Dome
This article is about the building structural element. For the Japanese racing car constructor, see Dome (constructor) |
St Peter's Basilica (topped with a lantern), Rome |
A
dome is a common structural element of
architecture that resembles the hollow
upper half of a sphere. Domes do not have to be perfectly spherical in cross-section, however; a dome may be a section through an
ellipse. If the baseline is taken parallel to the shorter of an ellipse's two
diameters, a tall dome results, giving a sense of upward reach. A section across the longer axis results in a low dome, capping the volume instead. A very low dome is a
saucer dome (see below). All the surfaces of any dome are curved. A spectacular innovation, one that is at the heart of
Baroque style, is the
oval dome, which gives axial direction and movement to the space beneath it. Though the oval dome is identified with churches of
Bernini and
Borromini, the first oval dome was erected by
Vignola for a small chapel, Sant'Andrea in via Flaminia often called Sant'Andrea del Vignola, which was commissioned in 1552 by
Julius III, and finished the following year [
1], the biggest oval dome was built in the basilica of
Vicoforte by Francesco Gallo.
Domes that have been disproportionately influential in later architecture are those of the
Great Stupa in Sanchi,
Pantheon in Rome,
Hagia Sophia in Istanbul, and
Dome of the Rock in Jerusalem. In Western architecture, the most influential domes built since the Renaissance have been those of
St. Peter's Basilica in Rome and
Jules Hardouin-Mansart's dome at
Les Invalides in Paris. The dome of
St. Paul's Cathedral in London was the inspiration for the
United States Capitol in Washington, which in turn inspired domes of most of the US state capitols. See further influential domes below.
A cathedral is often referred to as a
duomo in Italian or "
dom" in German, not because so many are crowned with
crossing domes over the space where
transepts intersect the nave, but from the latin "domus", house, in this case the "domus dei", the house of God. A dome is a mark of palatial ambitions whenever it is seen crowning a residence. The first residential domes were seen in Nero's
Domus Aurea that covered the slope of the Palatine Hill, built after the Great Fire of Rome of AD 64 with a lavishness that scandalized the senatorial class.
In the 20th century, thin "eggshell" domes of pre-stressed concrete by architect-engineers such as
Nervi opened new directions in fluid vaulted spaces enclosed beaneath freeform domed space which now might be supported merely at points rather than in the traditional constricting ring.
A dome can be considered as an
arch which has been rotated around its vertical axis. As such, domes have a great deal of structural strength. A small dome can be constructed of ordinary
masonry, held together by friction and compressive forces. Larger domes built after
Brunelleschi's dome that triumphantly spanned the crossing of
Santa Maria del Fiore, the
duomo of Florence, have all been built as double domes, with inner and outer shells.
The concave triangular or trapezoidal sections of vaulting that provide the transition between a dome and the square base on which it is set and transfer the weight of the dome are called
pendentives. (A less sophisticated version of a pendentive is a
squinch.) Under the dome illustrated at left, the pendentives bear circular medallions in bas relief.
A half-dome forms the head of an
exedra or its smaller version, a
niche. In Late Antiquity, the exedra developed into the
apse, with separate developments in
Romanesque and
Byzantine practice.
Many domes are topped by a
lantern, a structure with openings (or windows) to admit light in the
cupola.
Many sports
stadiums are domed, especially in climates that have widely-variable summer and winter weather. The first such stadium was the
Astrodome in
Houston, Texas. A major improvement to the domed stadium was accomplished with the construction of
SkyDome in
Toronto, Ontario, the first domed stadium with a retractable roof.
|
Gandon's Four Courts, Dublin, with a saucer dome. |
Saucer dome
A
saucer dome is the architectural term used for a low pitched shallow dome. Described geometrically as being of circular base and a segmental (less than a semicircle) section.
Gaining in popularity from the
18th century onwards, the saucer dome is often a feature of interior design, viewed from below it resembles the shallow
concave shape of a
saucer. The dome itself being often contained in the space between
ceiling and
attic is invisible externally. These domes are usually decorated internally by ornate
plaster-work, occasionally they are
frescoed.
They are seen occasionally externally in
Byzantine churches and
mosques.
Onion dome
Main article: Onion dome.
The
onion dome resembles more than half of a sphere, exemplified by
Saint Basil's Cathedral in
Moscow and the
Taj Mahal. They are found mostly in eastern architecture, particularly in
Russia,
Turkey,
India, and the
Middle East.
In
architecture, a
cupola consists of a
dome-shaped ornamental structure located on top of a larger
roof or dome, often used as a lookout or to admit light and provide ventilation. The word comes, through
Italian, from the lower latin 'cupula' (classical latin 'cupella' from the greek 'kupellon') small cup (lat. 'cupa') indicating a vault resembling an upside down cup.
In some cases, the entire main roof of a tower or spire can form a single cupola. More frequently, however, the cupola comprises a smaller structure which sits on top of the main roof. If the cupola can be reached by climbing a
stairway inside the building, it is referred to as a
belvedere or
widow's walk. Some cupolas, called
lanterns, have small windows which illuminate the areas below.
In the
Greek revival architecture, often seen in older homes of
Upstate New York and Northern
Pennsylvania, especially in the
Finger Lakes region, cupolas are often seen as a small room that extends above the main roof line. They may be square, rectangular, octagonal or round. In local folklore, they are regarded as
Indian lookouts, but they may have also been created simply to offer a scenic view, which fits with the other name, belvedere, an Italian term denoting a
fair view.
The term cupola is also often used for a projection above the roof of a
barn, which is primarily there for ventilation purposes.
Listed in order of their completion:
*
3rd century BC -
The Great Stupa, Sanchi, India.
*
27 BC -
The Pantheon, Rome, Italy.
*
537 -
Hagia Sophia, Istanbul, Turkey.
*
691 -
Dome of the Rock,
Jerusalem.
*
1312 -
Dome of Soltaniyeh,
Iran.
*
1436 -
The Duomo, Florence, Italy.
*
1502 - The
Tempietto, Rome, Italy.
*
1557 -
Suleiman Mosque, Istanbul, Turkey.
*
1574 -
Selimiye Mosque, Edirne, Turkey.
*
1593 -
St. Peter's Basilica, Rome, Italy.
*
1616 -
The Blue Mosque, Istanbul, Turkey.
*
1653 - The
Taj Mahal, Agra, India.
*
1659 -
Gol Gumbaz, Bijapur Karnataka India.
*
1708 -
Les Invalides, Paris, France.
*
1708 -
St Paul's Cathedral, London, England.
*
1733 -
Basilica Regina Montis Regalis, Vicoforte, Italy.
*
1749 - The
Radcliffe Camera, Oxford, England.
*
1858 -
St Isaac's Cathedral, St Petersburg, Russia.
*
1850s - The
United States Capitol, Washington, DC, USA.
*
1965 - The
Astrodome, Houston, TX, USA.
*
1983 -
BC Place Stadium, Vancouver, BC, Canada.
*
1989 -
SkyDome aka
Roger's Centre , Toronto, ON, Canada.
*
2000 - The
Millennium Dome, London, England. (This is not a true dome as it is not self supporting.)
*
2000 -
The Eden Project, Cornwall, UK.
*
2006 - Dome at Los Silvestres, Abiquiu, New Mexico
*
2006 - Dome (Brendan Medeiros)
The
Xanadu House was a home that used the concept of domes heavily in its shape and design. The home was one of the first non-indigenous homes to use curved surfaces throughout the exterior and interior.
*
Geodesic dome*
Monolithic dome*
Cupola*
Concrete dome*
Doming technique*
Rotunda*
Dome (geology)*
Dome (mathematics)*
Dome (Slang)*
Gonbad*
The Dome of Brunelleschi, Florence virtual reality movie and pictures
