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This article is a development of the main article Geopolymer. From a terminological point of view, geopolymer cement〔Davidovits, J., (1991), Geopolymers: Inorganic Polymeric New Materials, ''J. Thermal Analysis'', 37, 1633–1656. See also Chapter 24 in ''Geopolymer Chemistry and Applications'', Joseph Davidovits, Institut Géopolymère, Saint-Quentin, France, 2008, ISBN 9782951482050 (3rd ed., 2011).〕 is a binding system that hardens at room temperature, like regular Portland cement. If a geopolymer compound requires heat setting it may not be called geopolymer cement but rather geopolymer binder. Geopolymer cement is an innovative material and a real alternative to conventional Portland cement for use in transportation infrastructure, construction and offshore applications. It relies on minimally processed natural materials or industrial byproducts to significantly reduce its carbon footprint, while also being very resistant to many of the durability issues that can plague conventional concretes. Creating geopolymer cement requires an alumina silicate material, a user-friendly alkaline reagent〔See the examples at the Geopolymer Institute page http://www.geopolymer.org/applications/geopolymer-cement〕 (sodium or potassium soluble silicates with a molar ratio MR SiO2:M2O>1,65, M being Na or K) and water (See the definition for "user-friendly" reagent below). Room temperature hardening relies on the addition of calcium cations, essentially iron blast furnace slag. Geopolymer cements cure more rapidly than Portland-based cements. They gain most of their strength within 24 hours. However, they set slowly enough that they can be mixed at a batch plant and delivered in a concrete mixer. Geopolymer cement also has the ability to form a strong chemical bond with all kind of rock-based aggregates. On March 2010, the US Department of Transportation Federal Highway Administration released a TechBrief titled ''Geopolymer Concrete'' that states:〔http://www.fhwa.dot.gov/pavement/pub_details.cfm?id=665〕 ''The production of versatile, cost-effective geopolymer cements that can be mixed and hardened essentially like Portland cement represents a game changing advancement, revolutionizing the construction of transportation infrastructure and the building industry.'' ''Geopolymer concrete'' There is often confusion between the meanings of the two terms 'geopolymer cement' and 'geopolymer concrete'. A cement is a binder whereas concrete is the composite material resulting from the addition of cement to stone aggregates. In other words, to produce concrete one purchases cement (generally Portland cement or Geopolymer cement) and adds it to the concrete batch. Geopolymer chemistry was from the start aimed at manufacturing binders and cements for various types of applications. For example, the British company banah UK (www.banahuk.co.uk) sells its ''banah-Cem''™ as geopolymer cement, whereas the Australian company Zeobond (www.zeobond.com) markets its ''E-crete''™ as geopolymer concrete. == Portland cement chemistry vs Geopolymer cement chemistry == ''Left:'' hardening of Portland cement (P.C.) through hydration of calcium silicate into calcium di-silicate hydrate (CSH) and lime Ca(OH)2. ''Right:'' hardening (setting) of geopolymer cement (GP) through poly-condensation of potassium oligo-(sialate-siloxo) into potassium poly(sialate-siloxo) cross linked network. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Geopolymer cement」の詳細全文を読む スポンサード リンク
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