Pendentive

In architecture, a pendentive is a constructional device permitting the placing of a circular dome over a square room or of an elliptical dome over a rectangular room. The pendentives, which are triangular segments of a sphere, taper to points at the bottom and spread at the top to establish the continuous circular or elliptical base needed for a dome. In masonry the pendentives thus receive the weight of the dome, concentrating it at the four corners where it can be received by the piers beneath.

Schematic representation of a dome on pendentives.

Prior to the pendentive's development, builders used the device of corbelling or squinches in the corners of a room. Pendentives commonly occurred in Orthodox, Renaissance, and Baroque churches, with a drum with windows often inserted between the pendentives and the dome. The first experimentation with pendentives began with Roman dome construction in the 2nd–3rd century AD, while full development of the form came in the 6th-century Eastern Roman cathedral, Hagia Sophia, in Constantinople (Istanbul).

Gallery

• 
  A pendentive, labelled A. Illustration of a church in Nantua.
• 
  Formation of a pendentive. Eugène Viollet-le-Duc, 1856
• 
  Pendentive structure
• 
  Arches (left and right), dome (top) and pendentive (centre) in Moscow Cathedral
• 
  Holy Trinity Church, Fulnek, Czech Republic
• 
  Church of St. Clement of Ohrid, Skopje, North Macedonia
• 
  One pendentive of the Hagia Sophia main dome
• 
  Pendentive of the Church of Saint Sava main dome, Belgrade, Serbia
• 
  Vision of St. John on Patmos (1520–1522, Correggio, San Giovanni Evangelista, Parma), part of which is painted on the pendentives
• 
  The attributes of Allah (God) in intrinsic Islamic calligraphy on the pendentives of Çamlıca Mosque, Istanbul

See also

• History of Italian Renaissance domes
• Spandrel – Space between a curved figure and a rectangular boundary

Sources

• Heinle, Erwin; Schlaich, Jörg (1996), Kuppeln aller Zeiten, aller Kulturen, Stuttgart, ISBN 3-421-03062-6{{citation}}: CS1 maint: location missing publisher (link)
• Rasch, Jürgen (1985), "Die Kuppel in der römischen Architektur. Entwicklung, Formgebung, Konstruktion", Architectura, vol. 15, pp. 117–139