Research Title: Experimental and numerical study of strengthening and repairing heat-damaged RC circular column using hybrid system of CFRP

Author: Ala Taleb Obaidat, Published Year: 2022

Case Studies in Construction Materials,

Faculty: Engineering and Technology

Abstract: This study aims to investigate the behavior of heat damaged reinforced concrete RC circular column considering effect of heat and repair technique. Six RC circular column with diameter of 185 mm and 800 mm in height were cast, heated at 400 °C and 600 °C for 3 h, strengthened and repaired with hybrid system of CFRP and then tested under concentric load. Also, four RC circular columns from Obaidat et al. (2020) [3] were used for comparison. Complementary to the experimental investigation, a finite element modeling (FEM) was developed to simulate the compression behavior of heat damaged RC circular column. The result showed that specimens strengthened and repaired with hybrid system SC-H23-COMP and (DC-H400-COM and DC-H600-COM) exhibited the higher improvement in compression capacity about 100.4% and (86.7% and 53%), receptively, more than the control specimens. It was concluded that as the temperature increases the strength of the specimen decreases. Moreover, the strength in repaired specimens by hybrid system increased by 64.9% and 48.85% more than unheated control RC column specimen CC-COM. Finally, the FEM results provides a good agreement with experimental results and the model capable to predict the compression behavior of the RC circular column.

Keywords: Heat damagedStrengtheningRepairingCarbon fiber reinforced polymers CFRPHybrid systemStress-strainRC circular columnFinite element model

Research Title: BehaviBehaviour of heat damaged repaired reinforced SCC cantilever beam using carbon fiber reinforced polymer rope

Author: Ala Taleb Obaidat, Published Year: 2022

Faculty: Engineering and Technology

Abstract: This study investigated the behaviour of self-compacted cantilever concrete (SCCC) beams exposed to high temperature and repaired using near surface mounted carbon fibre (NSM-CFRP) rope. Nine (SCCC) beam specimens with cross sectional area of (150 mm × 150 mm) and 750 mm in length were constructed and tested. Seven beam specimens were exposed to 400 °C and 500 °C for two hours and then repaired using NSM-CFRP rope. The tested SCCC specimens were divided into four groups to study the effect of temperature, location and number of NSM rope. Results showed that using NSM-CFRP rope as retrofitting or strengthening techniques at the sides of cantilever beam had a significant effect on load-deflection behaviour compared to other techniques. It was concluded that using NSM-CFRP rope as retrofitting or strengthening techniques depend on the number of rope and position of ropes. Moreover, increasing the number of ropes to two at top of the beam had a limited impact upon load capacity. On the other hand, rehabilitated (SCC) beams specimens damaged by heat up to 500 °C for 2 h with two CFRP ropes at sides and top surface exhibited load capacity about 197% and 101%, respectively, as control specimen.

Keywords: Heat damagedstrengtheningrepairingcarbon fibre reinforced polymers (CFRP)stress-strainself-compacted cantilever concrete (SCC)

Research Title: Experimental and analytical investigation of using externally bonded, hybrid, fiber-reinforced polymers to repair and strengthen heated, damaged RC beams in flexure

Author: Ala Taleb Obaidat, Published Year: 2022

Faculty: Engineering and Technology

Abstract: Purpose – This study aims to conduct an experimental study and finite element model (FEM) to investigate the flexural behavior of heat-damaged beams strengthened/repaired by hybrid fiber-reinforced polymers (HFRP). Design/methodology/approach – Two groups of beams of (150 3 250 3 1,200) mm were cast, strengthened and repaired using different configurations of HFRP and tested under four-point loadings. The first group was kept at room temperature, while the second group was exposed to a temperature of 4008C. Findings – It was found that using multiple layers of carbon fiber-reinforced polymer (CFRP) and glass fiberreinforced polymer (GFRP) enhanced the strength more than a single layer. Also, the order of two layers of FRP showed no effect on flexural behavior of beams. Using a three-layer scheme (attaching the GFRP first and followed by two layers of CFRP) exhibited increase in ultimate load more than the scheme attached by CFRP first. Furthermore, the scheme HGC (heated beam repaired with glass and carbon, in sequence) allowed to achieve residual flexural capacity of specimen exposed to 4008C. Typical flexural failure was observed in control and heat-damaged beams, whereas the strengthened/repaired beams failed by cover separation and FRP debonding, however, specimen repaired with two layers of GFRP failed by FRP rupture. The FEM results showed good agreement with experimental results. Originality/value – Few researchers have studied the effects of HFRP on strengthening and repair of heated, damaged reinforced concrete (RC) beams. This paper investigates, both experimentally and analytically, the performance of externally strengthened and repaired RC beams, in flexure, with different FRP configurations of CFRP and GFRP.

Keywords: Hybrid fiber-reinforced polymers, Heat, Repairing, Strengthening, RC beams, Flexure, Glass FRP, Carbon FRP

Research Title: Modeling of confined circular RC columns using artificial neural network and finite element method

Author: Ala Taleb Obaidat, Published Year: 2022

Structures, 40

Faculty: Engineering and Technology

Abstract: A Finite Element (FE) and an Artificial Neural Network (ANN) model were developed to investigate the effect of different parameters, such as the space between stirrups and the diameter of longitudinal steel, on the behavior of circular Reinforced-Concrete (RC) columns confined with fiber reinforced polymer (FRP) sheets using the actual hoop rupture strain of the FRP. The FE model was accomplished using the FE software ABAQUS 6.13 which incorporates the nonlinear behavior of concrete material, the bilinear stress–strain curve of steel, and the linear elastic behavior of FRP. It was found that there is a good agreement between the FE model (FEM) results and the experiments. The ANNs were trained and tested on an experimental database from the literature. The database contains the experimental ultimate FRP strain, and the ultimate load results of 92 FRP confined circular RC columns. The ANN results agreed well with the FEM results. The neural network results were carried out to develop empirical equations to predict the effective rupture FRP strain and the ultimate load for circular confined RC columns with R2 of 0.912 and 0.932, respectively. The proposed equations estimate the ultimate strain from experimental works of the FRP with a small error up to 20%. In addition, the predicted results from the proposed equations exhibited good accuracy compared with previous guidelines and experimental and FE results from the literature, and it can be easily used in engineering designs as well.

Keywords: Fiber reinforced polymer (FRP)ConcreteColumnConfinementFinite element analysis (FEA)Artificial neural network (ANN)

Research Title: V2V BER Enhancement based on FFH-OFDM

Author: Qadri Jamal Al-Hamarsheh, Published Year: 2021

The 2nd International Conference on Distributed Sensing and Intelligent Systems (ICDSIS2021, China

Faculty: Engineering and Technology

Abstract: This paper describes the performance enhancement for the V2V communications based on LTE systems. Due to the mobility factor among the communicating nodes, V2V systems have a major drawback from the bandwidth point of view. Thus, a study of the V2V systems based on BER performance enhancement has been investigated. This proposition is based on making use of both of fast frequency hopping orthogonal frequency division multiplexing and the multiple antennas to mitigate the Doppler spread effect on the V2V clustering benchmark, which contains both of a clustering weighting factor based stage and a multiparallel processing stage. The results show a noticeable stability compared to our previously published work by almost 25%, which also exceeds the achieved results from the Lower-ID DCA from both of the speed and communication range.

Keywords: OFDM, FFH, V2V, Clustering Algorithm

Research Title: Compression behavior of confined circular reinforced concrete with spiral CFRP rope with different slenderness ratios

Author: Ala Taleb Obaidat, Published Year: 2022

Results in Engineering, 16

Faculty: Engineering and Technology

Abstract: https://doi.org/10.1016/j.rineng.2022.10

Keywords: Carbon Fibre Reinforced Polymers (CFRP); strengthening; reinforced concrete beam; flexure; debonding

Research Title: Enhancing the LTE-Based Intelligent Transportation System’s Performance

Author: Qadri Jamal Al-Hamarsheh, Published Year: 2021

Wireless Personal Communications, vol. 117, no. 3

Faculty: Engineering and Technology

Abstract: Intelligent transportation system is considered as one of the main features of the new generation of the wireless systems. Furthermore, both of high speed data transmission and processing play a crucial role for these generations. In this work, two main propositions have been detailed in order to attain an improvement in such intelligent systems performance and to enhance both of data transmission and processing speed. Thus, a proposed clustering algorithm will be presented for grouping mobile nodes based on their speeds besides the assignments of the head nodes that will not be updated every cycle, while the ordinary ones themselves will execute their attaching heads continuously. In order to enhance the speed of data transmission and processing, a parallel-processing technique is emphasized. This is based on a variety of wavelet baby functions to attain the target of increasing the speed with low complexity. In addition, the optimization of the transmitted power phenomenon, the Multiband orthogonal frequency division multiplexing is used to provide such privilege via the parallel processing criterion. There have been five main efficiency factors involved in this investigation; namely complementary cumulative distributions, bit rates, energy efficiency, the cluster head life time and the ordinary nodes reattaching-head average times.

Keywords: UWB-MB-OFDM · V2V · Energy efficiency · Clustering algorithm

Research Title: Robust Vehicular Communications Using the Fast-Frequency-Hopping-OFDM Technology and the MIMO Spatial Multiplexing

Author: Qadri Jamal Al-Hamarsheh, Published Year: 2022

International Journal of Communication Networks and Information Security (IJCNIS), vol. 14, no. 1

Faculty: Engineering and Technology

Abstract: Vehicle-to-Vehicle communication is one of the more emerging technologies in the 21st century from either the comfortable transportation or safer transportation point of view. Vehicle-to-Vehicle communication has one crucial factor, which is the huge information to be shared among vehicles, such as the position, the road data. In such situation, the accurate information sharing process is the most important factor in order to make the vehicles operating in the most feasible way. This work proposes a more robust vehicle communication system to make the existing vehicle transportation system more efficient. In this paper, we propose a fast frequency hopping orthogonal frequency division multiplexing to mitigate the Doppler spread effect on our previously published clustering benchmark. This benchmark contains both of a clustering weighting factor based stage and a multiparallel processing stage. This is in addition to modify the PHY layer of the existing IEEE 802.11p standard in order to impose Multiple Input Multiple Output for higher throughput purposes. The results show a noticeable stability compared to our previously published work. Furthermore, the results are almost exceeds the achieved results from the Lower-ID Distributed Clustering Algorithm (DCA) from both of the speed and communication range

Keywords: OFDM, Fast Frequency Hopping, V2V, Doppler Spread, Clustering Algorithm, MIMO.

Research Title: Autoregressive Modeling based ECG Cardiac Arrhythmias’ Database System

Author: Qadri Jamal Al-Hamarsheh, Published Year: 2022

INTERNATIONAL JOURNAL OF CIRCUITS, SYSTEMS AND SIGNAL PROCESSING, Volume 16

Faculty: Engineering and Technology

Abstract: This article proposes an ECG (electrocardiography) database system based on linear filtering, wavelet transform, PSD analysis, and adaptive AR modeling technologies to distinguish 19 ECG beat types for classification. This paper uses the Savitzky-Golay filter and wavelet transform for noise reduction, and wavelet analysis and AR modeling techniques for feature extraction to design a database system of AR coefficients describing the ECG signals with different arrhythmia types. In the experimental part of this work, the proposed algorithm performance is evaluated using an ECG dataset containing 19 different types including normal sinus rhythm, atrial premature contraction, ventricular premature contraction, ventricular tachycardia, ventricular fibrillation, supraventricular tachycardia, and other types from the MIT-BIH Arrhythmia Database. The simulation is performed in a MATLAB environment.

Keywords: AR modeling, arrhythmia classification, Discrete Wavelet Transform, ECG noise analysis, power spectral density (PSD).

Research Title: Productive and Sustainable H2 Production from Waste Aluminum Using Copper Oxides-Based Graphene Nanocatalysts: A Techno-Economic Analysis

Author: Firas Abdullah Obeidat, Published Year: 2022

Sustainability (MDPI), 14(22)

Faculty: Engineering and Technology

Abstract: Hydrogen has universally been considered a reliable source of future clean energy. Its energy conversion, processing, transportation, and storage are techno-economically promising for sustainable energy. This study attempts to maximize the production of H2 energy using nanocatalysts from waste aluminum chips, an abundant metal that is considered a potential storage tank of H2 energy with high energy density. The present study indicates that the use of waste aluminum chips in the production of H2 gas will be free of cost since the reaction by-product, Al2O3, is denser and can be sold at a higher price than the raw materials, which makes the production cost more efficient and feasible. The current framework investigates seven different copper oxide-based graphene nanocomposites that are synthesized by utilizing green methods and that are well-characterized in terms of their structural, morphological, and surface properties. Reduced graphene oxide (rGO) and multi-layer graphene (MLG) are used as graphene substrates for CuO and Cu2O NPs, respectively. These graphene materials exhibited extraordinary catalytic activity, while their copper oxide composites exhibited a complete reaction with feasible techno-economic production. The results revealed that the H2 production yield and rates increased twofold with the use of these nanocatalysts. The present study recommends the optimum reactor design considerations and reaction parameters that minimize water vaporization in the reaction and suggests practical solutions to quantify and separate it. Furthermore, the present study affords an economic feasibility approach to producing H2 gas that is competitive and efficient. The cost of producing 1 kg of H2 gas from waste aluminum chips is USD 6.70, which is both economically feasible and technically applicable. The unit cost of H2 gas can be steeply reduced by building large-scale plants offering mass production. Finally, the predicted approach is applicable in large, medium, and small cities that can collect industrial waste aluminum in bulk to generate large-scale energy units.

Keywords: graphene; copper oxide; waste aluminum; hydrogen production; nanocomposites; catalysts