Now showing 1 - 10 of 27
  • Publication
    Comparison of hook and straight steel fibers addition on malaysian fly ash-based geopolymer concrete on the slump, density, water absorption and mechanical properties
    ( 2021) ; ;
    Ratnasamy Muniandy
    ;
    ;
    Katarzyna Błoch
    ;
    Bartłomiej Jeż
    ;
    Sebastian Garus
    ;
    Paweł Palutkiewicz
    ;
    ;
    Geopolymer concrete has the potential to replace ordinary Portland cement which can reduce carbon dioxide emission to the environment. The addition of different amounts of steel fibers, as well as different types of end-shape fibers, could alter the performance of geopolymer concrete. The source of aluminosilicate (fly ash) used in the production of geopolymer concrete may lead to a different result. This study focuses on the comparison between Malaysian fly ash geopolymer concrete with the addition of hooked steel fibers and geopolymer concrete with the addition of straight-end steel fibers to the physical and mechanical properties. Malaysian fly ash was first characterized by X-ray fluorescence (XRF) to identify the chemical composition. The sample of steel fiber reinforced geopolymer concrete was produced by mixing fly ash, alkali activators, aggregates, and specific amounts of hook or straight steel fibers. The steel fibers addition for both types of fibers are 0%, 0.5%, 1.0%, 1.5%, and 2.0% by volume percentage. The samples were cured at room temperature. The physical properties (slump, density, and water absorption) of reinforced geopolymer concrete were studied. Meanwhile, a mechanical performance which is compressive, as well as the flexural strength was studied. The results show that the pattern in physical properties of geopolymer concrete for both types of fibers addition is almost similar where the slump is decreased with density and water absorption is increased with the increasing amount of fibers addition. However, the addition of hook steel fiber to the geopolymer concrete produced a lower slump than the addition of straight steel fibers. Meanwhile, the addition of hook steel fiber to the geopolymer concrete shows a higher density and water absorption compared to the sample with the addition of straight steel fibers. However, the difference is not significant. Besides, samples with the addition of hook steel fibers give better performance for compressive and flexural strength compared to the samples with the addition of straight steel fibers where the highest is at 1.0% of fibers addition.
  • Publication
    Experiment on arm rehabilitation for muscle contraction monitoring using LabVIEW-based system
    (AIP Publishing, 2020)
    Z. Muhammad Fadil
    ;
    A. Izanoordina
    ;
    ;
    Patient that experiencing stroke or accident will leads to arm muscle paralysis and they could either suffer from partial arm paralysis or total arm paralysis. However, one of the challenge is to make the treatment session performs better. Currently, the patient has to go to rehabilitation centres or hospitals to get the treatment as the rehabilitation device is not portable. Furthermore, they have to go back and forth for recuperation session as accommodation or other facilities are not provided at certain rehabilitation centres. Therefore, the arm rehabilitation for muscle contraction monitoring system is developed to lessen the above issue. This project is focusing on patient's arm mobility to heal and maintain the strength of affected muscle. Thus, the doctor will be able to observe the patient's upper limb arm activity in real time monitoring using the Labview application. This system could assist the doctor to diagnose and analyse the current patient's arm performance from the recorded data. The parameters such as patient's hand grip, distal phalanges, elbow motion and bicep muscle contraction will determine the level of grip, the movement and the contraction activities via input from Arduino interface. Experiments have been conducted on 25 volunteers from different categories such as gender, age and physical condition based on proposed parameters. The results show that the development of arm rehabilitation for muscle contraction monitoring system could be used to determine the patient's condition based on the activity of finger gripped, muscle arm contraction and hand movement values as well as to strengthen the patient's arm throughout the rehabilitation process.
  • Publication
    Profiles of blades and paddles for turbines with geometric design inspired by nature
    (AIP Publishing, 2020)
    G. Poteraş
    ;
    György Deák
    ;
    M. V. Olteanu
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    I.-F. Burlacu
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    C. Sîrbu
    ;
    ;
    Exploitation of the main renewable energy sources (hydraulic, wind and solar radiation) in different installations involves the use of considerable surfaces, whether they are located on land or on water, having a negative impact on the environment. With the aim to dispose this deficiency, an installation that captures and integrates the three renewable resources has been proposed and patented. Therefore, their simultaneous exploitation in order to obtain electricity has the highest efficiency per unit area. In the laboratory, an installation was built and tested that integrates all three sources of renewable energy: The movement of water currents from flowing waters, the movement of air currents and solar radiation. Improvements that have been made to this pilot installation regarding the efficiency increasing of blades will be presented in the present communication, being analyzed the performance of using the profile blades with geometry inspired by nature.
  • Publication
    Development of geopolymer ceramic as a potential reinforcing material in solder alloy: short review
    (IOP Publishing, 2020)
    Nadiah ‘Izzati Zulkifli
    ;
    ; ;
    Andrei Victor Sandu
    ;
    ;
    Nowadays, the consumption of lead-free solder has been widely used around the world since the utilization of SnPb solder has been banned and restricted by European Union. Variety of studies have been conducted by the researchers to find an alternative to replace the usage of SnPb such as SnCu, SAC, SnAg and etc. However, the development of plain lead-free solder was declared to provide low mechanical, thermal, and electrical properties in terms of interfacial intermetallic compound and wettability towards its solder joint compare to the traditionally monolithic SnPb solder alloy. Mostly, previous studies stated that addition of some additives such as ceramic particles (Si 3 N 4, TiO 2, SiC, NiO and etc) may improves the solder joint reliability. At the same time, no major studies were done using geopolymer ceramic as reinforcing agent in plain matrix alloy. Therefore, this paper reviews the fabrication process of multiple geopolymer-based ceramic such as fly ash, kaolin, and slag as reinforcement in solder alloy. The development process includes the processing method of geopolymer ceramic and the characterization of geopolymer ceramic as reinforcing material consist of; i) chemical composition, and ii) phase identification.
  • Publication
    Mechanical and physical properties of bottom ash/fly ash geopolymer for pavement brick application
    ( 2020-03-18)
    Wan Ibrahim W.M.
    ;
    ;
    Ahmad R.
    ;
    ; ;
    Noor Azli M.A.A.
    Geopolymers are amorphous to semi-crystalline with excellent physical and and mechanical properties. It has been used to become a potential binder to Ordinary Portland Cement (OPC) in certain applications due to its lower emission of carbon dioxide gases and low energy consumption sustainability criteria. Bottom Ash (BA) is one of the main industrial by-products and it is produced at the bottom of the furnace during the coal combustion process in electricity generation. The application of BA as a sustainable construction material in the building industry plays an important role in order to decrease the volume of residual waste and conserving existing natural fine aggregates. The objectives for this study is to study the effect of fly ash to bottom ash ratio and to determine the optimum ratio of fly ash to bottom ash geopolymer for pavement brick application. The chemical composition and morphology of geopolymer reinforcement was analysed by using X-ray Fluorescence and Scanning Electron Microscope. The molarity of the Sodium Hydroxide solution is fixed at 12M. The parameter used in this study are different weight percentage of fly ash geopolymer 0 wt%, 10 wt%, 20 wt%, 30 wt% and 40 wt%. The solid to liquid ratios for this study is 2.0. The curing temperature of this study is 80°C and the curing time is 24 hours. 100% of bottom ash geopolymer is used as a control variable for this study.
      2  1
  • Publication
    Comparison of hook and straight steel fibers addition on malaysian fly ash‐based geopolymer concrete on the slump, density, water absorption and mechanical properties
    ( 2021-03-01)
    Faris M.A.
    ;
    ;
    Muniandy R.
    ;
    Hashim M.F.A.
    ;
    Błoch K.
    ;
    Jeż B.
    ;
    Garus S.
    ;
    Palutkiewicz P.
    ;
    ;
    Ghazali M.F.
    Geopolymer concrete has the potential to replace ordinary Portland cement which can reduce carbon dioxide emission to the environment. The addition of different amounts of steel fibers, as well as different types of end‐shape fibers, could alter the performance of geopolymer concrete. The source of aluminosilicate (fly ash) used in the production of geopolymer concrete may lead to a different result. This study focuses on the comparison between Malaysian fly ash geopolymer concrete with the addition of hooked steel fibers and geopolymer concrete with the addition of straight‐end steel fibers to the physical and mechanical properties. Malaysian fly ash was first characterized by x‐ray fluorescence (XRF) to identify the chemical composition. The sample of steel fiber reinforced geopolymer concrete was produced by mixing fly ash, alkali activators, aggregates, and specific amounts of hook or straight steel fibers. The steel fibers addition for both types of fibers are 0%, 0.5%, 1.0%, 1.5%, and 2.0% by volume percentage. The samples were cured at room temperature. The physical properties (slump, density, and water absorption) of reinforced geopolymer concrete were studied. Meanwhile, a mechanical performance which is compressive, as well as the flexural strength was studied. The results show that the pattern in physical properties of geopolymer concrete for both types of fibers addition is almost similar where the slump is decreased with density and water absorption is increased with the increasing amount of fibers addition. However, the addition of hook steel fiber to the geopolymer concrete produced a lower slump than the addition of straight steel fibers. Meanwhile, the addition of hook steel fiber to the geopolymer concrete shows a higher density and water absorption compared to the sample with the addition of straight steel fibers. However, the difference is not significant. Besides, samples with the addition of hook steel fibers give better performance for compressive and flexural strength compared to the samples with the addition of straight steel fibers where the highest is at 1.0% of fibers addition.
      1  16
  • Publication
    Finite element analysis on structural behaviour of geopolymer reinforced concrete beam using Johnson-Cook Damage in ABAQUS
    ( 2022) ; ;
    Rafiza Abdul Razak
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    ; ; ;
    Noorfifi Natasha Shahedan
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    Long Yuan Li
    ;
    Ikmal Hakem A. Aziz
    This paper details a finite element analysis of the behaviour of Si-Al geopolymer concrete beam reinforced steel bar under an impulsive load and hyper velocity speed up to 1 km/s created by an air blast explosion. The initial torsion stiffness and ultimate torsion strength of the beam increased with increasing compressive strength and decreasing stirrup ratio. The study involves building a finite element model to detail the stress distribution and compute the level of damage, displacement, and cracks development on the geopolymer concrete reinforcement beam. This was done in ABAQUS, where a computational model of the finite element was used to determine the elasticity, plasticity, concrete tension damages, concrete damage plasticity, and the viability of the Johnson-Cook Damage method on the Si-Al geopolymer concrete. The results from the numerical simulation show that an increase in the load magnitude at the midspan of the beam leads to a percentage increase in the ultimate damage of the reinforced geopolymer beams failing in shear plastic deformation. The correlation between the numerical and experimental blasting results confirmed that the damage pattern accurately predicts the response of the steel reinforcement Si-Al geopolymer concrete beams, concluded that decreasing the scaled distance from 0.298 kg/m3 to 0.149 kg/m3 increased the deformation percentage.
      2  17
  • Publication
    The development of arm rehabilitation for muscle contraction monitoring by using Labview
    (AIP Publishing, 2020)
    Izanoordina Ahmad
    ;
    Muhammad Fadil Zaidi
    ;
    Muscle paralysis can be defined as the loss of muscle function. This is caused by the failure of the nerves that send signals for muscle movement. It is often caused by the damage of nervous system especially at the spinal cord. Other major conditions of muscle paralysis are stroke, trauma and muscular dystrophy. This muscle function loss can be a partial or total muscle function loss. Partial muscle function loss or paralysis affects a part of the body whereas total muscle function loss affects the whole body. Arm paralysis is a partial paralysis of muscle function. It can be detected by feeling loss at the arm and unable to lift up the arm as there is sensory damage or motor damage of the arm. The only treatment to treat partial paralysis is through convalescence or rehabilitation. This includes physical therapy and occupational therapy for recuperation. Therefore, the development of arm rehabilitation for muscle contraction monitoring by using LabVIEW is in the scope of physical therapy where it is focuses on mobility, help to maintain and build any strength that remained in affected muscle. The distinctive part about this monitoring of muscle arm contraction rehabilitation development by using LabVIEW is the patients and doctors are able to see the progress in real time of the patient's arm muscle contraction. By using LabVIEW, it displays the data of recorded parameters on how much force is exerted from the patient's grip referring to index finger, middle finger and ring finger and rotation angle of the arm at the wrist and elbow when they move upward or downward. The sensors used are electromyogram sensor to detect muscle contraction, variable resistor for arm rotation angle and force sensitive resistor to detect the forces grip. From this, the activities of the patients? arm can be recognized
      1  11
  • Publication
    Optimization performance of unmanned aerial vehicle in wireless sensor network
    (AIP Publishing, 2020)
    Yumin Shakira Deraman
    ;
    Izanoordina Ahmad
    ;
    Aizat Faiz Ramli
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    An unmanned aerial vehicle (UAV) has been widely used in the Wireless Sensor Network for remote surveillance with number of advantages such as flexibility, mobility and ease of realization. The UAV can acts as a data collector or a relay between the central gateway and WSNs. The smart system in UAV are able to capture valuable data by using the right acquisition equipment and translate the information to better and faster data-driven decision. In despite of its success in many applications and field of studies, there are still open issues regarding the collaborative of UAV in Wireless Sensor Network such as an optimal trajectory design for the UAV, height between UAV and ground sensor nodes and energy management of the networks. This paper analyses the most common used algorithms to improve the performance of UAV-WSN. Each of the techniques are studied and a comprehensive analysis is presented.
      1  10
  • Publication
    Properties and behavior of geopolymer concrete subjected to explosive air blast loading: a review
    The severe damage to civilian buildings, public area, jet aircraft impact and defense target under explosive blast loading can cause a huge property loss. Most of researcher discusses the topics on design the concrete material model to sustain againts the explosive detonation. The implementation of modern reinforcement steels and fibres in ordinary Portland cement (OPC) concrete matrix can reduce the extreme loading effects. However, most researchers have proved that geopolymer concrete (GPC) has better mechanical properties towards high performance concrete, compared to OPC. GPC has the high early compressive strength and high ability to resist the thermal energy from explosive detonation. In addition, OPC production is less environmental friendly than geopolymer cement. Geopolymer used can lead to environmental protection besides being improved in mechanical properties. Thus, this paper highlighted on an experimental, numerical and the analytical studies cause of the explosive detonation impact to concrete structures.
      8  10