Study and analysis of the data of the architectural survey of Hagia Sophia

1998 Fiscal Year Final Research Report Summary

• Project/Area Number: 09650695
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Architectural history/design
• Research Institution: University of Tsukuba
• Principal Investigator: HIDAKA Kenichiro University of Tsukuba Institute of At and Design Associate Professor, 芸術学系, 助教授 (30144215)
• Co-Investigator(Kenkyū-buntansha): SATO Tatsuki Daido Institute of Technology Professor, 工学部, 教授 (40131148)
• Project Period (FY): 1997 – 1998
• Keywords: Dome / Hagia Sophia / Masonry structure / Photogrammetry

Research Abstract

The object of the research, carried on in parallel with the in-situ survey on the Hagia Sophia in 97 and 98, is to analyze the photogrammetric data relating to the inner surface of the upper structures of the monument. As far as the central dome is concerned, our analyses have shown the following points, while the analyses of the four great arches and two tympana are still in process.
1) The setting lines as we see on the upper surface of the dome cornice, incised during the reconstruction of the dome in the 6th century, consists of two segmental curves, the centers of which were separately positioned due to the outward inclinations and displacements mainly caused by the collapse of the first shallow dome. The displacement and deformation of the arc of the setting lines can be divided into two components : (1)a approximately parallel movement of the arc itself toward the outside, caused by the movements of the supporting structure in the same direction, and (2) deformation or the deviat ion of the arcs themselves due to the deformation of the cornice after its reconstruction in the 6th century. While the values, though with certain inaccuracy, relating to the first point were given by Van Nice, our analyses have given for the first time the second component which is important for further consideration of the deformation history of the structure.
2) The formal characteristics of the ribs and the vertical sections of the central dome has also been analyzed, comparing the digitized data of the photogrammetric survey with the reference semi-circle. In the 6th part, the shape of the vertical section deviates noticeably around the height of 53-55m from the ground level. The deviation shows the evident .trace of the collapse in the 10th and 14th century. The deviation is more clearly visible in the southern portion and becomes obvious toward the border of the reconstructed part. The portions of the 10th and 14th century, subsequently reconstructed after the partial collapse of these centuries, are markedly different in sectional shape in that their ribs have a irregular waving around the height of 45m.