Barrel vault

In medieval Europe, the barrel vault was an important element of stone construction in monasteries, castles, tower houses and other structures.

The technique probably evolved out of necessity to roof buildings with masonry elements such as bricks or stone blocks in areas where timber and wood were scarce.

[2] Recent archaeological evidence discovered at the Morgantina site (in the province of Enna) shows that the aboveground barrel vault was known and used in Hellenistic Sicily in 3rd century BC, indicating that the technique was also known to ancient Greeks.

[4] Barrel vaults were also used in the Late Harappan Cemetery H culture dated 1900 BC-1300 BC which formed the roof of the metal working furnace, the discovery was made by Vats in 1940 during excavation at Harappa.

Persians and Romans were the first to use this building method extensively on large-scale projects and were probably the first to use scaffolding to aid them in construction of vaults spanning over widths greater than anything seen before.

However, with the coming of the Renaissance and the Baroque style, and revived interest in art and architecture of antiquity, barrel vaulting was re-introduced on a truly grandiose scale, and employed in the construction of many famous buildings and churches, such as Basilica di Sant'Andrea di Mantova by Leone Battista Alberti, San Giorgio Maggiore by Andrea Palladio, and perhaps most glorious of all, St. Peter's Basilica in Rome, where a huge barrel vault spans the 27 m (89 ft)-wide nave.

For example, at Muchalls Castle in Scotland, adjacent walls to the barrel vaulted chambers are up to 4.6 m (15 ft) thick, adding the buttressing strength needed to secure the curved design.

Thus the Romanesque medieval builders had to resort to techniques of small windows, large buttresses, or other forms of interior wall cross-bracing to achieve the desired lighting outcomes.

Since 1996 structural engineers have applied Newtonian mechanics to calculate numeric stress loads for ancient stonework barrel vaults.

[11] These analyses have typically used a finite element algorithm to calculate gravity induced stresses from the self weight of an arched system.

While none of these applications rival the majesty of the ancient and Classical predecessors, they demonstrate the pervasiveness of the barrel vault as an architectural concept in contemporary times.