Study of early hydration of cement pastes containing alternative calcium sulfate bearing materials

Tzouvalas, G; Papageorgiou, A; Tsimas, S; Papageorgio, D

dc.contributor.author	Tzouvalas, G	en
dc.contributor.author	Papageorgiou, A	en
dc.contributor.author	Tsimas, S	en
dc.contributor.author	Papageorgio, D	en
dc.date.accessioned	2014-03-01T02:50:12Z
dc.date.available	2014-03-01T02:50:12Z
dc.date.issued	2005	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/34956
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-33645307108&partnerID=40&md5=d3d812bc2014d5ea5ad2a6ed6990db9d	en
dc.subject	Anhydrite	en
dc.subject	Ettringite	en
dc.subject	FGD	en
dc.subject	Gypsum	en
dc.subject	Induction / dormant period	en
dc.subject	Setting	en
dc.subject.other	Anhydrite	en
dc.subject.other	Ettringite	en
dc.subject.other	Induction / dormant period	en
dc.subject.other	Byproducts	en
dc.subject.other	Calcium compounds	en
dc.subject.other	Functionally graded materials	en
dc.subject.other	Gypsum	en
dc.subject.other	Setting	en
dc.subject.other	Cements	en
dc.title	Study of early hydration of cement pastes containing alternative calcium sulfate bearing materials	en
heal.type	conferenceItem	en
heal.publicationDate	2005	en
heal.abstract	The majority of cement plants mainly uses natural gypsum (CaSO4·2H2O) to regulate cement setting. The partial or total replacement of gypsum by materials, which contain calcium sulfate, has been instigated either by the increasing availability of low-cost by-products containing calcium sulfate or by the possibility that quarries would mine rock that is a mixture of gypsum and anhydrite. This paper is part of an extent research program aiming to investigate alternative calcium sulfate bearing materials, such as anhydrite and FGD gypsum. These materials have been examined in order to study the influence of their addition in cement physicomechanical properties (compressive strength, setting time). Hydration of cement pastes containing these CSBM was interrupted at specific time intervals within 5 min to 12 hours, and cement-setting reactions were characterized with the use of DTA, isothermal calorimetry and ESEM. In the same time SO32-, Ca2+ and pH of the pore solution were also evaluated. It is concluded that, compared with natural gypsum, FGD gypsum prolongs the dormant period of hydration, while anhydrite accelerates it. Moreover, at a specific hydration time, cements with FGD gypsum seem to form more ettringite than natural gypsum and anhydrite does.	en
heal.journalName	Proceedings of the International Conference on Achieving Sustainability in Construction	en
dc.identifier.spage	41	en
dc.identifier.epage	51	en