.30684/etj.36.2A.7

Twelve simple span reinforced concrete deep beams were tested under symmetrically two points top load to examine the effect of steel fiber and polypropylene fiber and influence of the transverse circular openings on their behavior. The variables investigated involve beams with and without openings, the volume fraction of fibers, shear span to effective ratio a/d, and inclined reinforcement around the openings. All the beams had the same overall dimensions, flexural reinforcement and opening size. Many mixes have been used by combination between steel fibers and polypropylene fibers with different percentages of (1%SF-0%PPF), (0.75%SF-0.25%PPF), (0.5%SF-0.5%PPF), (0.25%SF-0.75%PPF), (0%SF-1%PPF) in addition to mix without fibers. The test results showed that fibers greatly increase the diagonal cracking strength and shear strength of reinforced concrete deep beams, where the variation of the type of concrete from normal concrete to hybrid concrete for deep beam contains openings led to increase the ultimate strength by about 30%. In addition, it was found that the shear capacity of deep beams increased when the shear-span/effective depth ratio decreased. The inclined reinforcement around the opening was observed to be very efficient in improving the ultimate load capacity and deflection response.

Design and Analysis of American Sign Language Classifier Based on n-tuple Technique

Mahmuod AL-Muifraje; Thamir Saeed; Mosab A. Hassan

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 172-178
DOI: 10.30684/etj.36.2A.8

This work consists of three stages: the first stage is the collection of data (images) for 26 letters alphabet, which is 1040 images, 40 for each class (letter). The second stage is the Preprocessing (segmentation, filtering, crop, convert to a binary image and feature extraction) and the last stage is the classy one. Two filters have been used median and wiener2 to treatment two types of noise; the salt and pepper and Gaussian noise respectively. The classification has been satisfied by using an n-tuple classifier algorithm is 93.8462%, while it is 93.2692% with salt and pepper noise. In this context, the recognition is 94.2308% when the median filter is used for salt & Pepper noise, while, it is 93.8462% when to use a Wiener2 filter with Gaussian noise. The optimal tuple size is 4, and suitable training pattern is 40 per each class.

Experimental Study for the Effects of Crystalline Agents on Properties of Glass-Ceramic Coating

Ibtihal A. Mhmood; Ahmed A. Zainulabdeen; Jabbar H. Mohmmed

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 179-184
DOI: 10.30684/etj.36.2A.9

In this work, four series of glass-ceramic coatings were developed and applied by using the dipping technique to cast iron sheets. The influence of different types of crystallization agents (Li2O, TiO2, ZrSiO4, and CaO.Al2O3.2SiO2) was investigated in relation to the mechanical features of the coatings. The resultant coating is characterized using X-ray diffraction analysis. The properties of micro-hardness and adhesion strength are evaluated using suitable standard tests. The X-ray analysis of resultant coatings showed the existence of some of crystalline phases formed depending on the type of the crystallization agent. The results also indicated that the coating properties were strongly dependent on composition and concentration of crystallization agent. Coating with feldspar gives the highest value of hardness and adhesion index. In general, properties of the resultant coatings were improved in all cases; this is related to the formation of a complicated network from crystalline phases.

Frequency Reconfigurable Monopole Antenna Using Switchable Slotted Triangular Radiators

Fayyadh H. Ahmed; Bayez K. Al-Sulaifanie

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 185-195
DOI: 10.30684/etj.36.2A.10

A new configuration of multi-state switchable wideband /multi-narrowband is demonstrated. The proposed antenna is based on a printed rectangular monopole antenna (PRMA) that covers wideband 3.3 GHz WiMAX frequency range. To generate a multi-state switchable antenna, center part of PRMA has been removed without distorting the PRMA behavior. Three PIN diode switches are used to control different operating modes. Eight-operating modes, 2n modes (n is number of switches) are achieved by setting the switches ON or OFF. Initial results were obtained by using short and open circuits instead of implanting PIN diode. The merit of the antenna design is that it allows various groups of its operating frequency bands to be selected using different switches states. Therefore, by selecting different antenna modes, a variety of communication systems can be conveniently served by only one antenna. The designed antenna has a simple planar structure and compact size of 30×50 mm2. Simulation and measured results show that realized gain in all operating bands is varied from -1.1 to 5 dBi. The proposed antenna demonstrates good impedance matching, stable radiation pattern and reasonable gain at all frequency bands. Simulation results have been obtained from commercial CST-2014 Microwave Studio. The antenna is fabricated and tested using R&S ZVL 13 Vector Network Analyzer (VNA). There are accepted results between the prototype and the simulated one.

Stress Intensity Factor in Hollow Square Sections Using Extended Finite Element Method

Qusai T. Abdulwaha

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 196-201
DOI: 10.30684/etj.36.2A.11

Hollow sections are extensively used in structural applications due to its good mechanical properties relative to weight. The presence of cracks in structural member may lead to catastrophic failure under different loading conditions. The presence of central crack in one side under tensile load is studied for different crack sizes (a/w) ranging from 0.1 to 0.8. The section is then investigated under bending moment for same crack size and geometry. The values of stress intensity factor (KI) were evaluated using Extended Finite Element Method (XFEM) and found very close between tensile and bending for same crack sizes but there was a difference in the shape factor values. The section is also investigated under tensile load but with the presence of edge crack with range of crack sizes (a/w) from 0.1 to 0.8. The results showed that the stress intensity factor in edge crack is much higher than central crack for same geometry and under same loading condition.

Entropy Generation Minimization Theoretical Analysis for External Flow Around Horizontal Cylinder at low Reynold Number

Louay A. Mahdi

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 202-206
DOI: 10.30684/etj.36.2A.12

The minimization of entropy generation is a helpful method to design optimum thermal system, and find an expression for entropy generation at several ranges of Reynolds number for heat transfer and friction flow irreversibility is a good way to achieve this goal. This study deal with several ranges of Reynolds number that cover 0.1< Re< 40000 divided into four groups. A relation between optimum Reynolds number, entropy generation number, irreversibility distribution ratio, and Began number was obtained. In addition, a relation between the optimum Reynolds number and the duty parameter was obtained for all Reynolds number ranges.

New Strategies for Associative Memories

Azad R. Kareem; Saja A. Talib

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 207-212
DOI: 10.30684/etj.36.2A.13

Associative memory is a neural network used to save collection of input and output data at its layers. Each output data is produced coincide with a given input. It can be useful as an artificial memory in many applications like (military, medical, data security systems, error detection and correction systems …etc.). There are two matters which limit the uses of associative memory; the limited storage capacity, and the error occurred in the reading of output data. A modified strategy is suggested to overcome these limitations by introducing a new algorithm to the design of the associative memory. This method provides a software solution to the problems. The obtained results from the test examples proved that the proposed associative memory net could train and recall unlimited patterns in different sizes efficiently and without any errors.

Sensor Network Based Animals Feeding and Milk Production Management System

Zena M. Faris; Muayad S. Croock

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 213-222
DOI: 10.30684/etj.36.2A.14

In general, the animals’ feeding requires a lot of time and efforts spent by the cattlemen. Part of the feeding amount is consumed by the animal to save its life and the other part is considered for instrumental milk production. The type of food in addition to the number of feeding frequents are important factors in changing the amount of produced milk as well as the weight of an animal. In this paper, we propose a control system that manage the forage process and the amount of produced milk by determining the quantity and number of feeding animals using sensor network. The designed system includes two parts: allocated hardware and data center. The hardware part consists of a microcontroller (ARDUINO Uno), Radio Frequency Identification (RFID) tags, level sensor, and Bluetooth HC-06. Sensors send their real-time readings of the forage quantity of animals to the monitoring part of the system through the Bluetooth service and then save them in the database server. RFID tags are used to recognize the cow types. There are two types of cows considered in this paper depending on the amount of produced milk. In the data center, the database is built using SQL server 2015 for storing the sensor readings and control signals of the proposed system. While the related Graphical User Interface (GUI) frames is designed using Visual Studio C#. The proposed system has been presented in a prototype to show forage process and resulted in a clear reduction in a daily cattlemen effort. The proposed system has been tested over different scenarios and the obtained results show the efficiency in terms of management part and food saving part

Influence of Spirals on the Behavior of Short RC Columns Strengthened by External CFRP

Kaiss F. Sarsam; Raid I. Khalel; Mohammed A. Hadi

Engineering and Technology Journal, 2018, Volume 36, Issue 2A, Pages 223-233
DOI: 10.30684/etj.36.2A.15

An experimental study was carried out to investigate the behavior of normal strength reinforced concrete (RC) circular short columns strengthened by carbon fiber reinforced polymer (CFRP) sheets. Three series comprising total of (15) specimens were loaded to failure under axial concentric compression load. Strengthening was varied by changing CFRP strips number, spacing and wrapping methods. The finding of this research can be summarized as follows; for the columns without CFRP, the influence of the spiral pitch was significant: compared with 100 mm spiral pitch, dropping the spacing to 65 mm and 30 mm increased the load carrying capacity by 25% and 43% respectively. The columns with less internal confinement (lesser amount of spirals) were strengthened more significantly by the CFRP than the ones with greater amount of internal spirals. As an example of the varying effectiveness of the fully wrapped CFRP, the column with spiral pitch at 100 mm was strengthened by 74% with the CFRP. In contrast, the ones with 30 mm spiral pitch only increased in strength with CFRP by 51%. Compared with the control specimen (no CFRP), the same amount of CFRP when used as spiral strips led to more strengthening than using CFRP as hoop strip-the former led to nearly 8% more strengthening than the latter in the case of 100 mm internal spiral pitch. In the case of 65 mm the internal spiral pitch, the difference (between the hoops &spiral CFRP strengthening)is close to 10.5%. The difference between the two methods of strengthening in the heavily spiral columns (30 mm spiral pitch) is more significant.