Corbel arch

Basic principle of corbeled arch design.
Comparison of a corbel arch (right) and a generic "true" stone arch (left).

A corbel arch (or corbeled / corbelled arch) is an arch-like construction method that uses the architectural technique of corbeling to span a space or void in a structure, such as an entranceway in a wall or as the span of a bridge. A corbel vault uses this technique to support the superstructure of a building's roof.

A corbel arch is constructed by offsetting successive courses of stone (or brick) at the springline of the walls so that they project towards the archway's center from each supporting side, until the courses meet at the apex of the archway (often, the last gap is bridged with a flat stone). For a corbeled vault covering the technique is extended in three dimensions along the lengths of two opposing walls.

Royal Palace of Ugarit Entrance

Although an improvement in load-bearing efficiency over the post and lintel design, corbeled arches are not entirely self-supporting structures, and the corbeled arch is sometimes termed a "false arch" for this reason. Unlike "true" arches, not all of the structure's tensile stresses caused by the weight of the superstructure are transformed into compressive stresses. Corbel arches and vaults require significantly thickened walls and an abutment of other stone or fill to counteract the effects of gravity, which otherwise would tend to collapse each side of the archway inwards.

Use in historical cultures

Ireland

The Newgrange passage tomb has an intact corbel arch (vault) supporting the roof of the main chamber, and the buildings of the monastery at Skellig Michael are constructed using this method.

Ancient Egypt

Egyptian pyramids from around the time of Sneferu used corbel vaults in some of their chambers. These include the Bent Pyramid and the Red Pyramid.

Ancient Mediterranean

Arches at Nuraghe Santu Antine, Sardinia, 19-18th centuries BC

Corbel arches and vaults are found in various places around the ancient Mediterranean. In particular, corbelled burial vaults constructed below the floor are found in Ebla in Syria, and in Tel Hazor, and Tel Megiddo in Israel.[1]

Ugarit also has corbelled constructions.

Nuraghe constructions in ancient Sardinia, dating back to 1900 BC, use similar corbel techniques. The use of Beehive tombs on the Iberian peninsula and elsewhere around the Mediterranean, going back to 3000 BC, is also similar.

Anatolia

Corbelled chamber with hieroglyphs in Hattusa

The Hittites in ancient Anatolia were also building corbelled vaults. The earliest ones date to the 16th century BC.

Some similarities are found between the Hittite and Mycenaean construction techniques. Yet the Hittite corbelled vaults are earlier by about 300 years.[2]

Greece

The "Treasury of Atreus".

The ruins of ancient Mycenae feature many corbel arches and vaults, the "Treasury of Atreus" being a prominent example. The Arkadiko Bridge is one of four Mycenean corbel arch bridges which are part of a former network of roads, designed to accommodate chariots, between Tiryns and Epidauros in the Peloponnese, in Greece. Dating to the Greek Bronze Age (13th century BC), it is one of the oldest arch bridges still in existence and use. The well-preserved hellenistic Eleutherna Bridge on Crete has an unusually large span of nearly 4 m.[3]

Maya civilization

Maya corbel arch at Cahal Pech.

Corbeled arches are a distinctive feature of certain pre-Columbian Mesoamerican constructions and historical/regional architectural styles, particularly in that of the Maya civilization. The prevalence of this spanning technique for entrances and vaults in Maya architecture is attested at a great many Maya archaeological sites, and is known from structures dating back to the Formative or Preclassic era. By the beginning of the Classic era (ca. 250 CE) corbeled vaults are a near-universal feature of building construction in the central Petén Basin region of the central Maya lowlands.[4]

India

A corbel arch at the tomb of Nasir ud din Mahmud,Ghori, New Delhi.

Before the true arch was introduced by the Mughals, the arches in Indian buildings were trabeated or corbelled. In North India in the state of Orissa, "the later temples at Bhubaneswar were built on the principle of corbelled vaulting, which is seen first in the porch of the Mukteswar [a temple said to epitomize North Indian architecture, circa 950 AD] and, technically speaking, no fundamental change occurred from this time onwards."[5] The tomb of Sultan Ghari is an example of a corbelled arch from 1231 AD, located in New Delhi, India.

Indonesia

Stone corbelled arches at Borobodur in Java, Indonesia. Note the "T"-shaped central stones.

The candi or temples of Indonesia which are constructed between 8th to 15th century, are made use of corbel arch technique to create a span opening for gate or inner chamber of the temple. The notable example of corbel arch in Indonesian classic temple architecture is the arches of Borobudur. The interlocking andesite stone blocks creating the corbel arch, is notable for its "T" formed lock on the center top of the corbel arch.

Cambodia

The corbel span of Spean Praptos, 12th century Cambodia.

All the temples in Angkor made use of the corbel arch, between the AD 9th and 12th centuries.

Gallery

See also

References

  1. ↑ Suzanne Richard (2003), Near Eastern Archaeology: A Reader.
  2. ↑ Ç. Maner (2012), Corbelled Vaults in Hittite and Mycenaean Fortification Architecture
  3. ↑ Nakassis, Athanassios (2000): "The Bridges of Ancient Eleutherna", The Annual of the British School at Athens, Vol. 95, pp. 353–365 (358)
  4. ↑ Coe (1987), p.65.
  5. ↑ Michael Edwardes, Indian Temples and Palaces, London: Hamlyn, 1969, p. 95.

External links

This article is issued from Wikipedia - version of the 11/15/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.