Characterization of ancient, byzantine and later historic mortars by thermal and X-ray diffraction techniques

Moropoulou, A; Bakolas, A; Bisbikou, K

dc.contributor.author	Moropoulou, A	en
dc.contributor.author	Bakolas, A	en
dc.contributor.author	Bisbikou, K	en
dc.date.accessioned	2014-03-01T01:10:53Z
dc.date.available	2014-03-01T01:10:53Z
dc.date.issued	1995	en
dc.identifier.issn	0040-6031	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/11469
dc.subject	Cementitious mortars	en
dc.subject	Crushed brick mortars	en
dc.subject	Gypsum mortars	en
dc.subject	Historic mortars	en
dc.subject	Hydraulicity	en
dc.subject	Modern cement mortars	en
dc.subject	Portlandite mortars	en
dc.subject	TG-DTG evaluation	en
dc.subject	Thermal transformation	en
dc.subject	Typical lime mortars	en
dc.subject.classification	Chemistry, Analytical	en
dc.subject.classification	Chemistry, Physical	en
dc.title	Characterization of ancient, byzantine and later historic mortars by thermal and X-ray diffraction techniques	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/0040-6031(95)02571-5	en
heal.identifier.secondary	http://dx.doi.org/10.1016/0040-6031(95)02571-5	en
heal.language	English	en
heal.publicationDate	1995	en
heal.abstract	The characterization of mortar properties can be accomplished by the use of thermal analysis. DTA can be used to identify various component materials and observe the reactions associated with controlled heating of the mortar. This method reveals thermal transformations, which include dehydration, dehydroxylation, oxidation and decomposition. In addition, crystalline transitions can be observed, which are exothermic or endothermic in nature. With TGA, thermogravimetric analysis, the mass of the sample is monitored (weight loss) as a function of temperature. Weight losses at reaction temperatures near 750°C, indicate loss of CO2 not from pure CaCO3, but from recarbonated lime. The dehydroxylated clays acted as a ""pozzolan"" which imparts early strength to the mortar. However, a more complex phenomenon occurs in crushed brick mortar, since compounds of hydraulic type occur at the brick matrix interface also. The DTA and TG-DTG analyses identify the dehydration of calcium alumino-silicate phases, giving clear evidence of a cementitious mortar rather than one of pure lime. In the present work a spectrum of thermal and XRD analysis results from ancient, Byzantine, post-Byzantine and later historic mortars from Greece is presented and the relevant information concerning the characterization of traditional mortars is validated. Generally, the CO2 bound to carbonates and the water bound to hydraulic components (in weight loss%) discern two groups of mortars, the typical lime and the hydraulic, respectively. The specific classification of mortars into groups with characteristic transformations indicated by weight loss against temperature, enables discernment of: typical lime, cementitious, with crushed brick, with portlandite, with gypsum, with modern cement or of hot lime technology, mortars. Mineralogical, microstructural, mechanical and technological data could provide further evaluation criteria. © 1995.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Thermochimica Acta	en
dc.identifier.doi	10.1016/0040-6031(95)02571-5	en
dc.identifier.isi	ISI:A1995TQ42700068	en
dc.identifier.volume	269-270	en
dc.identifier.issue	C	en
dc.identifier.spage	779	en
dc.identifier.epage	795	en