The Hagia Sophia Dome - Case Study Example

THE HAGIA SOPHIA DOME Introduction The Byzantine Church of Hagia Sophia or Divine Wisdom in Istanbul, Turkey, stands atop the first hill at the tip of the historic peninsula, surrounded by the waters of three seas. It was built by Emperor Justinian I between 532 and 537. Constructed on a scale unprecedented in human history, the church is considered as the finest example of Byzantine architecture in the world. The grand dome of the basilica is believed to symbolize the infinity of the cosmos signified by the Holy Soul to which the church was dedicated. The ambitious design and the speed of construction made the structure unstable. The dome was reconstructed after earthquakes in 557, 859, 989, and 1344, and the church was restored after it was plundered during the Fourth Crusade in 1204. The holy structure was the center for Eastern Christianity from 360 to the Ottoman conquest of Constantinople in 1453, after which it was used as a mosque (ArchNet). This paper proposes to examine the main dome atop the Hagia Sophia: its structure, the method of construction, and the aesthetics of the feature. The architectural elements of the dome and its contributions to the building as a whole will be discussed. Discussion The Hagia Sophia is a combination of the basilical and domical traditions of the post-Roman world. The symbolism of the cross and the domed crown are integrated by a combination of magnificent Roman architecture and standard Byzantine church architecture (Grabar: 76, 96). The Hagia Sophia: Istanbul, Turkey (Turkey in photos) Hagia Sophia: exterior and elevation (About.com: 2008) Architecturally Hagia Sophia represented a major revolution in church construction in that it necessitated the implementation of new ideas in order to support the weight of the huge dome, which was a feat that was attempted for the first time. Since there was no steel to be used in construction at that time, huge roofs and domes had to be supported by massive pillars and walls. The dome is supported by massive triangular pendentives above four arches that are set upon stone piers along the central aisle. Each pier measures about 98 square meters at the base. The four arches carry the weight of the dome to the large piers at the corners of the square. Thus the walls below the arches have no supporting function at all. The transition from the square formed by the arches to the circular rim of the dome is achieved by spherical triangles called pendentives. Hence the entire unit forms a dome on pendentives. This method along with the new technique of using thin bricks embedded in mortar, permits the construction of taller, lighter and more economical domes than the older method of placing the dome on a round or polygonal base. Hagia Sophia is the earliest example of the dome on pendentives, on a massive scale, and it set the precedent to become the basic feature of Byzantine architecture, and of western architecture as well (Janson & Janson: 245). To the east and west are semi-domes that help support the entire structure as seen in the flying buttresses employed for Gothic cathedrals in Europe. The lower part of the dome contains 40 small windows which illuminate the massive oval nave below. Because this ring of windows goes all the way around, they give the dome itself an appearance of weightlessness. The vast, striking interior space of this building is a consequence of its daringly engineered structure. The arches on either side of the central space are filled in, the walls are fixed in at floor and gallery levels by columnaded arcades. Those at front and back are open to half domes that in turn open to smaller domed exedrae or niches. Thus, the geometry of the great central dome on pendentives can be understood as being a half spherical dome from which four segments have been cut away to convert it to a square needing support only at its four corners. The corners at Hagia Sophia are buttressed by the half domes at front and rear and by external solid masonry masses at either side (Pile: 53). Structural studies to determine the earthquake-worthiness of the Hagia Sophia in Istanbul have proved that the monuments static and dynamic behaviour depends very strongly on the mechanical, chemical and microstructural properties of the masonry mortars and bricks. The results show a decrease of 5 to 10% in the natural frequencies, as the amplitude of accelerations increase and returns to their initial values, due to the non-linear nature of the masonry (Cakmak et al: 125). The analysis of the historic mortars has indicated that energy absorption by the structure during an earthquake occurs without affecting the materials’ properties irreversibly, while the compatibility of the mortars to the original building units allows for continuous stresses and strains (Moropoulou et al: 603). Dome omitted to show pendentive (About.com) Close-up view of the great dome of Hagia Sophia (Sacred Destinations: 2005-06) The Hagia Sophias magnificent dome rises 184 feet or 56 metres in height from the floor of the church, which is equivalent to about 15 storeys. and spans a width of approximately 102 feet (31metres). Below the dome is a crown formed by forty equally spaced ribs and forty windows through which light filters into the glittering interior of the dome (Sacred Destinations, 2005-06). Interior view of the magnificent dome of the Hagia Sophia (Sacred Destinations: 2005-06) “The architectural form of Santa Sophia is concealed by the richness of decoration. The walls, from the ground up, are covered in identical manner. Plaques of red, yellow and green marble blend with the mosaics, and these are further embellished by the capitals, imposts, architraves and friezes” (Beazley: 180). The mosaics used to decorate the interior surfaces were based not only on religious subjects, but also on the emperor and other members of the imperial family; in the Byzantine period portrait art was highly advanced. Like most Byzantine churches, the dome originally featured a central medallion of Christ Pantocrator which was added in the second half of the 9th century. The center dome now displays a calligraphic medallion quoting the Light Verse, Quran 24:35 (Sacred Destinations: 2005-06). The mosaic images that lined Hagia Sophia were obliterated when the building became a mosque in accordance with the Islamic prohibition of the realistic representation of art (Pile: 55). Conclusion The Hagia Sophia has a colourful and extensive history, as it has successively been transformed into a church, a mosque, a monument and a museum. The grand dome with its immense size and architectural features, is seen to impact the vast spaces within the building in a unique way. The forty windows around the lower edge of the dome filter in plenty of natural light, and help to light up the inner dome and extensive inner area of the church, lending a glow to the mosaics and decorative elements. Further, the use of arches and pendentives with immensely sized buttressing piers was a unique feat, for the purpose of installing the circular-based dome on the square support formed by the arches. The fact that this mode of constructing the dome of the Hagia Sophia formed the precedent, and became an important part of Byzantine architecture, indicates the magnificence and aesthetics that were achieved in its creation. This paper has highlighted the unique architectural characteristics of the dome atop the Hagia Sophia in Istanbul, Turkey. The structure of the dome, the method of building it, and the aesthetic value of the construction have been examined. The Hagia Sophia is well renowned the world over as an architectural wonder, mainly because of the huge dome that appears to float in the air due to the ring of windows at its base, and the beauty of its interiors. It will remain as a triumph to Byzantine engineering, architecture and art, despite the many repairs and renovations that have been undertaken, after the dome’s partial damage resulting from earthquakes. ------------------------------ Works Cited About.com. Constantinople – Hagia Sophia dome system. Available at: http://atheism.about.com/library/FAQs/christian/blxtn_constan-hagia10.htm ArchNet. Hagia Sophia. Available at: http://archnet.org/library/sites/one-site.jsp?site_id=2966 Beazley, Mitchell. The world atlas of architecture. New York: Portland House. 1988. Cakmak, A.S., Moropoulou, A., Mullen, C.A. Interdisciplinary study of dynamic behaviour and earthquake response of Hagia Sophia. Soil Dynamics and Earthquake Engineering 14.9 (1995):125-133. Grabar, Oleg. Muqarnas: annual on Islamic art and architecture. The United States of America: Brill Publishers. 1987. GreatBuildings. Hagia Sophia. Available at: http://www.greatbuildings.com/buildings/Hagia_Sophia.html Janson, Horst W. & Janson, Anthony F. History of art. New Jersey: Prentice Hall. 2003. Moropoulou, A., Cakmak, A.S. & Lohvyn, N. Earthquake resistant construction techniques and materials on Byzantine monuments in Kiev. Soil dymanics and earthquake engineering 19 (2000): 603-615. Pile, John F. A history of interior design. United Kingdom: Lawrence King Publishing. 2005. Sacred Destinations. Picture of great dome of Hagia Sophia. 2005-2006. Available at: http://www.sacred-destinations.com/turkey/hagia-sophia-photos/exterior-dome-closeup-c-betts.jpg.html Sacred Destinations. Interior view of the great dome of Hagia Sophia. 2005-2006. Available at: http://www.sacred-destinations.com/turkey/hagia-sophia-photos/dome-c-helen-betts.JPG.html Turkey in photos. Hagia Sophia travel guide. Available at: http://www.turkeyinphotos.com/index.html Read More