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The Properties of Ground Granulated Blast Furnace Slag Lightweight Aggregate (GLA) at Various Molar Ratio and Its Application in Concrete

Razak Rafiza Abd, Hassan Mohd Akhmal, Abdullah Mohd Mustafa Al Bakri, Yahya Zarina, Ariffin Mohd Azreen Mohd, Mansor Ahmad Faizal B., Hao Dickson Ling Chuan

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 3

991-996

EN

The effects of supplementary cementitious materials (SCM) on the characteristics and internal structure of synthetic aggregate made from ground granulated blast furnace slag are investigated in this study (GGBS). Due to its high pozzolanic activity, GGBS was shown to be superior to other SCM materials, enhancing both the strength and durability of synthetic aggregate. Because sintering uses a lot of energy and generates a lot of pollutants, using a cold-bonded approach to make low density lightweight aggregates is particularly significant from an economic and environmental standpoint. Thus, the utilisation of ground granulated blast furnace slag (GGBS) as a substitute material in the production of green artificial lightweight aggregate (GLA) using the cold bonding method was discussed in this work. Admixtures of ADVA Cast 203 and Hydrogen Peroxide were utilised to improve the quality of GLA at various molar ratios. The freshly extracted GLA was then evaluated for specific gravity, water absorption, aggregate impact, and aggregate crushing in order to determine the optimal proportion blend. As a result, the overall findings offer great application potential in the development of concrete (GCLA). It has been determined that aggregates with a toughness of 14.6% and a hardness of 15.9% are robust. The compressive strength test found that the GCLA has a high strength lightweight concrete of 37.19 MPa and a density of 1845.74 kg/m3. The porous features developed inside the internal structure of GLA have led to GCLA’s less weight compared to conventional concrete.

2

Properties and Morphology of Fly Ash Based Alkali Activated Material (AAM) Paste Under Steam Curing Condition

Razak Rafiza Abd, Izman Sharifah Nur Syamimi Syed, Abdullah Mohd Mustafa Al Bakri, Yahya Zarina, Abdullah Alida, Mohamed Rosnita

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 2

785--789

EN

This paper details the properties, microstructures, and morphologies of the fly ash-based alkali-activated material (AAM), also known as geopolymers, under various steam curing temperatures. The steam curing temperature result in subsequent high strengths relative to average curing temperatures. However, detailed studies involving the use of steam curing for AAM remain scarce. The AAM paste was prepared by mixing fly ash with an alkali activator consisting of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH). The sample was steam cured at 50°C, 60°C, 70°C, and 80°C, and the fresh paste was tested for its setting time. The sample also prepared for compressive strength, density, and water absorption testings. It was observed that the fastest time for the fly ash geopolymer to start hardening was at 80°C at only 10 minutes due to the elevated temperature quickening the hydration of the paste. The compressive strength of the AAM increased with increasing curing time from 3 days to 28 days. The AAM’s highest compressive strength was 61 MPa when the sample was steam cured at 50°C for 28 days. The density of AAM was determined to be ~2122 2187 kg/m3, while its water absorption was ~6.72-8.82%. The phase analyses showed the presence of quartz, srebrodolskite, fayalite, and hematite, which indirectly confirms Fe and Ca’s role in the hydration of AAM. The morphology of AAM steam-cured at 50°C showed small amounts of unreacted fly ash and a denser matrix, which resulted in high compressive strength.

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Influence of Salinity of Mixing Water Towards Physical and Mechanical Properties of High Strength Concrete

Razak Rafiza Abd, Yen Ng Khai, Abdullah Mohd Mustafa Al Bakri, Yahya Zarina, Mohamed Rosnita, Muthusamy Khairunisa, Jusoh Wan Amizah Wan, Nabiałek Marcin, Jeż Bartłomiej

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 3

1041--1045

EN

Dramatic population and economic growth result in increasing demand for concrete infrastructure, which leads to an increment of freshwater demand and a reduction of freshwater resources. However, freshwater is a finite resource, which means that freshwater will be used up someday in the future when freshwater demand keeps increasing while freshwater resources are limited. Therefore, replacing freshwater with seawater in concrete blending seems potentially beneficial for maintaining the freshwater resources as well as advantageous alternatives to the construction work near the sea. There have been few experimental research on the effect of blending water salt content on the mechanical and physical characteristics of concrete, particularly high-strength concrete. Therefore, a research study on the influence of salt concentration of blending water on the physical and mechanical properties of high-strength concrete is necessary. This study covered the blending water salinity, which varied from 17.5 g/L to 52.5 g/L and was determined on the physical and mechanical properties, including workability, density, compressive strength, and flexural strength. The test results indicate that the use of sea salt in blending water had a slight negative influence on both the workability and the density of high strength concrete. It also indicates that the use of sea salt in blending water had a positive influence on both the compressive strength and the flexural strength of high-strength concrete in an earlystage.

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The Investigation of Ground Granulated Blast Furnace Slag Geopolymer at High Temperature by Using Electron Backscatter Diffraction Analysis

Aziz Ikmal Hakem, Al Bakri Abdullah Mohd Mustafa, Salleh Mohd Arif Anuar Mohd, Yoriya Sorachon, Razak Rafiza Abd, Mohamed Rosnita, Baltatu Madalina Simona

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 1

227--231

EN

This paper elucidated the potential of electron backscatter diffraction analysis for ground granulated blast furnace slag geopolymers at 1000°C heating temperature. The specimen was prepared through the mechanical ground with sandpaper and diamond pad before polished with diamond suspension. By using advanced technique electron backscatter diffraction, the microstructure analysis and elemental distribution were mapped. The details on the crystalline minerals, including gehlenite, mayenite, tobermorite and calcite were easily traced. Moreover, the experimental Kikuchi diffraction patterns were utilized to generate a self-consistent reference for the electron backscatter diffraction pattern matching. From the electron backscatter diffraction, the locally varying crystal orientation in slag geopolymers sample of monoclinic crystal observed in hedenbergite, orthorhombic crystal in tobermorite and hexagonal crystal in calcite at 1000°C heating temperature.

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Marshall stability of porous asphalt mixture incorporating kenaf fiber

Jasni Nur Ezreen, Masri Khairi Azman, Jaya Ramadhansyah Putra, Abdullah Mohd Mustafa Al Bakri, Razak Rafiza Abd, Nabiałek Marcin, Błoch Katarzyna, Śliwa Agata

Archives of Civil Engineering

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2022

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Vol. 68, nr 1

379--393

EN

Porous asphalt mixture (PA), known as open-graded surfaces over a stone bed underneath, allows water to go through. These factors can affect the porous asphalt mixture adhesive strength. The high amount of course aggregate promotes the structure of air voids have certain impacts on the acoustic properties of porous asphalt. The materials properties are consisting of both aggregate and bitumen tests. This study also details out the aggregates sieve analysis test to develop new aggregate gradation for PA. According to five ASEAN countries’ specifications, the sieve analysis test was done. The countries included are Malaysia, Vietnam, Thailand, Singapore, and Indonesia. The test for the binder includes the softening point, penetration, and ductility. This study also investigates the addition of kenaf fiber in the mixture as an additive. Mechanical performance test for PA using Marshall Stability test to identify the strength and the properties of the conventional PA with the addition of kenaf fiber compared to the new gradation of PA incorporating kenaf fiber. From the results, the addition of 0.3% kenaf modified PA improved the performance of PA in terms of Marshall Stability and volumetric properties.

6

Effect of Rice Straw Ash (RSA) as partially replacement of cement toward fire resistance of self-compacting concrete

Razak Rafiza Abd, Chin Yi Qin, Abdullah Mohd Mustafa Al Bakri, Yahya Zarina, Ishak Mokhzani Khair, Garus Sebastian, Nabiałek Marcin, Zailani Warid Wazien Ahmad, Masri Khairil Azman, Sandu Andrei Victor, Śliwa Agata

Archives of Civil Engineering

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2022

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Vol. 68, nr 1

353--363

EN

Malaysia’s construction industry is experiencing rapid growth, translating into increased demand for cement. However, cement production pollutes the air to the detriment of the climate via CO2 emission, making research into a cementitious replacement in concrete a necessity. This paper details an experimental study of self-compacting concrete (SCC) with partial replacement of cement by rice straw ash (RSA), which is expected to result in environmental preservation due to the green materials being used in cement production. The physicomechanical properties of the SCC with RSA replacement were determined via its compressive strength, water absorption, self-workability, and fire resistance (residual strength after exposure to high temperatures). The proportion of RSA replacement used were 0%, 5%, 10%, 15%, 20%, and 25%, and all passed the slump flow test, except the 20% and 25% samples. The SCC samples with 15% of RSA replacement reported the highest compressive strength at 7 and 28 curing days and the highest residual strength post-exposure to high temperatures. The lowest percentage of water absorption was reported by the 15% of RSA replacement, with a density of 2370 kg/m3