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Overview on Valorization of Dredged Materials as Cementitious Resource
Published in Amine El Mahdi Safhi, Valorization of Dredged Sediments as Sustainable Construction Resources, 2022
Amine El Mahdi Safhi, Abdelhadi Bouchikhi, Hassan Ez-Zaki, Patrice Rivard
Geopolymer is one of the research trends in construction materials and can reduce up to 85% of CO2 emissions. Only a few studies have investigated the use of DMs in geopolymer, even though DMs are a rich source of aluminosilicate, which is the primary requirement to produce geopolymer. However, in-depth analyses were lacking, and more research should be done for a proper mix design and proper curing regime. The use of DMs for clinker production is very promising and enhances the incorporation rate of those materials. However, very few studies have been conducted in such valorization. A deeper investigation is needed in terms of the durability aspect and thermodynamic modeling.
Epoxy Nanocomposites Containing Hybrid Montmorillonite/Geopolymer Filler for Piping Application
Published in Ahalapitiya H. Jayatissa, Applications of Nanocomposites, 2022
Mat Daud, Azlin Fazlina Osman, Mohammad Firdaus Abu Hashim
Geopolymer is a new family type of thermosetting inorganic polymer resin (Song et al. 2013). It is a cementitious material formed by aluminosilicates produced predominantly silica (Si) and aluminum (Al) materials. Generally, the process of geopolymerization involves chemical reactions under highly alkaline conditions. The discovery of geopolymer-based materials contributes to excellent mechanical properties, high early strength, abrasion resistance and thermal stability that lead to many application fields such as ceramics, binder, matrices for hazardous waste stabilization, fire resistance and high tech materials. Currently, geopolymer-based composites have become popular among researchers in order to improve several properties of geopolymer materials such as brittleness and their low flexural strength in order to extend the limit of application in the structural field. The well-known method is by combining the geopolymer with organic polymers such as polyvinyl acetate, polypropylene, polyvinyl alcohol or water-soluble organic polymers (Colangelo et al. 2013). However, the organic polymer usually acts as an additive in geopolymer systems.
39K
Published in Guillaume Madelin, X-Nuclei Magnetic Resonance Imaging, 2022
Geopolymers. Geopolymers are inorganic, typically ceramic, materials that form long-range amorphous networks. They can be used commercially for fire- and heat-resistant coatings and adhesives, medicinal applications, high-temperature ceramics, and new cements for concrete. NMR can be used for characterizing these materials, an in particular 23Na magic angle spinning (MAS) NMR [11] and 39K NMR [12]. Duxson et al. [12] analyzed the presence of free potassium in the pore solution of geopolymeric gels prepared without sodium hydroxide and confirmed that K+ is incorporated into these materials in preference to Na+.
Sustainable cement alternatives utilizing geopolymer for use in full depth reclamation of asphalt pavements
Published in International Journal of Pavement Engineering, 2022
Omar Alsanusi Amer, Prasad Rangaraju, Harish Konduru, Haitham Zeddan Hussein
One common option that reduces cement consumption is to partially replace it with a quality supplementary cementitious material (SCM) such as fly ash. Another option that has been gaining some attention and could entirely replace cement in some applications is using alkali-activated materials or geopolymers. Geopolymer is based on the alkaline activation of aluminosilicate source materials. The most common precursors or source materials for geopolymer have been fly ash, slag, and metakaolin. In addition, ground glass fibers (GGF) have been shown to work well as SCM Rashidian-Dezfouli and Rangaraju (2017), Rashidian-Dezfouli et al. (2018), Amer et al. (2022) and as source material for geopolymer production Rashidian-Dezfouli et al. (2018). Although many studies have investigated different SCMs for utilization as a partial or complete cement replacement in FDR Wen et al. (2004), Amer and Rangaraju 2019, Wolfe et al.2009, only a few studies have focused on using the geopolymer-based full-depth base-soil stabilization Avirneni et al. (2016), Adhikari et al. (2018), Hoy et al. (2016).
Durability and microstructural studies on fly ash blended self-compacting geopolymer concrete
Published in European Journal of Environmental and Civil Engineering, 2021
Mahima Ganeshan, Sreevidya Venkataraman
Concept of geopolymer (GP) and its effect in construction industry has been known for long years implementing zero cement technology. Geopolymer concrete is commercialised in many countries like Australia and New Zealand, as a method to reduce pollution and utilising waste products effectively to follow the slogan, ‘Wealth from Waste’. Geopolymer is a product obtained through chemical reaction that takes place in material of geological origin or byproduct materials, such as fly ash, blast furnace slag (GGBS), rice husk ash, etc. along with alkaline liquids (sodium or potassium-based) (Vijaya Rangan, 2014). In 1999, Palomo et al. introduced geopolymer in concrete, by completely eliminating Ordinary Portlant Cement (OPC) and activating blast furnace slag using alkaline liquids (Palomo et al., 1999). However, in later works, low calcium fly ash was considered to be beneficial in geopolymer feedstock material due to its high reactivity, economy and wide availability in industry. Heat curing method was adopted for most of the works to trigger the geopolymerisation that achieved sufficient strength in just three days after casting (Hardjito & Vijaya Rangan, 2005).
Evaluation of municipal solid waste incineration fly ash based geopolymer for stabilised recycled concrete aggregate as road material
Published in Road Materials and Pavement Design, 2021
Wisitsak Tabyang, Cherdsak Suksiripattanapong, Chayakrit Phetchuay, Chuthamat Laksanakit, Nuntachai Chusilp
Geopolymer is considered an environmentally low-carbon cementitious material. Current research works indicate that aluminosilicate-rich materials such as fly ash (FA) (Chindaprasirt et al., 2007; Phetchuay et al., 2014, 2016; Phummiphan et al., 2016; Sukmak et al., 2013, 2017; Sukprasert et al., 2019), bottom ash (BA) (Chindaprasirt et al., 2009; Suksiripattanapong et al., 2020), rice husk ash (RHA) (Suksiripattanapong et al., 2017), and municipal solid waste incineration bottom ash (Wongsa et al., 2017) can be used as a precursor for geopolymer. Recently, Poltue et al. (2019) investigated the strength properties of RCA stabilised with FA and RHA based geopolymer as pavement base material. Based on the strength requirement specified by the Thailand national road authorities (DOH, 2013; DRR, 2013), the optimal ingredient of RCA stabilised with FA-RHA geopolymer was found at the RHA/FA of 60/40 and NaOH/Na2SiO3 of 50/50. The excessive RHA caused high Si gels, which could hinder water evaporation resulting in a reduction of strength (Poltue et al., 2019).