Pendentives and Squinches
- Groin Vault. The Romans, the first true masters of arched construction, developed the groin vault to overcome the limitations of the tunnel vault (see Roman Architecture ).
- Squinch. Instead of a groin vault, this supportive framework can alternatively be covered with a dome. ...
- Pendentive. ...
What is the difference between squinch and pendentive bridges?
The squinch has to be achieved by building a short bridge across each corner of a square structure, either by a system of corbelling (with projecting courses of stone or brick) or by constructing a small arch. The pendentive is a much more sophisticated concept, simpler in appearance but more complex in its geometry.
What is the difference between a pendentive and a square dome?
The use of four squinches turns a square into an octagon to support the dome, but they have a blocky appearance. A pendentive is more elegant, like a spherical triangle.
How do you make a squinch in architecture?
The squinch is achieved by building a short bridge across each corner of a square to transform the base of the dome into an octagon. This can either be achieved by a system of corbelling or by constructing a small arch. Pendentives: A curved triangle that connect the space between the arches and walls.
What is a squinch dome?
Though squinches solve the problem of connecting a dome to a square frame, a much more elegant solution was developed by the Byzantines. Instead of building ordinary walls above the four-arch frame, they filled the spaces between the arches with walls in the shape of spherical triangles. Each of these walls is called a pendentive. 1
What is squinch system?
squinch, in architecture, any of several devices by which a square or polygonal room has its upper corners filled in to form a support for a dome: by corbelling out the courses of masonry, each course projecting slightly beyond the one below; by building one or more arches diagonally across the corner; by building in ...
What does a pendentive do?
Pendentive is the term given to a construction element that allows a dome to be placed over square or rectangular spaces. Pendentives are triangular segments of a sphere that spread at the top and taper to points at the bottom, thereby enabling the continuous circular or elliptical base needed to support the dome.
Does the pantheon have Squinches?
The Romans were the first to truly master arched construction. A dome construction either demanded that the supporting structure is round, such as in Rome's Pantheon, or are supported on a square base by using a squinch or a pendentive. The squinch is the simpler of the two.
What is a complete pendentive?
pendentive, in architecture, a triangular segment of a spherical surface, filling in the upper corners of a room, in order to form, at the top, a circular support for a dome.
Did the Romans use pendentives?
Although rarely used, the pendentive dome was known in 2nd century Roman architecture and possibly earlier, in funerary monuments such as the Sedia dei Diavolo and the Torracio della Secchina on the Via Nomentana. Pendentive domes would be used much more widely in the Byzantine period.
What is the top of a dome called?
crownApex: The uppermost point of a dome (also known as the 'crown'). Cupola: A small dome located on a roof or turret. Extrados: The outer curve of a dome. Haunch: Part of an arch that that lies roughly halfway between the base and the top.
Is Hagia Sophia bigger than Pantheon?
The Hagia Sophia's original dome, which collapsed in 559, was thought to be slightly bigger in diameter but shallower than the current one, built in 563. Even so, the Hagia Sophia's dome today is 102 feet in diameter — just 40 feet smaller than the Pantheon's.
What is the drum of the Pantheon?
The Drum. The drum of the Pantheon is an immense structure, roughly 108 feet (32.2 m) tall and 21 feet (6.2 m) in thickness at the base, reducing to 20 feet (5.9 m) at the top. The ratio of the drum to the dome (44.08 m) is about 1 to 7.3.
What is Muqarnas vault?
A form of decorative vaulting in Islamic architecture. In muqarnas, the surface of a vault or dome is subdivided into niche-like cells that have no load-bearing function. Also know as stalactite vaulting or honeycomb vaulting. Web resource here.
What do you call a room with a dome?
A rotunda (from Latin rotundus) is any building with a circular ground plan, and sometimes covered by a dome. It may also refer to a round room within a building (a famous example being the one below the dome of the United States Capitol in Washington, D.C.).
Whats an upside down dome called?
inverted dome | architecture | Britannica.
What was the purpose of the architectural feature called the pendentive within Byzantine churches?
Starting from approximately A.D. 500, architects in early Christian Byzantine era began utilizing pendentives to raise height and support the weight of big domes. Byzantine architecture developed around the Roman capital of Byzantium, later renamed Constantinople and today known as Istanbul.
Squinch: Concept and construction
Straight walls are erected on a square base, a dome is placed on the top of these four walls. This means that the load is transferred from the points the dome meets the walls i.e. the centre of the wall. A heavy structure like dome needs uniform weight distribution hence the load must be transferred through the corners of the square as well.
Pendentives: Concept and construction
Though squinches solved the problem of supporting the dome they the tended to have a blocky-chunky appearance, hence a much more elegant solution- pendentive was developed by the Byzantines. It is simpler in appearance but more complex in its geometry.
Evolution of Pendentives
During the Renaissance and the Baroque the preference for domed churches, especially in Roman Catholic Europe and Latin America, gave great importance to the pendentive. Pendentives are also frequently used in Islamic architecture. They are often decorated with stalactite work or as in Iran, with delicate ribbing.
Difference between Pendentives and Squinches
An arch in each of the corners of a square base that transforms the base of the dome into an octagon and allows the dome to rest on the square base.
What is the shape of a pendentive?
Instead of building ordinary wall s above the four-arch frame, they filled the spaces between the arches with walls in the shape of spherical triangles. Each of these walls is called a pendentive. 1
Can a supportive framework be covered with a dome?
Instead of a groin vault, this supportive framework can alternatively be covered with a dome. This presents the interesting technical challenge of connecting something round to something square, whether the dome is set directly on the supportive frame or raised upon a cylindrical drum.