shapeshift
byzantine innovations
The corner of one of four pendatives that support the central dome at Hagia Sophia.
The dome of Hagia Sophia has spurred particular interest for many art historians and architects because of the innovative way the original architects envisioned the it. The dome is supported by pendentives which had never been used before the building of this structure. The pendentive enables the round dome to transition gracefully into the square shape of the piers below. The pendentives not only achieve a pleasing aesthetic quality, but they also restrain the lateral forces of the dome and allow the weight of the dome to flow downward.
Although this design stabilizes the dome and the surrounding walls and arches, the actual construction of the walls of Hagia Sophia weakened the overall structure. The bricklayers used more mortar than brick, which weakened the walls. The structure would have been more stable if the builders at least let the mortar cure before they began the next layer; however, they did not do this. When the dome was placed atop the building, the weight of the dome caused the walls to lean outward because of the wet mortar underneath. When Isidorus the Younger rebuilt the original dome, he had to first build up the interior of the walls so that they were vertical in order to support the weight of the new dome. Another probable change in the design of the dome when it was rebuilt was the actual height of the dome. Isidore the Younger raised the height of the dome by approximately twenty feet so that the lateral forces would not be as strong and the weight of the dome would flow more easily down the walls.
A second interesting fact about the original structure of the dome was how the architects were able to place forty windows around the base of the dome. Hagia Sophia is famous for the mystical quality of light that reflects everywhere in the interior of the nave, which gives the dome the appearance of hovering above the nave. This design is possible because the dome is shaped like a scalloped shell or the inside of an umbrella with ribs that extend from the top of the dome down to the base. These ribs allow the weight of the dome to flow between the windows, down the pendentives, and ultimately to the foundation.
The anomalies in the design of Hagia Sophia show how this structure is one of the most advanced and ambitious monuments of late antiquity. (wikipedia)
byzantine innovations
The corner of one of four pendatives that support the central dome at Hagia Sophia.
The dome of Hagia Sophia has spurred particular interest for many art historians and architects because of the innovative way the original architects envisioned the it. The dome is supported by pendentives which had never been used before the building of this structure. The pendentive enables the round dome to transition gracefully into the square shape of the piers below. The pendentives not only achieve a pleasing aesthetic quality, but they also restrain the lateral forces of the dome and allow the weight of the dome to flow downward.
Although this design stabilizes the dome and the surrounding walls and arches, the actual construction of the walls of Hagia Sophia weakened the overall structure. The bricklayers used more mortar than brick, which weakened the walls. The structure would have been more stable if the builders at least let the mortar cure before they began the next layer; however, they did not do this. When the dome was placed atop the building, the weight of the dome caused the walls to lean outward because of the wet mortar underneath. When Isidorus the Younger rebuilt the original dome, he had to first build up the interior of the walls so that they were vertical in order to support the weight of the new dome. Another probable change in the design of the dome when it was rebuilt was the actual height of the dome. Isidore the Younger raised the height of the dome by approximately twenty feet so that the lateral forces would not be as strong and the weight of the dome would flow more easily down the walls.
A second interesting fact about the original structure of the dome was how the architects were able to place forty windows around the base of the dome. Hagia Sophia is famous for the mystical quality of light that reflects everywhere in the interior of the nave, which gives the dome the appearance of hovering above the nave. This design is possible because the dome is shaped like a scalloped shell or the inside of an umbrella with ribs that extend from the top of the dome down to the base. These ribs allow the weight of the dome to flow between the windows, down the pendentives, and ultimately to the foundation.
The anomalies in the design of Hagia Sophia show how this structure is one of the most advanced and ambitious monuments of late antiquity. (wikipedia)