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Study of Zeolite Phase Made from Rice Husk Ash and Sidrap Clay

Armayani M., Mansur Musdalifa, Asra Reza, Irwan Muh, Ramadhanty Dhian, Subaer Subaer, Abdullah Mohd Mustafa Al Bakri, Aziz Ikmal Hakem A., Jeż Bartłomiej, Nabiałek Marcin

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 1

269--274

EN

Zeolite has been successfully synthesized from clay and rice husk ash in the form of powder by using the hydrothermal method with variations in chemical compositions of alkaline solution and the amount of rice husk ash. The clay raw material was obtained from the Sidrap area of South Sulawesi and rice husk ash is obtained from the burning pile of rice husks. Sidrap clay and rice husk ash were activated using an alkaline solution of NaOH and varied rice husk ash and the addition of AlCl3. The addition of AlCl3, an alkaline solution of NaOH and H2O was used in the amount of 25.5 grams and variations of rice husk ash were 2.5 grams and 6.5 grams. Meanwhile, without the addition of AlCl3, an alkaline solution of NaOH and H2O was used for 20.5 grams and variations of rice husk ash from 2.5 grams and 6.5 grams. Then the mixture was then put into an autoclave with a temperature of 100°C for 3 hours. The basic material used in the manufacture of zeolite is carried out by X-ray Fluorescence (XRF) characterization to determine the constituent elements of basic material, which showed the content of SiO2 was 45.80 wt% in the clay and 93.40% in the rice husk ash. The crystalline structure of the zeolite formed was characterized by X-Ray Diffraction (XRD). It was found the resulting zeolite were identified as Zeolite-Y, Hydrosodalite, and ZSM-5. The microstructure properties of the resulting zeolite were determined by using Scanning Electron Microscopy (SEM).

2

Thermal Insulation and Mechanical Properties in the Presence of Glas Bubble in Fly Ash Geopolymer Paste

Shahedan Noor Fifinatasha, Al Bakri Abdullah Mohd Mustafa, Mahmed Norsuria, Ming Liew Yun, Abd Rahim Shayfull Zamree, Aziz Ikmal Hakem A., Kadir Aeslina Abdul, Sandu Andrei Victor, Ghazali Mohd Fathullah

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 1

221--226

EN

The density, compressive strength, and thermal insulation properties of fly ash geopolymer paste are reported. Novel insulation material of glass bubble was used as a replacement of fly ash binder to significantly enhance the mechanical and thermal properties compared to the geopolymer paste. The results showed that the density and compressive strength of 50% glass bubble was 1.45 g/cm3 and 42.5 MPa, respectively, meeting the standard requirement for structural concrete. Meanwhile, the compatibility of 50% glass bubbles tested showed that the thermal conductivity (0.898 W/mK), specific heat (2.141 MJ/m3 K), and thermal diffusivity (0.572 mm2 /s) in meeting the same requirement. The improvement of thermal insulation properties revealed the potential use of glass bubbles as an insulation material in construction material.

3

Silica Bonding Reaction on Fly Ash Based Geopolymer Repair Material System with Incorporation of Various Concrete Substrates

Al Bakri Abdullah Mohd Mustafa, Aziz Ikmal Hakem A., Zailani Warid Wazien Ahmad, Rahim Shayfull Zamree Abd, Yong Heah Cheng, Sandu Andrei Victor, Peng Loke Siu

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 4

1277--1281

EN

This paper presents an experimental investigation on the mechanical properties and microstructure of geopolymer repair materials mixed using fly ash (FA) and concrete substrates. An optimal combination of FA and concrete substrate was determined using the compressive test of geopolymer mortar mixed with various concrete substrate classes. It was found that the contribution of (C35/45) concrete substrates with the FA geopolymer mortar increases the 28-day bonding strength by 25.74 MPa. The microstructure analysis of the samples using scanning electron microscopy showed the denser structure owing to the availability of high calcium and iron elements distribution. These metal cations (Ca2+ and Fe3+) are available at OPC concrete substrate as a result from the hydration process reacted with alumina-silica sources of FA and formed calcium aluminate silicate hydrate (C-A-S-H) gels and Fe-bonding linkages.

4

Finite Element Analysis on Structural Behaviour of Geopolymer Reinforced Concrete Beam using Johnson-Cook Damage in ABAQUS

Mortar Nurul Aida Mohd, Al Bakri Abdullah Mohd Mustafa, Hussin Kamarudin, Razak Rafiza Abdul, Hamat Sanusi, Hilmi Ahmad Humaizi, Shahedan Noorfifi Natasha, Li Long Yuan, Aziz Ikmal Hakem A.

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 4

1349--1354

EN

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.

5

Effect of NaOH Molar Concentration on Microstructure and Compressive Strength of Dolomite/Fly Ash-Based Geopolymers

Azimi Emy Aizat, Mohd Salleh M. A. A., Al Bakri Abdullah Mohd Mustafa, Aziz Ikmal Hakem A., Hussin Kamarudin, Chaiprapa Jitrin, Vizureanu Petrica, Yoriya Sorachon, Nabiałek Marcin, Wyslocki Jerzy J.

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 3

993--998

EN

Dolomite can be used as a source of aluminosilicate to produce geopolymers; however, this approach is limited by its low reactivity. This study analyzes the viability of producing geopolymers using dolomite/fly-ash with sodium silicate and NaOH solutions (at multiple concentrations) by determining the resultant geopolymers’ compressive strengths. The dolomite/fly-ash-based geopolymers at a NaOH concentration of ~22 M resulted in an optimum compressive strength of 46.38 MPa after being cured for 28 days, and the SEM and FTIR analyses confirmed the denser surface of the geopolymer matrix. The synchrotron micro-XRF analyses confirmed that the Ca concentration exceeded that of Si and Mg, leading to the formation of calcium silicate hydrate, which strengthens the resulting geopolymers.

6

Experimental investigation of chopped steel wool fiber at various ratio reinforced cementitious composite panels

Rmdan Amer Akrm A., Al Bakri Abdullah Mohd Mustafa, Ming Liew Yun, Aziz Ikmal Hakem A., Mohd Tahir Muhammad Faheem, Abd Rahim Shayfull Zamree, Amer Hetham A. R.

Archives of Civil Engineering

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2021

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Vol. 67, nr 3

661--671

EN

The flexural toughness of chopped steel wool fiber reinforced cementitious composite panels was investigated. Reinforced cementitious composite panels were produced by mixing of chopped steel wool fiber with a ratio range between 0.5% to 6.0% and 0.5% as a step increment of the total mixture weight, where the cement to sand ratio was 1:1.5 with water to cement ratio of 0.45. The generated reinforced cementitious panels were tested at 28 days in terms of load-carrying capacity, deflection capacities, post-yielding effects, and flexural toughness. The inclusion of chopped steel wool fiber until 4.5% resulted in gradually increasing load-carrying capacity and deflection capacities while, provides various ductility, which would simultaneously the varying of deflection capability in the post-yielding stage. Meanwhile, additional fiber beyond 4.5% resulted in decreased maximum load-carrying capacity and increase stiffness at the expense of ductility. Lastly, the inclusion of curves gradually.