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Mohd. Mustafa Al Bakri Abdullah
Preferred name
Mohd. Mustafa Al Bakri Abdullah
Official Name
Abdulah, Mohd. Mustafa Al Bakri
Alternative Name
Abdullah, M.M.A.
M.M.A. Abdullah
Mustafa Al Bakri, A. M.
Albakri Abdullah, M. M.
Main Affiliation
CeGeoGTech UniMAP
Scopus Author ID
53164519100
Now showing
1 - 6 of 6
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PublicationRecent Developments in Steelmaking Industry and Potential Alkali Activated Based Steel Waste: A Comprehensive Review( 2022-03-01)
;Ikmal Hakem Aziz ; ; ; ;Li L.Y. ;Sandu A.V. ;Vizureanu P. ;Nemes O.Mahdi S.N.The steel industry is responsible for one-third of all global industrial CO2 emissions, putting pressure on the industry to shift forward towards more environmentally friendly production methods. The metallurgical industry is under enormous pressure to reduce CO2 emissions as a result of growing environmental concerns about global warming. The reduction in CO2 emissions is normally fulfilled by recycling steel waste into alkali-activated cement. Numerous types of steel waste have been produced via three main production routes, including blast furnace, electric arc furnace, and basic oxygen furnace. To date, all of the steel waste has been incorporated into alkali activation system to enhance the properties. This review focuses on the current developments over the last ten years in the steelmaking industry. This work also summarizes the utilization of steel waste for improving cement properties through an alkali activation system. Finally, this work presents some future research opportunities with regard to the potential of steel waste to be utilized as an alkali-activated material.3 23 -
PublicationGeopolymer as underwater concreting material: A review( 2021-07-12)
;Fakhryna Hannanee Ahmad Zaidi ; ; ; ; ;Li L.Y.Ediati R.Underwater concrete is one of the special types of high-performance concrete in the current industry which is commonly used to construct bridges, dams and structures whose foundation is built underwater. In contrast with typical concrete, the implementation of concrete underwater requires different techniques due to the different concrete properties in order to ensure successful implementation. A new material called geopolymer is now widely promoted for its ability to replace ordinary Portland cement (OPC) as a binder due to its green technology. Numerous researches have established that the geopolymer has comparable strength and chemical resistivity compared to OPC. However, to date, only limited researches had been conducted to examine the use of geopolymer as an underwater concreting material. From the review that has been done, it can be concluded that the requirements for underwater concreting material should include washout resistivity, workability and durability in addition to high strength. This review highlights that the geopolymers are proven to provide excellent strength, durability and workability in accordance with the EFNARC standard. Finally, future research opportunities are also presented in this review with regards to the potential of geopolymer in replacing OPC as underwater concreting material.1 32 -
PublicationFINITE ELEMENT ANALYSIS ON STRUCTURAL BEHAVIOUR OF GEOPOLYMER REINFORCED CONCRETE BEAM USING JOHNSON-COOK DAMAGE IN ABAQUS( 2022-01-01)
; ; ; ; ; ; ;Noorfifi Natasha Shahedan ;Li L.Y.Ikmal Hakem Abdul AzizThis 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 31 -
PublicationComparative mechanical and microstructural properties of high calcium fly ash one-part geopolymers activated with Na2SiO3-anhydrous and NaAlO2( 2021-11-01)
;Ooi Wan-En ; ; ; ;Li L.Y. ; ; ;Ong Shee-Ween ;Ng Hui-Teng ;Ng Yong-SingNur Ain JayaThis paper investigates the effect of varying solid alkali activators on the fresh and hardened properties and microstructural changes of one-part geopolymers (OPGs). Single and binary solid alkali activators were used to activate high calcium fly ash. The alkali activators were either solely sodium metasilicate (Na2SiO3) or a combination of sodium aluminate (NaAlO2) and sodium metasilicate (Na2SiO3). The OPG activated with anhydrous Na2SiO3 achieved an excellent 28-day compressive strength of 83.6 MPa while OPG activated with NaAlO2 and Na2SiO3 attained a compressive strength of 45.1 MPa. The Na2SiO3-activated OPG demonstrated better fluidity than the OPG activated with NaAlO2 and Na2SiO3 due to the thixotropic behaviour caused by the NaAlO2. The Na2SiO3-activated OPG consisted of sodium-calcium aluminium silicate hydrate ((N,C)-A-S-H) gel phase, while the OPG activated with NaAlO2 and Na2SiO3 comprised of the coexistence of sodium aluminium silicate hydrate (N-A-S-H) and calcium aluminium silicate hydrate (C-A-S-H) gel phases. Regardless of the distinctive properties, the OPGs are adequate for building materials applications.2 -
PublicationFinite element analysis on structural behaviour of geopolymer reinforced concrete beam using Johnson-Cook damage in Abaqus( 2022-01-01)
; ; ; ; ; ;Hilmi A.H. ;Shahedan N.N. ;Li L.Y.Aziz I.H.A.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.1 39 -
PublicationSeawater Exposure Effect on Fly Ash based Geopolymer Concrete with Inclusion of Steel Fiber( 2020-03-18)
; ; ;Jing L.Y. ;Li L.Y.Concrete is widely used in construction offshore such as concrete floating bridges and sea tank. This research is providing an alternative construction material to replace ordinary Portland cement (OPC) concrete known as geopolymer. The geopolymer concrete was produced by mixing fly ash with alkaline activator and 3% of steel fibre in order to improve the properties of fiber reinforced geopolymer concrete (FRGPC). The effects of aging period in term of strength, changes in weight and carbonation of FRGPC in seawater is investigated and compared with the fiber reinforced concrete (FROPC). The compressive strength obtained for FRGPC were higher than FROPC. The highest compressive strength obtained by FRGPC is 76.87 MPa at 28 days and 45.63 MPa at 28 days for FROPC concrete. The compressive strength was decreased as the period of immersing the concrete in seawater is increased. During the immersion process of both samples in seawater up to 120 days, the carbonation was not detected even though with the existence of steel fibres.3 21