No abstract

No abstract

Results of research on development of complex techniques of chemical, petrographic, Xray phase and X-ray diffraction methods of medieval lime mortars studying are presented in the article. 12 samples from New Afon, Abkhazia and one from v. Khoy, Chechnya, have been studied. Results of analyses have confirmed estimated dates of the second defense line of Anacopia fortress foundation within 570-580 y., reconstruction of Gate tower in 910-930 y. and entrance gate-the 950th y. The analysis of lime mortars from screen church near Anacopia (Akuach's temple) has given time of 650-680 y. Has been revealed that gate in citadel wall have been constructed at the end of II in AD, western tower of a citadel-680-690 y., reconstruction of the temple of Feodor has been made in 910-930 y. Data of results of a complex research of lime mortars are supported by the documents of the Roman period (2nd century AD), the Byzantine period of the end of the 6th century, construction activity of Abkhazian archonstsars in the VII-X centuries. In comparison, tower in village Khoy was built in 11 с. The offered methods of researches allow to reconsidering the developed approaches to studying of limy mortars and their dating. Keywords-Byzantine architecture and building technology; dating methods of architectural heritage objects I.

No abstract

Determining the age of ancient architectural and cultural monuments is a significant scientific problem. An approach based on the transformation of portlandite into calcite and subsequent recrystallization of calcite is considered, which allows for estimating the relative age of ancient brickworks for local groups of historic buildings based on the results of diffraction studies of powder samples of carbonate mortars and measurements of samples with a known age. This article presents the results of the study of lime mortars of ancient brickwork. Under natural conditions, the process of transformation of portlandite into calcite takes from 100 to 200 years. The rate of this process is influenced by temperature, humidity, peculiarities of interaction with carbon dioxide contained in the air, etc. Examples show that portlandite is completely transformed into calcite in masonry mortars of the 18th century and that portlandite is not found in older mortars. It was determined that after the transformation of portlandite into calcite, an increase in the degree of recrystallization of calcite is observed, which manifests itself in powder diffraction patterns in the relative broadening of the diffraction peak of calcite hkl 104. In a detailed study, an estimate of the peak width at half maximum (FWHM) associated with the degree of crystallinity is effective. The actual data are given, which show that in older lime mortars the degree of recrystallization of calcite is higher than in younger ones. This fact makes it possible to indirectly determine the relative age of brickwork and masonry of various buildings of architectural heritage, which is especially relevant for the objects with the use of lime mortars of the northern provinces of the Byzantine Oecumene and other periods of various cultures.