Now showing 1 - 8 of 8
  • Publication
    Crumb rubber geopolymer mortar at elevated temperature exposure
    ( 2022) ; ;
    Che Mohd Ruzaidi Ghazali
    ;
    ;
    Ramadhansyah Putra Jaya
    ;
    ;
    Mohammad A. Almadani
    ;
    Wysłocki, Jerzy J.
    ;
    Agata Śliwa
    ;
    Andre Victor Sandu
    Low calcium fly ash is used as the main material in the mixture and the crumb rubber was used in replacing fine aggregates in geopolymer mortar. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) which were high alkaline solution were incorporated as the alkaline solution. The fly ash reacted with the alkaline solution forming alumino-silicate gel that binds the aggregate to produce a geopolymer mortar. The loading of crumb rubber in the fly ash based geopolymer mortar was set at 0%
  • Publication
    Contribution of interfacial bonding towards geopolymers properties in geopolymers reinforced fibers: a review
    ( 2022)
    Muhd Hafizuddin Yazid
    ;
    ; ;
    Marcin Nabiałek
    ;
    ; ;
    Marwan Kheimi
    ;
    Andrei Victor Sandu
    ;
    Adam Rylski
    ;
    Bartłomiej Jeż
    There is a burgeoning interest in the development of geopolymers as sustainable construction materials and incombustible inorganic polymers. However, geopolymers show quasi-brittle behavior. To overcome this weakness, hundreds of researchers have focused on the development, characterization, and implementation of geopolymer-reinforced fibers for a wide range of applications for light geopolymers concrete. This paper discusses the rapidly developing geopolymer-reinforced fibers, focusing on material and geometrical properties, numerical simulation, and the effect of fibers on the geopolymers. In the section on the effect of fibers on the geopolymers, a comparison between single and hybrid fibers will show the compressive strength and toughness of each type of fiber. It is proposed that interfacial bonding between matrix and fibers is important to obtain better results, and interfacial bonding between matrix and fiber depends on the type of material surface contact area, such as being hydrophobic or hydrophilic, as well as the softness or roughness of the surface.
  • Publication
    Metakaolin/sludge based geopolymer adsorbent on high removal efficiency of Cu2+
    ( 2022)
    Pilomeena Arokiasamy
    ;
    ; ;
    Mohd Remy Rozainy Mohd Arif Zainol
    ;
    ;
    Marwan Kheimi
    ;
    Andrei Victor Sandu
    ;
    Petrica Vizureanu
    ;
    Rafiza Abdul Razak
    ;
    Activated carbon (AC) has received a lot of interest from researchers for the removal of heavy metals from wastewater due to its abundant porous structure. However, it was found unable to meet the required adsorption capacity due to its amorphous structure which restricts the fundamental studies and structural optimization for improved removal performance. In addition, AC is not applicable in large scale wastewater treatment due its expensive synthesis and difficulty in regeneration. Thus, the researchers are paying more attention in synthesis of low cost geopolymer based adsorbent for heavy metal removal due its excellent immobilization effect. However, limited studies have focused on the synthesis of geopolymer based adsorbent for heavy metal adsorption by utilizing industrial sludge. Thus, the aim of this research was to develop metakaolin (MK) based geopolymer adsorbent with incorporation of two types of industrial sludge (S1 and S3) that could be employed as an adsorbent for removing copper (Cu²⁺) from aqueous solution through the adsorption process. The effects of varied solid to liquid ratio (S/L) on the synthesis of metakaolin/sludge based geopolymer adsorbent and the removal efficiency of Cu²⁺ by the synthesis adsorbent were studied. The raw materials and synthesized geopolymer were characterized by using x-ray fluorescence (XRF), x-ray diffraction (XRD), scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) and micro XRF. The concentration of Cu²⁺ before and after adsorption was determined by atomic absorption spectroscopy (AAS) and the removal efficiency was calculated. The experimental data indicated that the synthesized geopolymer at low S/L ratio has achieved the highest removal efficiency of Cu²⁺ about 99.62% and 99.37% at 25%:75% of MK/S1 and 25%:75% of MK/S3 respectively compared to pure MK based geopolymer with 98.56%. The best S/L ratio for MK/S1 and MK/S3 is 0.6 at which the reaction between the alkaline activator and the aluminosilicate materials has improved and enhanced the geopolymerization process. Finally, this work clearly indicated that industrial sludge can be utilized in developing low-cost adsorbent with high removal efficiency
  • Publication
    Artificial lightweight aggregates made from pozzolanic material: A review on the method, physical and mechanical properties, thermal and microstructure
    ( 2022)
    Dickson Ling Chuan Hao
    ;
    ;
    Marwan Kheimi
    ;
    ; ;
    Dumitru Doru Burduhos Nergis
    ;
    Hamzah Fansuri
    ;
    Ratna Ediati
    ;
    Rosnita Mohamed
    ;
    As the demand for nonrenewable natural resources, such as aggregate, is increasing worldwide, new production of artificial aggregate should be developed. Artificial lightweight aggregate can bring advantages to the construction field due to its lower density, thus reducing the dead load applied to the structural elements. In addition, application of artificial lightweight aggregate in lightweight concrete will produce lower thermal conductivity. However, the production of artificial lightweight aggregate is still limited. Production of artificial lightweight aggregate incorporating waste materials or pozzolanic materials is advantageous and beneficial in terms of being environmentally friendly, as well as lowering carbon dioxide emissions. Moreover, additives, such as geopolymer, have been introduced as one of the alternative construction materials that have been proven to have excellent properties. Thus, this paper will review the production of artificial lightweight aggregate through various methods, including sintering, cold bonding, and autoclaving. The significant properties of artificial lightweight aggregate, including physical and mechanical properties, such as water absorption, crushing strength, and impact value, are reviewed. The properties of concrete, including thermal properties, that utilized artificial lightweight aggregate were also briefly reviewed to highlight the advantages of artificial lightweight aggregate.
  • Publication
    Geopolymer-based artificial aggregates: a review on methods of producing, properties, and improving techniques
    ( 2022)
    Mohammad Almadani
    ;
    ; ;
    Rosnita Mohamed
    The depletion of aggregate-related natural resources is the primary concern of all researchers globally. Recent studies emphasize the significance of recycling and reusing various types of natural or by-product material waste from industry as a result of the building industry’s rising demand for aggregate as the primary component in concrete production. It has been demonstrated that the geopolymer system has exceptional features, such as high strength, superior durability, and greater resistance to fire exposure, making it a viable alternative to ordinary Portland Cement (OPC) concrete. This study will examine the present method utilized to generate artificial aggregate-based geopolymers, including their physical and mechanical properties, as well as their characterization. The production process of geopolymer derived from synthetic aggregates will be highlighted. In conjunction with the bonding of aggregates and the cement matrix, the interfacial transition zone (ITZ) is highlighted in this work as an additional important property to be researched in the future. It will be discussed how to improve the properties of geopolymers based on artificial aggregates. It has been demonstrated that cold bonding provides superior qualities for artificial aggregate while conserving energy during production. The creation of ITZ has a significant impact on the bonding strength between artificial aggregates and the cement matrix. Additionally, improvement strategies demonstrate viable methods for enhancing the quality of manufactured aggregates. In addition, other recommendations are discussed in this study for future work.
  • Publication
    Contribution of interfacial bonding towards geopolymers properties in geopolymers reinforced fibers: A review
    ( 2022)
    Muhd Hafizuddin Yazid
    ;
    ; ;
    Marcin Nabiałek
    ;
    ; ;
    Marwan Kheimi
    ;
    Andrei Victor Sandu
    ;
    Adam Rylski
    ;
    Bartłomiej Jeż
    There is a burgeoning interest in the development of geopolymers as sustainable construction materials and incombustible inorganic polymers. However, geopolymers show quasi-brittle behavior. To overcome this weakness, hundreds of researchers have focused on the development, characterization, and implementation of geopolymer-reinforced fibers for a wide range of applications for light geopolymers concrete. This paper discusses the rapidly developing geopolymer-reinforced fibers, focusing on material and geometrical properties, numerical simulation, and the effect of fibers on the geopolymers. In the section on the effect of fibers on the geopolymers, a comparison between single and hybrid fibers will show the compressive strength and toughness of each type of fiber. It is proposed that interfacial bonding between matrix and fibers is important to obtain better results, and interfacial bonding between matrix and fiber depends on the type of material surface contact area, such as being hydrophobic or hydrophilic, as well as the softness or roughness of the surface.
      5  21
  • Publication
    Mechanical performance of Fly Ash based Geopolymer (FAG) as road base stabilizer
    ( 2022) ; ;
    Andrei Victor Sandu
    ;
    Thanongsak Imjai
    ;
    Petrica Vizureanu
    ;
    Mohd Rosli Mohd Hasan
    ;
    Mohammad Almadani
    ;
    Ikmal Hakem Ab Aziz
    ;
    This study examines the strength development of fly ash-based geopolymer (FAG) as a stabilizer for road base material for pavement construction. In the last decade, there has been a rapid development of conventionally treated bases, such as cement-treated bases. However, a major problem with this kind of application is the shrinkage cracking in cement-treated bases that may result in the reflection cracks on the asphalt pavement surface. This study explores the effects of FAG on base layer properties using mechanistic laboratory evaluation and its practicability in pavement base layers. The investigated properties are flexural strength (FS), unconfined compressive strength (UCS), shrinkage, and resilient modulus (RM), as well as indirect tensile strength (ITS). The findings showed that the mechanical properties of the mixture enhanced when FAG was added to 80–85% of crushed aggregate, with the UCS being shown to be a crucial quality parameter. The effectiveness of FAG base material can have an impact on the flexible pavements’ overall performance since the base course stiffness directly depends on the base material properties. As a stabilizing agent for flexible pavement applications, the FAG-stabilized base appeared promising, predicated on test outcomes.
      2  4
  • Publication
    Metakaolin/sludge based geopolymer adsorbent on high removal efficiency of Cu2+
    ( 2022)
    Pilomeena Arokiasamy
    ;
    ; ;
    Mohd Remy Rozainy Mohd Arif Zainol
    ;
    ;
    Marwan Kheimi
    ;
    Jitrin Chaiprapa
    ;
    Andrei Victor Sandu
    ;
    Petrica Vizureanu
    ;
    ;
    Activated carbon (AC) has received a lot of interest from researchers for the removal of heavy metals from wastewater due to its abundant porous structure. However, it was found unable to meet the required adsorption capacity due to its amorphous structure which restricts the fundamental studies and structural optimization for improved removal performance. In addition, AC is not applicable in large scale wastewater treatment due its expensive synthesis and difficulty in regeneration. Thus, the researchers are paying more attention in synthesis of low cost geopolymer based adsorbent for heavy metal removal due its excellent immobilization effect. However, limited studies have focused on the synthesis of geopolymer based adsorbent for heavy metal adsorption by utilizing industrial sludge. Thus, the aim of this research was to develop metakaolin (MK) based geopolymer adsorbent with incorporation of two types of industrial sludge (S1 and S3) that could be employed as an adsorbent for removing copper (Cu2+) from aqueous solution through the adsorption process. The effects of varied solid to liquid ratio (S/L) on the synthesis of metakaolin/sludge based geopolymer adsorbent and the removal efficiency of Cu2+ by the synthesis adsorbent were studied. The raw materials and synthesized geopolymer were characterized by using x-ray fluorescence (XRF), x-ray diffraction (XRD), scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) and micro XRF. The concentration of Cu2+ before and after adsorption was determined by atomic absorption spectroscopy (AAS) and the removal efficiency was calculated. The experimental data indicated that the synthesized geopolymer at low S/L ratio has achieved the highest removal efficiency of Cu2+ about 99.62 % and 99.37 % at 25 %:75 % of MK/S1 and 25 %:75 % of MK/S3 respectively compared to pure MK based geopolymer with 98.56 %. The best S/
      2  8