On the Sustainability of Architectural Structure in Cross-domed Types

Abstract

Medieval Georgian ecclesiastical architecture is characterized by a variety of architectural types. This is due to Georgia's rich local construction experience, early integration into the Christian world, and involvement in all stages of the development of architecture. The first architectural type to develop was the basilica. The domed theme has been leading since the 6th century. The types of tetraconch, triconch, free cross, and inscribed cross are united in the group of cross-domed temples. Their common feature is the representation of the cross in the plane and space. The cross is formed by arms spreading out on four sides from the square under the dome. The four sides of the dome square represent the four sides of the world, respectively, of earthly existence. The circle formed at the base of the dome crowning the building on the top of the square symbolizes eternity, infinity and the heavenly world.

The tetraconch, free cross, and triconch type simple specimens in terms of the architectural structure were built initially. Further started their transformation process, which led to the development of complex variants and provided the possibilities for the emergence of structural modification of a specific architectural type.

A review of the factual data makes it clear that the issue of sustainability of the architectural structure in cross-domed types in Georgia is multifaceted and each type has its own way of evolutionary development. The main feature remains unchanged such as the cross like solution since the cross provides the basis of the ideology and planning of these buildings.

The most important variation is observed in the triconch type, where a fundamentally new architectural and constructional approach was used in the form of supports under the dome, which created the conditions for the construction of large-scale buildings and the use of planning varieties (Oshki, Bagrati, Alaverdi).

The type of tetraconch is distinguished by the dynamic change of the structure, as a result of which the monuments with corner rooms (Mtskhetis Jvari-type monuments) and walk-around subgroups (Ishkhan, Bana) with distinctive architectural and artistic value were built. As for the type of free cross, it retained its original appearance for centuries (Eralaant-Sakdari, Samtsevrisi, Khotevi), but at the same time, a semi-free cross-type (Eni-Rabati, Ekeki, Ikvi) was formed, in which the side rooms were placed next to the sanctuary that caused ignoring the main characteristic of the type such as the Cross configuration.

A comparative analysis of these architectural types clearly reveals that there are two motivators for changing their structure: the arranging of pastophoriums and increasing the area. This factor leads to the identification of the architectural and constructional potential of each type and the formation of new subtypes.

A different picture is created by the type of the inscribed cross. It is characterized by structural resilience, as the issues characteristic for other types are resolved here from the outset and there is no need for modification. This is clearly shown by the very first cross type specimen, the Tsromi Temple, which is a typologically and architecturally distinctive monument.