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civil engineering-->>Types of arches


Types of arches

With reference to the earlier post on arches, this one defines the various types of arches. Arches are constructed in four basic shapes that frame and support doors, windows, porches, and other wall openings:
  • Flat arch
  • Triangular arch
  • Round arch
  • Pointed arch

Flat arch

An arch having a horizontal intrados with voissoirs radiating from a centre below, often built with a slight camber to allow settling is called a flat or jack arch.
French arch: A flat arch with voissoirs inclined to the same angle at each side of the center. The mortar joints do not, therefore, radiate to a common centre. Not, technically, a proper arch, and of weak form.

Triangular arch

It is a primitive form of arch consisting of two stones laid diagonally to support each other over an opening. Hence, the span is limited by the size of the available material.

Corbel arch: A false arch formed by corbelling courses from each side of an opening until they meet at a midpoint, where a capstone is laid to complete the work. The stepped reveals may be removed but no arch action is affected.

Round arch

Round arches are generally single centred or four centred arches. Following are the various types of round arches:
Roman Arch: A Roman arch is a strong rounded arch with a semicircular intrados. There are several examples of Roman arches in ancient Roman structures.

Segmental Arch: An arch struck from one or more centers below the springing point, which forms a partial curve or eyebrow. This arch is so named because it formed from a segment of a circle. It is an extremely common form of arch both in stone and in brick.

Stilted Arch: An arch resting on imposts treated as downward continuations of the archivolt.
Bell Arch: An arch resting on two large corbels with curved faces.


Horse shoe Arch: An arch having an intrados that extends above the springing before narrowing to a rounded crown. Also known as Moorish arch.

Basket Handle: A three centred arch having a crown with a radius much greater than that of the outer pair of curves. Also called anse de panier.
Florentine Arch: An arch having its extrados struck from a centre further up the central vertical axis than that of the intrados.

Pointed Arch

Gothic Arch: A pointed arch especially having two centers and equal radii.


Lancent Arch: A pointed arch having two centers and radii greater than the span.
Drop/Depressed Arch: A pointed arch having two centers and radii less than the span.

Ogee Arch: A pointed arch, each haunch of which is double curve with the concave side uppermost.

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