Article
Construction & Building Technology
Yaping Ge, Xiang Tian, Dunwen Huang, Qingyu Zhong, Yiwei Yang, Hui Peng
Summary: Efflorescence behavior and compressive strength evolution were analyzed for metakaolin (MK)-based geopolymers cured at different temperatures and times. The influence of pore structure on efflorescence behavior and compressive strength evolution was identified based on pore structure characterization using MIP. The results showed that long-term and initial high-temperature curing had negative effects on efflorescence mitigation, with long-term curing facilitating alkali salt migration to the surface and initial high-temperature curing enhancing alkali salt movement by increasing pore connectivity. The number of pores below 20 nm governed the effect of efflorescence on compressive strength, with crystallization degrading geopolymer with a large number of pores below 20 nm. This study provides important insights into the effect of pore structure on efflorescence and compressive strength evolution, and facilitates the optimization of geopolymer formulations to alleviate efflorescence.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Construction & Building Technology
Pilomeena Arokiasamy, Mohd Mustafa Al Bakri Abdullah, Shayfull Zamree Abd Rahim, Mohd Remy Rozainy Mohd Arif Zainol, Mohd Arif Anuar Mohd Salleh, Marwan Kheimi, Jitrin Chaiprapa, Andrei Victor Sandu, Petrica Vizureanu, Rafiza Abdul Razak, Noorina Hidayu Jamil
Summary: Activated carbon has been a popular choice for heavy metal removal, but its amorphous structure and high cost have limited its performance. This study focuses on the synthesis of low-cost geopolymers using industrial sludge and metakaolin for improved heavy metal adsorption. The experimental results demonstrate that the synthesized geopolymers with lower solid to liquid ratio achieved the highest removal efficiency for copper.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Green & Sustainable Science & Technology
Sibel Tunali Akar, Hilal Colo, Fatih Sayin, Ilknur Kara, Tamer Akar
Summary: The study demonstrates that metakaolin-based geopolymer is an effective and environmentally friendly adsorbent for the removal of Cu(II) ions from contaminated water.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Construction & Building Technology
Junxia Li, Bernie Wee Yuan Tay, Jiawei Lei, En-Hua Yang
Summary: This study examines the Seebeck effect of metakaolin-based geopolymer, showing high Seebeck coefficient and superior thermoelectric figure of merit, indicating its potential for use as a thermoelectric material.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Review
Environmental Sciences
Bharat Bhushan Jindal, Thamer Alomayri, Assaedi Hasan, Cyriaque Rodrigue Kaze
Summary: In the past three decades, the demand for sustainable and environmentally friendly concrete has led to the development of low carbon concretes such as geopolymer concrete. Metakaolin, commonly used as an additive or replacement for cement, has been investigated as a precursor in geopolymer concrete due to its effective pozzolanic properties. Various studies have examined the effects of metakaolin on the properties of geopolymer concrete, including factors such as alkali content, solids/liquids ratio, molar ratio, and curing regime. The findings generally suggest that metakaolin as a precursor produces better geopolymer products with improved durability and performance.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Construction & Building Technology
Yiping Luo, Zhonghua Jiang, Defa Wang, Yurong Lv, Cungen Gao, Guobin Xue
Summary: This study investigated the effects of NaOH on pore structure and mechanical properties of UMK geopolymers under room temperature curing conditions. The results showed that with increasing NaOH concentration, the porosity of UMK geopolymer decreased and large pores evolved into mesopores.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Polymer Science
Ximena Jaramillo-Fierro, Sneyder Gaona, John Ramon, Eduardo Valarezo
Summary: In this study, GP and GTA geopolymeric materials were prepared and characterized. The compounds showed high adsorption capacity and photocatalytic activity for the degradation of MB dye. The incorporation of ZnTiO3/TiO2 in the geopolymeric matrix allowed GTA to achieve higher overall efficiency compared to GP, combining adsorption and photocatalysis. The synthesized compounds could be used for multiple cycles for the removal of MB from wastewater.
Article
Construction & Building Technology
W. Sekkal, A. Zaoui
Summary: In the construction industry, the search for high thermal and sound insulation materials is crucial for reducing carbon footprints and energy consumption. Geopolymer nanocomposites are gaining attention as an alternative binder to Ordinary Portland Cement (OPC) due to their excellent properties including high strength, resistance to corrosion and abrasion, and ability to withstand heat and sound exposure. This study investigates the nanoscale analysis of geopolymer materials to enhance their insulation properties, considering factors such as porosity, nanopore size, moisture, and chemical composition. The findings suggest that geopolymer with a high-silicon content and sodium alkali activators exhibits better thermal isolation. Additionally, the presence of residual water significantly enhances the thermal insulation of highly nanoporous metakaolin geopolymer. Lastly, the nanoscale investigation shows that nano-porous geopolymer paste with pore size and porosity higher than 12 angstrom and 20% respectively has promising acoustic insulation properties, making it a great challenge for cementitious materials.
CEMENT & CONCRETE COMPOSITES
(2023)
Article
Construction & Building Technology
Guangwei Liang, Huajun Zhu, Haoxin Li, Tiejun Liu, Henghui Guo
Summary: The influences of rice husk ash (RHA) and silica fume (SF) on freezing resistance were investigated in this study. It was found that both RHA and SF can improve the pore structures and freezing resistance of metakaolin-based geopolymer, with RHA showing potential filling effect and SF acting more as an active supplementary material.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Ricarda Sposito, Matthias Maier, Nancy Beuntner, Karl-Christian Thienel
Summary: The study compares the impact of blending different cementitious systems with calcined clays for the first time, and explores the role of tailor-made PCE in regulating flowability and early strength development.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Review
Construction & Building Technology
Shikun Chen, Shengqian Ruan, Qiang Zeng, Yi Liu, Mingzhong Zhang, Ye Tian, Dongming Yan
Summary: This paper reviews the studies on the pore structure of geopolymers, focusing on its relationship with material performance and influencing factors. It provides general rules for optimizing the pore structure and performance of geopolymers, aiding in their rational design and application.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Green & Sustainable Science & Technology
Chan Juan Li, Yao Jun Zhang, Hao Chen, Pan Yang He, Qian Meng
Summary: In this paper, a cost-effective hierarchical pore geopolymer based on solid waste was synthesized and showed excellent adsorption properties for removing methylene blue dye from wastewater. The acid-treated geopolymer particles exhibited a high specific surface area and microporosity, providing abundant adsorption sites for the dye. The optimal geopolymer adsorbent achieved a high adsorption efficiency and removal efficiency, and showed good regeneration performance and selectivity towards cationic dyes.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Materials Science, Ceramics
Alessandro Filipponi, Giulia Masi, Serena Bandini, Maria Chiara Bignozzi
Summary: This study investigates the use of one-part pressed geopolymers as a support for microfiltration membranes. The properties of these materials, including mineralogy, physical characteristics, microstructure, and hydraulic properties, are presented. The geopolymeric membrane flat supports were synthesized through pressing a dry-mixed powder and optimizing the mixing and pressing process. The results show that the geopolymers have high open porosity, pore diameter, and flexural strength, demonstrating their potential as microfiltration support.
CERAMICS INTERNATIONAL
(2023)
Article
Construction & Building Technology
Fatheali A. Shilar, Sharanabasava Ganachari, Veerabhadragouda B. Patil, I. Neelakanta Reddy, Jaesool Shim
Summary: This paper explores an unexplored area in geopolymer and develops high-performance concrete. The optimal percentages of slag and activators, such as potassium and calcium hydroxide ratio, in metakaolin-based geopolymer are investigated. Different proportions of geopolymer concrete are cast using alkaline to binder ratios of 0.25, 0.35, and 0.45 and tested at 7, 28, and 90 days. The fresh, mechanical properties, probability, matrix, and smoothening plot for modulus of elasticity of geopolymer are investigated. The Ishikawa diagram discusses cause-and-effect factors of geopolymer concrete. Geopolymer exhibits medium workability and mechanical properties, and shows excellent results compared to traditional concrete at 30% slag usage and a 0.35 ratio of A/B. The optimum mix for geopolymer concrete with 30% GGBS achieves maximum strength.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Zhuangzhuang Yao
Summary: This paper conducted an experimental study on the desorption law of coal particle gas in order to clarify the transport mechanism of coalbed methane. The time-varying characteristics of the diffusion coefficient during the process of coal particle gas desorption were analyzed, and a gas diffusion calculation model considering the time-varying diffusion coefficient was obtained. The influence of coal particles with different shapes on the gas desorption law was studied, and the corresponding analytical solutions were obtained. The research results have important practical significance for the optimization of coalbed methane content testing method and coal and gas outburst risk prediction.
Article
Construction & Building Technology
Kiyofumi Kurumisawa, Kazuko Haga, Masahito Shibata, Daisuke Hayashi
Summary: The diffusion coefficient of blended cement materials increases with leaching, approaching that of ordinary Portland cement after considerable leaching. The diffusion coefficient post-leaching shows a good correlation with pore volume, particularly for pore diameters of 50 nm or larger.
JOURNAL OF ADVANCED CONCRETE TECHNOLOGY
(2021)
Article
Construction & Building Technology
Ali Jamshidi, Greg White, Kiyofumi Kurumisawa
Summary: The article discussed the concepts, theories, and engineering properties of epoxy asphalt technology, highlighting its superior rheological properties and structural performance compared to traditional asphalt mixtures. However, concerns remain regarding recyclability, initial strength, and total cost of pavement construction.
ROAD MATERIALS AND PAVEMENT DESIGN
(2022)
Article
Energy & Fuels
Yukun Kong, Yufeng Song, Yiwei Weng, Kiyofumi Kurumisawa, Dongming Yan, Xiangming Zhou, Su Wang, Shaoqin Ruan
Summary: Carbonated cement pastes (CCP) were investigated as supplementary cementitious materials (SCMs)-like components in ordinary Portland cement (OPC) paste. The results showed that the CO2 sequestration level of CCP increased with the growth of CO2 pressure. However, the use of CCP as a replacement led to higher water demand and inferior workability and compressive strength compared to the control group.
GREENHOUSE GASES-SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Y. K. Kong, Y. Song, K. Kurumisawa, T. Wang, D. Yan, Q. Zeng, X. Zhou, S. Ruan
Summary: The study investigated the feasibility of using hydrated cement paste (HCP) as a CO2 sponge by carbonating, calcining, and re-carbonating the HCP. Through microstructural analysis, the study examined the capacity of CO2 sequestration and release via HCP, as well as the carbonation phases formed within the cement paste. Initial results showed that HCP could effectively sequester CO2 and release it during the re-carbonation process, with moisture playing a significant role in the efficiency of the process.
JOURNAL OF CO2 UTILIZATION
(2022)
Article
Construction & Building Technology
Ali Jamshidi, Greg White, Kiyofumi Kurumisawa
Summary: Epoxy asphalt mixture (EAM) is a relatively new material with good functional properties for flexible pavement and exhibits better field performance compared to traditional asphalt mixture. By studying the reliability of EAM and its application in different transportation infrastructure, the development of better performing pavements can be supported.
ROAD MATERIALS AND PAVEMENT DESIGN
(2023)
Article
Construction & Building Technology
Qi Zhai, Kiyofumi Kurumisawa
Summary: This study found that curing temperature and the nature of activators significantly affect the early strength, hydration degree, and microstructure of Ca(OH)(2)-activated GGBFS samples. Activators influence pore solution composition and pH value, with low pH and high Ca2+ activity inhibiting Ca(OH)(2) dissolution and GGBFS reaction. Elevated temperatures mainly accelerate GGBFS hydration at early stages in all samples.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Qi Zhai, Kiyofumi Kurumisawa
Summary: This study investigates the effects of different cations on the activation of blast-furnace slag. It is found that the type of sulfate significantly influences the hydration of slag. MgSO4's promotion of slag hydration is limited due to the precipitation of gypsum and brucite, while high concentration of sulfate ions promotes strength development. The pH increase in K2SO4 and Na2SO4 is due to synergistic reactions, while the low pH of MgSO4 inhibits slag dissolution.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Engineering, Civil
S. H. Chu, K. Kurumisawa, Y. K. Kong
Summary: This paper presents a quantitative analysis of the mechanical performance of ultra-high performance fiberreinforced concrete (UHPFRC) and establishes a mathematical model for strength prediction. It also constructs an artificial neural network model. The study provides useful guidelines for the mix design of sustainable and resilient UHPFRC.
ENGINEERING STRUCTURES
(2023)
Article
Green & Sustainable Science & Technology
Y. K. Kong, K. Kurumisawa, S. H. Chu
Summary: In this study, a comparative life cycle assessment (LCA) approach was used to analyze the environmental impacts of infilled cementitious composites (ICC) and ultra-high performance concrete (UHPC). ICC, developed based on fiber-particle packing theory, paste volume control, and UHPC technology, can help reduce the environmental impacts. The ecological impacts of ICC can be further mitigated by using supplementary cementitious materials and filler.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Construction & Building Technology
Y. K. Kong, Kiyofumi Kurumisawa
Summary: This study systematically evaluated and predicted the ultimate drying shrinkage of Alkali-activated materials (AAMs) using an artificial neural network model. The model showed high accuracy and generality, while other commonly used models for predicting drying shrinkage were also evaluated and compared. The findings contribute to a better understanding of the drying shrinkage behaviors of AAMs and provide practical guidelines for designing AAM mixtures with high durability.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Construction & Building Technology
Zhai Qi, Yibing Zuo, Kiyofumi Kurumisawa, Aoran Lang
Summary: This study investigated the effects of additional activators (sodium sulfate, sodium nitrite, and calcium nitrite) and curing temperature (20 and 35 degrees C) on the chloride binding and ingress resistance of ground granulated blast furnace slag activated by Ca (OH)2 using various analytical techniques. The results showed that the types of AFm phase had a significant impact on the chloride binding capacity at low chloride concentrations. The leaching of calcium ions and carbonation, induced by the coarse pore structure, resulted in a decrease in the chloride binding capacity at a curing temperature of 35 degrees C. The formation of a denser calcite layer at the exposure layer positively influenced the chloride ingress resistance.
CEMENT & CONCRETE COMPOSITES
(2023)
Review
Construction & Building Technology
Y. K. Kong, Kiyofumi Kurumisawa
Summary: Alkali-activated materials (AAMs) are gaining popularity as ecofriendly and sustainable construction materials for their ability to reduce carbon emissions and utilize industrial byproducts. However, their practical application is hindered by variability in their properties during the early stages. This study provides an overview of the fresh properties of AAMs and discusses the influence of material composition on workability and setting. It also proposes data fusion and image-based analysis as methods to address the limitations of fresh AAMs.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Construction & Building Technology
Y. K. Kong, Kiyofumi Kurumisawa
Summary: Alkali-activated materials (AAMs) have been extensively studied for their superior performance and eco-friendliness. However, the assessment of their fresh properties, which play a crucial role in their workability, has been overlooked in previous research. This study comprehensively evaluates the workability of different types of AAMs and constructs a mathematical model for predicting their flowability. The study provides practical guidelines for AAM mix design with high workability and consistency.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2023)
Article
Construction & Building Technology
Qi Zhai, Kiyofumi Kurumisawa, Juhyuk Moon
Summary: In this study, the impact of four accelerators on the hydration and strength development of blast furnace slag cement was investigated. The results showed that sodium sulfate effectively enhanced early age strength, while calcium nitrite had different effects at different temperatures. In addition, the use of TEA and DEIPA at 5 degrees Celsius was not recommended.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Engineering, Environmental
Y. K. Kong, S. Ruan, Kiyofumi Kurumisawa
Summary: In this study, calcined carbonated hydrated cement pastes (HCPs) were used to partially replace ordinary Portland cement (OPC) as a cementitious material. The initial results showed that the HCP could sequester CO2, forming various calcium carbonates. The 28-day compressive strength of the calcined carbonated HCP-OPC mixtures increased with the replacement ratio up to 20%, owing to the filler effect of wollastonite. By recycling demolition waste, this study proposed a technology roadmap for CCUS and conducted a life cycle assessment to evaluate and compare the environmental impacts.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)