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136-515: An arch functions as a curved lintel. In worldwide architecture of different eras and many cultures, a lintel has been an element of post and lintel construction. Many different building materials have been used for lintels. In classical Western architecture and construction methods, by Merriam-Webster definition, a lintel is a load-bearing member and is placed over an entranceway. The lintel may be called an architrave , but that term has alternative meanings that include more structure besides

272-480: A dromos entry. The inclusion of domes, however, represents a wider sense of the word vault. The distinction between the two is that a vault is essentially an arch which is extruded into the third dimension , whereas a dome is an arch revolved around its vertical axis . Pitched-brick vaults are named for their construction, the bricks are installed vertically (not radially) and are leaning (pitched) at an angle: This allows their construction to be completed without

408-567: A four-centred arch is made of two circle segments with distinct centers; usually the radius used closer to the springing point is smaller with a more pronounced curvature. Common in Islamic architecture ( Persian arch ), and, with upper portion flattened almost to straight lines ( Tudor arch ), in the English Perpendicular Gothic . A keel arch is a variant of four-centred arch with haunches almost straight, resembling

544-459: A catenary is often misclassified as a parabola (per Galileo , "the [hanging] chain fits its parabola almost perfectly" ). González et al. provide an example of Palau Güell , where researchers do not agree on classification of the arches or claim the prominence of parabolic arches, while the measurements show that just two of the 23 arches designed by Gaudi are actually parabolic. Three parabolic-looking curves in particular are of significance to

680-514: A collapse (the oldest arch still standing is at Ramesseum ). Sacred buildings exhibited either lintel design or corbelled arches. Arches were mostly missing in Egypt temples even after the Roman conquest , even though Egyptians thought of the arch as a spiritual shape and used it in the rock-cut tombs and portable shrines. Auguste Mariette suggested that this choice was based on a relative fragility of

816-405: A decorative pattern, primarily at the top of window openings. The corbel (also corbelled ) arch, made of two corbels meeting in the middle of the span, is a true arch in a sense of being able to carry a load, but it is false in a structural sense, as its components are subject to bending stress. The typical profile is not curved, but has triangular shape. Invented prior to the semicircular arch,

952-407: A fixed arch, a two-hinged arch, or a three-hinged arch. The fixed arch is most often used in reinforced concrete bridges and tunnels, which have short spans. Because it is subject to additional internal stress from thermal expansion and contraction, this kind of arch is statically indeterminate (the internal state is impossible to determine based on the external forces alone). The two-hinged arch

1088-420: A god. Lintels may also be used to reduce scattered radiation in medical applications. For example, Medical linacs operating at high energies will produce activated neutrons which will be scattered outside the treatment bunker maze with a dose rate that depends on the maze cross section. Lintels may be visible or recessed in the roof of the facility, and reduce dose rate in publicly accessible areas by reducing

1224-399: A hemispherical dome is cut by four vertical planes, the intersection gives four semicircular arches; if cut in addition by a horizontal plane tangent to the top of these arches, it describes a circle; that portion of the sphere which is below this circle and between the arches, forming a spherical spandrel , is the pendentive , and its radius is equal to the diagonal of the square on which

1360-898: A number of civilizations in the ancient Near East including the Levant , but their use was infrequent and mostly confined to underground structures, such as drains where the problem of lateral thrust is greatly diminished. An example of the latter would be the Nippur arch, built before 3800 BC, and dated by H. V. Hilprecht  (1859–1925) to even before 4000 BC. Rare exceptions are an arched mudbrick home doorway dated to c.  2000 BC from Tell Taya in Iraq and two Bronze Age arched Canaanite city gates, one at Ashkelon (dated to c.  1850 BC ), and one at Tel Dan (dated to c.  1750 BC ), both in modern-day Israel . An Elamite tomb dated 1500 BC from Haft Teppe contains

1496-671: A parabolic vault which is considered one of the earliest evidences of arches in Iran. The use of true arches in Egypt also originated in the 4th millennium BC (underground barrel vaults at the Dendera cemetery). Standing arches were known since at least the Third Dynasty , but very few examples survived, since the arches were mostly used in non-durable secular buildings and made of mud brick voussoirs that were not wedge-shaped, but simply held in place by mortar , and thus susceptible to

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1632-446: A peculiar twisting of the web, where the springing of the wall rib is at K: to these twisted surfaces the term ploughshare vaulting is given. One of the earliest examples of the introduction of the intermediate rib is found in the nave of Lincoln Cathedral , and there the ridge rib is not carried to the wall rib. It was soon found, however, that the construction of the web was much facilitated by additional ribs, and consequently there

1768-473: A rounded, not pointed, top. Common in Islamic architecture and Romanesque buildings influenced by it, it later became popular in the decorative motifs of the Late Gothic designs of Northern Europe. Each arc of an ogee arch consists of at least two circle segments (for a total of at least four), with the center of an upper circle being outside the extrados. After European appearance in the 13th century on

1904-548: A section view of a capsized ship. Popular in Islamic architecture, it can be also found in Europe, occasionally with a small ogee element at the top, so it is sometimes considered to be a variation of an ogee arch. Curtain arch (also known as inflexed arch , and, like the keel arch, usually decorative ) uses two (or more) drooping curves that join at the apex. Utilized as a dressing for windows and doors primarily in Saxony in

2040-459: A semicircle, is associated with Islamic architecture and was known in areas of Europe with Islamic influence ( Spain , Southern France , Italy ). Occasionally used in Gothics, it briefly enjoyed popularity as the entrance door treatment in the interwar England. A pointed arch consists of two (" two-centred arch " ) or more circle segments culminating in a point at the top. It originated in

2176-515: A series of domes carried on pendentives covered over the nave, the chief peculiarities of these domes being the fact that the arches carrying them form part of the pendentives, which are all built in horizontal courses. The intersecting and groined vault of the Romans was employed in the early Christian churches in Rome, but only over the aisles, which were comparatively of small span, but in these there

2312-536: A slight rise in the centre, so as to increase its strength; this enabled the French masons to dispense with the intermediate rib, which was not introduced by them till the 15th century, and then more as a decorative than a constructive feature, as the domical form given to the French web rendered unnecessary the ridge rib, which, with some few exceptions, exists only in England. In both English and French vaulting centering

2448-554: A span of 80 feet (24 m), more than twice that of an English cathedral , so that its construction both from the statical and economical point of view was of the greatest importance. The researches of M. Choisy ( L'Art de bâtir chez les Romains ), based on a minute examination of those portions of the vaults which still remain in situ , have shown that, on a comparatively slight centering, consisting of trusses placed about 10 feet (3.0 m) apart and covered with planks laid from truss to truss, were laid – to begin with – two layers of

2584-573: A supplementary rib across the church and between the transverse ribs. This resulted in what is known as a sexpartite, or six-celled vault , of which one of the earliest examples is found in the Abbaye-aux-Hommes at Caen . This church, built by William the Conqueror, was originally constructed to carry a timber roof only, but nearly a century later the upper part of the nave walls were partly rebuilt, in order that it might be covered with

2720-425: A vault. The immense size, however, of the square vault over the nave necessitated some additional support, so that an intermediate rib was thrown across the church, dividing the square compartment into six cells, and called the sexpartite vault The intermediate rib, however, had the disadvantage of partially obscuring one side of the clerestory windows, and it threw unequal weights on the alternate piers, so that in

2856-497: A vault: "what would remain of the tombs and temples of Egyptians today, if they had preferred the vault?" Mycenaean architecture utilized only the corbel arches in their beehive tombs with triangular openings. Mycenaeans had also built probably the oldest still standing stone-arch bridge in the world, Arkadiko Bridge , in Greece. As evidenced by their imitations of the parabolic arches, Hittites most likely were exposed to

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2992-521: Is a form of vaulting common in Islamic architecture . The 20th century saw great advances in reinforced concrete design. The advent of shell construction and the better mathematical understanding of hyperbolic paraboloids allowed very thin, strong vaults to be constructed with previously unseen shapes. The vaults in the Church of Saint Sava are made of prefabricated concrete boxes. They were built on

3128-493: Is a load-bearing arc with elements held together by compression. In much of the world introduction of the true arch was a result of European influence. The term false arch has few meanings. It is usually used to designate an arch that has no structural purpose, like a proscenium arch in theaters used to frame the performance for the spectators, but is also applied to corbelled and triangular arches that are not based on compression. A typical true masonry arch consists of

3264-508: Is another dome, (the dome that one sees from the inside), but of plaster supported by a wood frame. From the inside, one can easily assume that one is looking at the same vault that one sees from the outside. There are two distinctive "other ribbed vaults" (called "Karbandi" in Persian) in India which form no part of the development of European vaults, but have some unusual features; one carries

3400-470: Is due to the Romans . When two semicircular barrel vaults of the same diameter cross one another their intersection (a true ellipse) is known as a groin vault , down which the thrust of the vault is carried to the cross walls; if a series of two or more barrel vaults intersect one another, the weight is carried on to the piers at their intersection and the thrust is transmitted to the outer cross walls; thus in

3536-527: Is known as a squinch . There is one other remarkable vault, also built by Justinian, in the Church of the Saints Sergius and Bacchus in Constantinople. The central area of this church was octagonal on plan, and the dome is divided into sixteen compartments; of these eight consist of broad flat bands rising from the centre of each of the walls, and the alternate eight are concave cells over

3672-443: Is most often used to bridge long spans. This kind of arch has pinned connections at its base. Unlike that of the fixed arch, the pinned base can rotate, thus allowing the structure to move freely and compensate for the thermal expansion and contraction that changes in outdoor temperature cause. However, this can result in additional stresses, and therefore the two-hinged arch is also statically indeterminate, although not as much as

3808-409: Is one in which all of the groins are covered by ribs or diagonal ribs in the form of segmental arches. Their curvatures are defined by the bounding arches. Whilst the transverse arches retain the same semi-circular profile as their groin-vaulted counterparts, the longitudinal arches are pointed with both arcs having their centres on the impost line . This allows the latter to correspond more closely to

3944-648: Is surmised that to the top of the pendentives they were built in horizontal courses of brick, projecting one over the other, the projecting angles being cut off afterwards and covered with stucco in which the mosaics were embedded; this was the method employed in the erection of the Périgordian domes, to which we shall return; these, however, were of less diameter than those of the Hagia Sophia, being only about 40 to 60 feet (18 m) instead of 107 feet (33 m) The apotheosis of Byzantine architecture , in fact,

4080-571: Is the most common form of the pointed arch, with the centers of two circles forming the intrados coinciding with the springing points of the opposite segment. Together with the apex point, they form a equilateral triangle , thus the name. If the centers of circles are farther apart, the arch becomes a narrower and sharper lancet arch that appeared in France in the Early Gothic architecture ( Saint-Denis Abbey ) and became prominent in England in

4216-599: Is the one that frames the internal side of an opening in the external wall. Structurally, relieving arches (often blind or containing) can be used to take off load from some portions of the building (for example, to allow use of thinner exterior walls with larger window openings, or, as in the Roman Pantheon , to redirect the weight of the upper structures to particular strong points). Transverse arches , introduced in Carolingian architecture , are placed across

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4352-517: Is the only one of the symmetric wedge shape), and that efficiently uses the compressive strength of the masonry in the same manner as a curved arch and thus requires a mass of masonry on both sides to absorb the considerable lateral thrust. Used in the Roman architecture to imitate the Greek lintels, Islamic architecture, European medieval and Renaissance architecture. The flat arch is still being used as

4488-400: Is therefore statically determinate. It is most often used for spans of medial length, such as those of roofs of large buildings. Another advantage of the three-hinged arch is that the reaction of the pinned bases is more predictable than the one for the fixed arch, allowing shallow, bearing-type foundations in spans of medial length. In the three-hinged arch "thermal expansion and contraction of

4624-630: The Roman builders since the 4th century BC . It is considered to be the most common arch form, characteristic for Roman, Romanesque , and Renaissance architecture. A segmental arch , with a rounded shape that is less than a semicircle, is very old (the versions were cut in the rock in Ancient Egypt c. 2100 BC at Beni Hasan ). Since then it was occasionally used in Greek temples , utilized in Roman residential construction, Islamic architecture , and got popular as window pediments during

4760-654: The Santa Maria del Fiore in Florence , built by Filippo Brunelleschi , and Ferguson cites as an example the great dome of the church at Mousta in Malta , erected in the first half of the 19th century, which was built entirely without centering of any kind. It is important to note that whereas Roman vaults, like that of the Pantheon , and Byzantine vaults, like that at Hagia Sophia , were not protected from above (i.e.

4896-568: The Sumerians , possibly under the ziggurat at Nippur in Babylonia , which was built of fired bricks cemented with clay mortar . The earliest barrel vaults in ancient Egypt are thought to be those in the granaries built by the 19th dynasty Pharaoh Ramesses II , the ruins of which are behind the Ramesseum , at Thebes . The span was 12 feet (3.7 m) and the lower part of

5032-426: The dead load increases with a distance from the center. Unlike regular arches, the flat arch (also known as jack arch , lintel arch , straight arch , plate-bande ) is not curved. Instead, the arch is flat in profile and can be used under the same circumstances as lintel . However, lintels are subject to bending stress, while the flat arches are true arches, composed of irregular voussoir shapes (the keystone

5168-426: The lintel , especially in the masonry construction: with the same amount of material it can have larger span, carry more weight, and can be made from smaller and thus more manageable pieces. Their role in construction was diminished in the middle of the 19th century with introduction of the wrought iron (and later steel ): the high tensile strength of these new materials made long lintels possible. A true arch

5304-466: The nave to compartmentalize (together with longitudinal separating arches) the internal space into bays and support vaults . A diaphragm arch similarly goes in the transverse direction, but carries a section of wall on top. It is used to support or divide sections of the high roof. Strainer arches were built as an afterthought to prevent two adjacent supports from imploding due to miscalculation. Frequently they were made very decorative, with one of

5440-498: The tepidaria of the Thermae and in the basilica of Constantine , in order to bring the thrust well within the walls, the main barrel vault of the hall was brought forward on each side and rested on detached columns, which constituted the principal architectural decoration. In cases where the cross vaults intersecting were not of the same span as those of the main vault, the arches were either stilted so that their soffits might be of

5576-528: The 13th-14th centuries their appeared as parts of flying buttresses used to counteract the thrust of Gothic ribbed vaults . A central part of an arch can be raised on short vertical supports, creating a trefoil -like shouldered arch . The raised central part can vary all the way from a flat arch to ogee. The shouldered arches were used to decorate openings in Europe from medieval times to Late Gothic architecture , became common in Iranian architecture from

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5712-585: The 14th century BC from Mycenae. They were built regionally until modern times. The real vault construction with radially joined stones was already known to the Egyptians and Assyrians and was introduced into the building practice of the West by the Etruscans. The Romans in particular developed vault construction further and built barrel, cross and dome vaults. Some outstanding examples have survived in Rome, e.g.

5848-526: The 14th century, and were later adopted in the Ottoman Turkey . In a stilted arch (also surmounted ), the springing line is located above the imposts (on "stilts"). Known to Islamic architects by the 8th century, the technique was utilized to vertically align the apexes of arches of different dimensions in Romanesque and Gothic architecture. Stilting was useful for semicircular arches, where

5984-564: The Egyptian designs, but used the corbelled technique to build them. The Assyrians , also apparently under the Egyptian influence, adopted the true arch (with a slightly pointed profile) early in the 8th century. In ancient Persia , the Achaemenid Empire (550 BC–330 BC) built small barrel vaults (essentially a series of arches built together to form a hall) known as iwan , which became massive, monumental structures during

6120-480: The Islamic architecture, arrived in Europe in the second half of the 11th century ( Cluny Abbey ) and later became prominent in the Gothic architecture . The advantages of a pointed arch over a semicircular one are flexible ratio of span to rise and lower horizontal reaction at the base. This innovation allowed for taller and more closely spaced openings, which are typical of Gothic architecture. Equilateral arch

6256-409: The Late Gothic and early Renaissance buildings (late 15th to early 16th century), associated with Arnold von Westfalen  [ de ] . When the intrados has multiple concave segments, the arch is also called a draped arch or tented arch . A similar arch that uses a mixture of curved and straight segments or exhibits sharp turns between segments is a mixed-line arch . The popularity of

6392-500: The Nimrud sculptures, the chief difference being that, constructed in rubble stone and cemented with mortar, they still exist, though probably abandoned on the Islamic invasion in the 7th century. A groin vault is formed by the intersection of two or more barrel vaults, resulting in the formation of angles or groins along the lines of transition between the webs. In these bays the longer transverse arches are semi-circular, as are

6528-579: The Pantheon and the Basilica of Maxentius. Brick vaults have been used in Egypt since the early 3rd millennium BC. widely used and from the end of the 8th century B.C. Keystone vaults were built. However, monumental temple buildings of the pharaonic culture in the Nile Valley did not use vaults, since even the huge portals with widths of more than 7 meters were spanned with cut stone beams. Amongst

6664-480: The Renaissance. A basket-handle arch (also known as depressed arch , three-centred arch , basket arch ) consists of segments of three circles with origins at three different centers (sometimes uses five or seven segments, so can also be five-centred , etc.). Was used in late Gothic and Baroque architecture . A horseshoe arch (also known as keyhole arch ) has a rounded shape that includes more than

6800-422: The Roman brick (measuring nearly 2 feet (0.61 m) square and 2 in. thick); on these and on the trusses transverse rings of brick were built with longitudinal ties at intervals; on the brick layers and embedding the rings and cross ties concrete was thrown in horizontal layers, the haunches being filled in solid, and the surface sloped on either side and covered over with a tile roof of low pitch laid direct on

6936-542: The Roman reservoir at Baiae , known as the Piscina Mirabilis , a series of five aisles with semicircular barrel vaults are intersected by twelve cross aisles, the vaults being carried on 48 piers and thick external walls. The width of these aisles being only about 13 feet (4.0 m) there was no great difficulty in the construction of these vaults, but in the Roman Baths of Caracalla the tepidarium had

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7072-591: The Romans already replaced by small cupolas or domes. These domes, however, are of small dimensions when compared with that projected and carried out by Justinian in the Hagia Sophia . Previous to this the greatest dome was that of the Pantheon at Rome, but this was carried on an immense wall 20 feet (6.1 m) thick, and with the exception of small niches or recesses in the thickness of the wall could not be extended, so that Justinian apparently instructed his architect to provide an immense hemicycle or apse at

7208-402: The advantages of the arch, the vault and the dome. Vault (architecture) In architecture , a vault (French voûte , from Italian volta ) is a self-supporting arched form, usually of stone or brick, serving to cover a space with a ceiling or roof. As in building an arch, a temporary support is needed while rings of voussoirs are constructed and the rings placed in position. Until

7344-414: The aisles, and the other two partly by smaller arches in the apse, the thrust being carried to the outer walls, and to a certain extent by the side walls which were built under the arches. From the description given by Procopius we gather that the centering employed for the great arches consisted of a wall erected to support them during their erection. The construction of the pendentives is not known, but it

7480-550: The aisles, which had only half the span of the nave ; of this there is an interesting example in the Chapel of Saint John in the Tower of London – and sometimes by half-barrel vaults. The great thickness of the walls, however, required in such constructions would seem to have led to another solution of the problem of roofing over churches with incombustible material, viz. that which is found throughout Périgord and La Charente , where

7616-460: The angles of the octagon, which externally and internally give to the roof the appearance of an umbrella. Although the dome constitutes the principal characteristic of the Byzantine church, throughout Asia Minor are numerous examples in which the naves are vaulted with the semicircular barrel vault, and this is the type of vault found throughout the south of France in the 11th and 12th centuries,

7752-634: The angles, as in the Mosque of Damascus , which was built by Byzantine workmen for the Al-Walid I in CE 705; these gave an octagonal base on which the hemispherical dome rested; or again, as in the Sassanian palaces of Sarvestan and Firouzabad of the 4th and 5th century, when a series of concentric arch rings, projecting one in front of the other, were built, giving also an octagonal base; each of these pendentives

7888-517: The arch design: parabola itself, catenary , and weighted catenary . The arches naturally use the inverted (upside-down) versions of these curves. A parabola represents an ideal (all-compression) shape when the load is equally distributed along the span, while the weight of the arch itself is negligible. A catenary is the best solution for the case where an arch with uniform thickness carries just its own weight with no external load. The practical designs for bridges are somewhere in between, and thus use

8024-407: The arch is called " joggled ". A true arch, due to its rise, resolves the vertical loads into horizontal and vertical reactions at the ends, a so called arch action . The vertical load produces a positive bending moment in the arch, while the inward-directed horizontal reaction from the spandrel/abutment provides a counterbalancing negative moment. As a result, the bending moment in any segment of

8160-402: The arch is much smaller than in a beam with the equivalent load and span. The diagram on the right shows the difference between a loaded arch and a beam. Elements of the arch are mostly subject to compression (A), while in the beam a bending moment is present, with compression at the top and tension at the bottom (B). In the past, when arches were made of masonry pieces, the horizontal forces at

8296-404: The arch was built in horizontal courses, up to about one-third of the height, and the rings above were inclined back at a slight angle, so that the bricks of each ring, laid flatwise, adhered till the ring was completed, no centering of any kind being required; the vault thus formed was elliptic in section, arising from the method of its construction. A similar system of construction was employed for

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8432-581: The arch will cause vertical movements at the peak pin joint but will have no appreciable effect on the bases," which further simplifies foundational design. The arch became popular in the Roman times and mostly spread alongside the European influence, although it was known and occasionally used much earlier. Many ancient architectures avoided the use of arches, including the Viking and Hindu ones. True arches, as opposed to corbel arches , were known by

8568-503: The arches themselves got lighter, but the horizontal thrust can be further relieved by a tie connecting the ends of an arch. When evaluated from the perspective of an amount of material required to support a given load, the best solid structures are compression-only; with the flexible materials, the same is true for tension-only designs. There is a fundamental symmetry in nature between solid compression-only and flexible tension-only arrangements, noticed by Robert Hooke in 1676: "As hangs

8704-535: The arches using segments of a circle is due to simplicity of layout and construction, not their structural properties. Consequently, the architects historically used a variety of other curves in their designs: elliptical curves , hyperbolic cosine curves (including catenary ), and parabolic curves . There are two reasons behind the selection of these curves: The hyperbolic curve is not easy to trace, but there are known cases of its use. The non- circumferential curves look similar, and match at shallow profiles, so

8840-472: The bays into square compartments. In the 12th century the first attempts were made to vault over the naves, which were twice the width of the aisles, so it became necessary to include two bays of the aisles to form one rectangular bay in the nave (although this is often mistaken as square). It followed that every alternate pier served no purpose, so far as the support of the nave vault was concerned, and this would seem to have suggested an alternative to provide

8976-761: The best examples provided by the Wells Cathedral . Strainer arches can be " inverted " (upside-down) while remaining structural. When used across railway cuttings to prevent collapse of the walls, strainer arches may be referred to as flying arches . A counter-arch is built adjacent to another arch to oppose its horizontal action or help to stabilize it, for example, when constructing a flying buttress . The large variety of arch shapes (left) can mostly be classified into three broad categories: rounded , pointed , and parabolic . "Round" semicircular arches were commonly used for ancient arches that were constructed of heavy masonry, and were relied heavily on by

9112-459: The cathedral of Soissons (1205) a quadripartite or four-celled vault was introduced, the width of each bay being half the span of the nave, and corresponding therefore with the aisle piers. To this there are some exceptions, in Sant' Ambrogio, Milan, and San Michele, Pavia (the original vault), and in the cathedrals of Speyer , Mainz and Worms , where the quadripartite vaults are nearly square,

9248-478: The central dome of the Jumma Musjid at Bijapur (A.D. 1559), and the other is Gol Gumbaz , the tomb of Muhammad Adil Shah II (1626–1660) in the same town. The vault of the latter was constructed over a hall 135 feet (41 m) square, to carry a hemispherical dome. The ribs, instead of being carried across the angles only, thus giving an octagonal base for the dome, are carried across to the further pier of

9384-603: The centuries. Examples of the ornamental use of lintels are in the hypostyle halls and slab stelas in ancient Egypt and the Indian rock-cut architecture of Buddhist temples in caves. Preceding prehistoric and subsequent Indian Buddhist temples were wooden buildings with structural load-bearing wood lintels across openings. The rock-cut excavated cave temples were more durable, and the non-load-bearing carved stone lintels allowed creative ornamental uses of classical Buddhist elements. Highly skilled artisans were able to simulate

9520-410: The choir aisles of the abbey of Saint-Denis, near Paris , built by the abbot Suger in 1135. It was in the church at Vezelay (1140) that it was extended to the square bay of the porch . As has been pointed out, the aisles had already in the early Christian churches been covered over with groined vaults, the only advance made in the later developments being the introduction of transverse ribs' dividing

9656-421: The concrete had set, not only made the concrete as solid as the rock itself, but to a certain extent neutralized the thrust of the vaults, which formed shells equivalent to that of a metal lid; the Romans, however, do not seem to have recognized the value of this pozzolana mixture, for they otherwise provided amply for the counteracting of any thrust which might exist by the erection of cross walls and buttresses. In

9792-403: The concrete. The rings relieved the centering from the weight imposed, and the two layers of bricks carried the concrete till it had set. As the walls carrying these vaults were also built in concrete with occasional bond courses of brick, the whole structure was homogeneous. One of the important ingredients of the mortar was a volcanic deposit found near Rome, known as pozzolana , which, when

9928-406: The construction of vaults reverted to the geometrical surfaces of the Romans, without, however, always that economy in centering to which they had attached so much importance, and more especially in small structures. In large vaults, where it constituted an important expense, the chief boast of some of the most eminent architects has been that centering was dispensed with, as in the case of the dome of

10064-524: The corbel arch was used already in the Egyptian and Mycenaean architecture in the 3rd and 2nd millennium BC . Like a corbel arch, the triangular arch is not a true arch in a structural sense. Its intrados is formed by two slabs leaning against each other. Brick builders would call triangular any arch with straight inclined sides. The design was common in Anglo-Saxon England until

10200-438: The courses dipped towards the former, and at the apex of the vault were cut to fit one another. In the early English Gothic period, in consequence of the great span of the vault and the very slight rise or curvature of the web, it was thought better to simplify the construction of the web by introducing intermediate ribs between the wall rib and the diagonal rib and between the diagonal and the transverse ribs; and in order to meet

10336-626: The curvatures of the diagonal ribs, producing a straight tunnel running from east to west. Reference has been made to the rib vault in Roman work, where the intersecting barrel vaults were not of the same diameter. Their construction must at all times have been somewhat difficult, but where the barrel vaulting was carried round over the choir aisle and was intersected (as in St Bartholomew-the-Great in Smithfield, London ) by semicones instead of cylinders, it became worse and

10472-400: The curves that represent a compromise that combines both the catenary and the funicular curve for particular non-uniform distribution of load. The practical free-standing arches are stronger and thus heavier at the bottom, so a weighted catenary curve is utilized for them. The same curve also fits well an application where a bridge consists of an arch with a roadway of packed dirt above it, as

10608-713: The development of art and architecture in the South Indian Kannadiga culture. It is remembered today primarily for its Hindu temples ' mandapa , lintels, and other architectural elements, such as at the Chennakesava Temple . The Maya civilization in the Americas was known for its sophisticated art and monumental architecture. The Mayan city of Yaxchilan , on the Usumacinta River in present-day southern Mexico, specialized in

10744-401: The difficulty, however, of working the ribs separately led to two other important changes: (1) the lower part of the transverse diagonal and wall ribs were all worked out of one stone; and (2) the lower horizontal, constituting what is known as the tas-de-charge or solid springer . The tas-de-charge, or solid springer, had two advantages: (1) it enabled the stone courses to run straight through

10880-574: The earliest known examples of any form of vaulting is to be found in the neolithic village of Khirokitia on Cyprus . Dating from c.  6000 BCE , the circular buildings supported beehive shaped corbel domed vaults of unfired mud-bricks and also represent the first evidence for settlements with an upper floor. Similar beehive tombs , called tholoi , exist in Crete and Northern Iraq . Their construction differs from that at Khirokitia in that most appear partially buried and make provision for

11016-405: The eastern end, a similar apse at the western end, and great arches on either side, the walls under which would be pierced with windows. Unlike the Pantheon dome, the upper portions of which are made of concrete, Byzantine domes were made of brick, which were lighter and thinner, but more vulnerable to the forces exerted onto them. The diagram shows the outlines of the solution of the problem. If

11152-417: The employment of centerings of one curve for all the ribs, instead of having separate centerings for the transverse, diagonal wall and intermediate ribs; it was facilitated also by the introduction of the four-centred arch, because the lower portion of the arch formed part of the fan, or conoid, and the upper part could be extended at pleasure with a greater radius across the vault. These ribs were often cut from

11288-425: The ends of an arch caused the need for heavy abutments (cf. Roman triumphal arch ). The other way to counteract the forces, and thus allow thinner supports, was to use the counter-arches , as in an arcade arrangement, where the horizontal thrust of each arch is counterbalanced by its neighbors, and only the end arches need to buttressed . With new construction materials (steel, concrete, engineered wood ), not only

11424-628: The facade of the St Mark's Basilica , the arch became a fixture of the English Decorated style , French Flamboyant , Venetian , and other Late Gothic styles. Ogee arch is also known as reversed curve arch , occasionally also called an inverted arch . The top of an ogee arch sometimes projects beyond the wall, forming the so-called nodding ogee popular in 14th century England ( pulpitum in Southwell Minster ). Each arc of

11560-405: The fixed arch. The three-hinged arch is not only hinged at its base, like the two-hinged arch, yet also at its apex. The additional apical connection allows the three-hinged arch to move in two opposite directions and compensate for any expansion and contraction. This kind of arch is thus not subject to additional stress from thermal change. Unlike the other two kinds of arch, the three-hinged arch

11696-622: The flexible line, so but inverted will stand the rigid arch", thus the study (and terminology) of arch shapes is inextricably linked to the study of hanging chains, the corresponding curves or polygons are called funicular . Just like the shape of a hanging chain will vary depending on the weights attached to it, the shape of an ideal (compression-only) arch will depend on the distribution of the load. There are multiple ways to classify an arch: A sequence of arches can be grouped together forming an arcade . Romans perfected this form, as shown, for example, by arched structures of Pont du Gard . In

11832-407: The following elements: A (left or right) half-segment of an arch is called an arc , the overall line of an arch is arcature (this term is also used for an arcade ). Archivolt is the exposed (front-facing) part of the arch, sometimes decorated (occasionally also used to designate the intrados). If the sides of voussoir blocks are not straight, but include angles and curves for interlocking,

11968-404: The four arches rest. Having obtained a circle for the base of the dome, it is not necessary that the upper portion of the dome should spring from the same level as the arches, or that its domical surface should be a continuation of that of the pendentive. The first and second dome of the Hagia Sophia apparently fell down, so that Justinian determined to raise it, possibly to give greater lightness to

12104-596: The great advance in the science of vaulting shown in this church owed something to the eastern tradition of dome vaulting seen in the Assyrian domes, which are known to us only by the representations in the bas-relief from Nimrud, because in the great water cisterns in Istanbul, known as the Basilica Cistern and Bin bir direk (cistern with a thousand and one columns), we find the intersecting groin vaults of

12240-523: The great dimensions of the vault, it was found necessary to introduce transverse ribs, which were required to give greater strength. Similar transverse ribs are found in Henry VII 's chapel and in the Divinity School at Oxford , where a new development presented itself. One of the defects of the fan vault at Gloucester is the appearance it gives of being half sunk in the wall; to remedy this, in

12376-399: The groins more complicated. This would seem to have led to a change of system and to the introduction of a new feature, which completely revolutionized the construction of the vault. Hitherto the intersecting features were geometrical surfaces, of which the diagonal groins were the intersections, elliptical in form, generally weak in construction and often twisting. The medieval builder reversed

12512-474: The horizontal hydrostatic pressure load. Arches are normally used as supports for many types of vaults , with the barrel vault in particular being a continuous arch. Extensive use of arches and vaults characterizes an arcuated construction , as opposed to the trabeated system, where, like in the architectures of ancient Greece, China, and Japan (as well as the modern steel-framed technique), posts and beams dominate. Arches had several advantages over

12648-600: The inner is structural. Baltasar Neumann , in his baroque churches, perfected light-weight plaster vaults supported by wooden frames. These vaults, which exerted no lateral pressures, were perfectly suited for elaborate ceiling frescoes. In St Paul's Cathedral in London there is a highly complex system of vaults and faux-vaults. The dome that one sees from the outside is not a vault, but a relatively light-weight wooden-framed structure resting on an invisible – and for its age highly original – catenary vault of brick, below which

12784-567: The interior of hall churches , arcades of separating arches were used to separate the nave of a church from the side aisle, or two adjacent side aisles. Two-tiered arches , with two arches superimposed, were sometimes used in Islamic architecture , mostly for decorative purposes. An opening of the arch can be filled, creating a blind arch . Blind arches are frequently decorative, and were extensively used in Early Christian , Romanesque , and Islamic architecture. Alternatively,

12920-402: The intermediate piers of the aisles being of much smaller dimensions. In England sexpartite vaults exist at Canterbury (1175) (set out by William of Sens ), Rochester (1200), Lincoln (1215), Durham (east transept ), and St. Faith's chapel , Westminster Abbey . In the earlier stage of rib vaulting, the arched ribs consisted of independent or separate voussoirs down to the springing;

13056-411: The introduction of the pointed arch for the transverse and wall ribs – the pointed arch had long been known and employed, on account of its much greater strength and of the less thrust it exerted on the walls. When employed for the ribs of a vault, however narrow the span might be, by adopting a pointed arch, its summit could be made to range in height with the diagonal rib; and, moreover, when utilized for

13192-439: The late 11th century ( St Mary Goslany ). Mayan corbel arches are sometimes called triangular due to their shape. Few transformations can be applied to arch shapes. If one impost is much higher than another, the arch (frequently pointed ) is known as ramping arch  [ fr ] , raking arch , or rampant arch (from French : arc rampant ). Originally used to support inclined structures, like staircases , in

13328-617: The late 12th and early 13th centuries ( Salisbury Cathedral ). If the centers are closer to another, the result is a wider blunt arch . The intrados of the cusped arch (also known as multifoil arch , polyfoil arch , polylobed arch , and scalloped arch ) includes several independent circle segments in a scalloped arrangement. These primarily decorative arches are common in Islamic architecture and Northern European Late Gothic, can be found in Romanesque architecture . A similar trefoil arch includes only three segments and sometimes has

13464-579: The late vaulting of the entrance gateways to the colleges. Fan vaulting is peculiar to England, the only example approaching it in France being the pendant of the Lady-chapel at Caudebec-en-Caux , in Normandy. In France, Germany, and Spain the multiplication of ribs in the 15th century led to decorative vaults of various kinds, but with some singular modifications. Thus, in Germany, recognizing that

13600-519: The later Parthian Empire (247 BC–AD 224). This architectural tradition was continued by the Sasanian Empire (224–651), which built the Taq Kasra at Ctesiphon in the 6th century AD, the largest free-standing vault until modern times. An early European example of a voussoir arch appears in the 4th century BC Greek Rhodes Footbridge . Proto-true arches can also be found under

13736-576: The level of the transverse arches and of the wall ribs, and thus gave the appearance of a dome to the vault, such as may be seen in the nave of Sant'Ambrogio, Florence . To meet this, at first the transverse and wall ribs were stilted, or the upper part of their arches was raised, as in the Abbaye-aux-Hommes at Caen , and the Abbey of Lessay , in Normandy . The problem was ultimately solved by

13872-456: The lintel. The lintel is a structural element that is usually rested on stone pillars or stacked stone columns, over a portal or entranceway. A lintel may support the chimney above a fireplace, or span the distance of a path or road, forming a stone lintel bridge. The use of the lintel form as a decorative building element over portals, with no structural function, has been employed in the architectural traditions and styles of most cultures over

14008-547: The look of wood, imitating the nuances of a wooden structure and the wood grain in excavating cave temples from monolithic rock. In freestanding Indian building examples, the Hoysala architecture tradition between the 11th and 14th centuries produced many elaborately carved non-structural stone lintels in the Southern Deccan Plateau region of southern India. The Hoysala Empire era was an important period in

14144-511: The main ribs, and were employed chiefly as decorative features, as, for instance, in the Liebfrauenkirche (1482) of Mühlacker , Germany. One of the best examples of Lierne ribs exists in the vault of the oriel window of Crosby Hall, London . The tendency to increase the number of ribs led to singular results in some cases, as in the choir of Gloucester Cathedral , where the ordinary diagonal ribs become mere ornamental mouldings on

14280-552: The maze cross section. Arch An arch is a curved vertical structure spanning an open space underneath it. Arches may support the load above them, or they may perform a purely decorative role. As a decorative element, the arch dates back to the 4th millennium BC , but structural load-bearing arches became popular only after their adoption by the Ancient Romans in the 4th century BC . Arch-like structures can be horizontal, like an arch dam that withstands

14416-403: The octagon and consequently intersect one another, reducing the central opening to 97 feet (30 m) in diameter, and, by the weight of the masonry they carry, serving as counterpoise to the thrust of the dome, which is set back so as to leave a passage about 12 feet (3.7 m) wide round the interior. The internal diameter of the dome is 124 feet (38 m), its height 175 feet (53 m) and

14552-427: The only change being the occasional substitution of the pointed barrel vault, adopted not only on account of its exerting a less thrust, but because, as pointed out by Fergusson (vol. ii. p. 46), the roofing tiles were laid directly on the vault and a less amount of filling in at the top was required. The continuous thrust of the barrel vault in these cases was met either by semicircular or pointed barrel vaults on

14688-411: The opening can be filled with smaller arches, producing a containing arch , common in Gothic and Romanesque architecture. Multiple arches can be superimposed with an offset, creating an interlaced series of usually (with some exceptions) blind and decorative arches. Most likely of Islamic origin, the interlaced arcades were popular in Romanesque and Gothic architecture. Rear-arch (also rere-arch )

14824-443: The pointed arch rib took place at Cefalù Cathedral and pre-dated the abbey of Saint-Denis . Whilst the pointed rib-arch is often seen as an identifier for Gothic architecture, Cefalù is a Romanesque cathedral whose masons experimented with the possibility of Gothic rib-arches before it was widely adopted by western church architecture. Besides Cefalù Cathedral, the introduction of the pointed arch rib would seem to have taken place in

14960-420: The process, and set up the diagonal ribs first, which were utilized as permanent centres, and on these he carried his vault or web, which henceforward took its shape from the ribs. Instead of the elliptical curve which was given by the intersection of two semicircular barrel vaults, or cylinders, he employed the semicircular arch for the diagonal ribs; this, however, raised the centre of the square bay vaulted above

15096-417: The ratio of the rise fixed at 1 ⁄ 2 of the span, but was applied to the pointed arches, too. The skew arch (also known as an oblique arch ) is used when the arch needs to turn in the horizontal plane, for example, when a bridge crosses the river at an angle different than 90°. A splayed arch is used for the case of unequal spans on the sides of the arch (when, for example, an interior opening in

15232-594: The reign of king Sennacherib they were used to construct aqueducts, such as those at Jerwan . In the provincial city Dūr-Katlimmu they were used to created vaulted platforms. The tradition of their erection, however, would seem to have been handed down to their successors in Mesopotamia , viz. to the Sassanians , who in their palaces in Sarvestan and Firouzabad built domes of similar form to those shown in

15368-488: The rib was no longer a necessary constructive feature, they cut it off abruptly, leaving a stump only; in France, on the other hand, they gave still more importance to the rib, by making it of greater depth, piercing it with tracery and hanging pendants from it, and the web became a horizontal stone paving laid on the top of these decorated vertical webs. This is the characteristic of the great Renaissance work in France and Spain; but it soon gave way to Italian influence, when

15504-442: The ribs of the annular vault , as in the aisle round the apsidal termination of the choir, it was not necessary that the half ribs on the outer side should be in the same plane as those of the inner side; for when the opposite ribs met in the centre of the annular vault, the thrust was equally transmitted from one to the other, and being already a broken arch the change of its direction was not noticeable. The first introduction of

15640-425: The ribs struck from four centres have their springing 57 feet (17 m) from the floor of the hall. The Jumma Musjid dome was of smaller dimensions, on a square of 70 feet (21 m) with a diameter of 57 feet (17 m), and was carried on piers only instead of immensely thick walls as in the tomb; but any thrust which might exist was counteracted by its transmission across aisles to the outer wall. The Muqarnas

15776-398: The same height, or they formed smaller intersections in the lower part of the vault; in both of these cases, however, the intersections or groins were twisted, for which it was very difficult to form a centering, and, moreover, they were of disagreeable effect: though every attempt was made to mask this in the decoration of the vault by panels and reliefs modelled in stucco . A rib vault

15912-477: The same stones as the webs, with the entire vault being treated as a single jointed surface covered in interlocking tracery. The earliest example is perhaps the east walk of the cloister at Gloucester , with its surface consisting of intricately decorated panels of stonework forming conical structures that rise from the springers of the vault. In later examples, as in King's College Chapel , Cambridge, on account of

16048-469: The shorter longitudinal arches. The curvatures of these bounding arches were apparently used as the basis for the web centrings , which was created in the form of two intersecting tunnels as though each web was an arch projected horizontally in three dimensions. The earliest example is thought to be over a small hall at Pergamum , in Asia Minor , but its first employment over halls of great dimensions

16184-485: The stairs of the temple of Apollo at Didyma and the stadium at Olympia . . The ancient Romans learned the semicircular arch from the Etruscans (both cultures apparently adopted the design in the 4th century BC ), refined it and were the first builders in Europe to tap its full potential for above ground buildings: The Romans were the first builders in Europe, perhaps the first in the world, to fully appreciate

16320-476: The stone carving of ornamental lintel elements within structural stone lintels. The earliest carved lintels were created in 723 CE. At the Yaxchilan archaeological site there are fifty-eight lintels with decorative pieces spanning the doorways of major structures. Among the finest Mayan carving to be excavated are three temple door lintels that feature narrative scenes of a queen celebrating the king's anointing by

16456-437: The structure, but mainly in order to obtain increased light for the interior of the church. This was effected by piercing it with forty windows – the effect of which, as the light streaming through these windows, gave the dome the appearance of being suspended in the air. The pendentive which carried the dome rested on four great arches, the thrust of those crossing the church being counteracted by immense buttresses which traversed

16592-399: The surface of an intersected pointed barrel vault, and again in the cloisters, where the introduction of the fan vault , forming a concave-sided conoid , returned to the principles of the Roman geometrical vault. This is further shown in the construction of these fan vaults, for although in the earliest examples each of the ribs above the tas-de-charge was an independent feature, eventually it

16728-404: The thrust of these intermediate ribs a ridge rib was required, and the prolongation of this rib to the wall rib hid the junction of the web at the summit, which was not always very sightly, and constituted the ridge rib. In France, on the other hand, the web courses were always laid horizontally, and they are therefore of unequal height, increasing towards the diagonal rib. Each course also was given

16864-454: The topmost voussoir, the keystone , is positioned, the vault is not self-supporting. Where timber is easily obtained, this temporary support is provided by centering consisting of a framed truss with a semicircular or segmental head, which supports the voussoirs until the ring of the whole arch is completed. Corbelled vaults, also called false vaults, with horizontally joined layers of stone have been documented since prehistoric times; in

17000-615: The traditional image of a roof took precedence over the vault. The separation between interior and exterior – and between structure and image – was to be developed very purposefully in the Renaissance and beyond, especially once the dome became reinstated in the Western tradition as a key element in church design. Michelangelo 's dome for St. Peter's Basilica in Rome, as redesigned between 1585 and 1590 by Giacomo della Porta , for example, consists of two domes of which, however, only

17136-517: The two buildings just quoted, the complete conoid is detached and treated as a pendant . The vault of the Basilica of Maxentius , completed by Constantine, was the last great work carried out in Rome before its fall, and two centuries pass before the next important development is found in the Church of the Holy Wisdom (Hagia Sophia) at Constantinople . It is probable that the realization of

17272-491: The use of centering. Examples have been found in archaeological excavations in Mesopotamia dating to the 2nd and 3rd millennium BCE, which were set in gypsum mortar . A barrel vault is the simplest form of a vault and resembles a barrel or tunnel cut lengthwise in half. The effect is that of a structure composed of continuous semicircular or pointed sections. The earliest known examples of barrel vaults were built by

17408-484: The vault from the inside was the same that one saw from the outside), the European architects of the Middle Ages protected their vaults with wooden roofs. In other words, one will not see a Gothic vault from the outside. The reasons for this development are hypothetical, but the fact that the roofed basilica form preceded the era when vaults begin to be made is certainly to be taken into consideration. In other words,

17544-434: The vault over the great hall at Ctesiphon , where the material employed was fired bricks or tiles of great dimensions, cemented with mortar; but the span was close upon 83 feet (25 m), and the thickness of the vault was nearly 5 feet (1.5 m) at the top, there being four rings of brickwork . Assyrian palaces used pitched-brick vaults, made with sun-dried mudbricks, for gates, subterranean graves and drains. During

17680-463: The wall is larger than the exterior one), the intrados of a round splayed arch is not cylindrical, but has a conical shape. A wide arch with its rise less than 1 ⁄ 2 of the span (and thus the geometric circle of at least one segment is below the springing line) is called a surbased arch (sometimes also a depressed arch ). A drop arch is either a basket handle arch or a blunt arch. The practical arch bridges are built either as

17816-411: The wall, so as to bond the whole together much better; and (2) it lessened the span of the vault, which then required a centering of smaller dimensions. As soon as the ribs were completed, the web or stone shell of the vault was laid on them. In some English work each course of stone was of uniform height from one side to the other; but, as the diagonal rib was longer than either the transverse or wall rib,

17952-455: Was a tendency to increase their number, so that in the nave of Exeter Cathedral three intermediate ribs were provided between the wall rib and the diagonal rib. In order to mask the junction of the various ribs, their intersections were ornamented with richly carved bosses, and this practice increased on the introduction of another short rib, known as the lierne, a term in France given to the ridge rib. Lierne ribs are short ribs crossing between

18088-499: Was a tendency to raise the centres of these vaults, which became slightly domical; in all these cases centering was employed. One good example of the fan vault is that over the staircase leading to the hall of Christ Church, Oxford , where the complete conoid is displayed in its centre carried on a central column. This vault, not built until 1640, is an example of traditional workmanship, probably in Oxford transmitted in consequence of

18224-479: Was found easier to carve them and the web out of the solid stone, so that the rib and web were purely decorative and had no constructional or independent functions. This form of vaulting is found in English late Gothic in which the vault is constructed as a single surface of dressed stones, with the resulting conoid forming an ornamental network of blind tracery. The fan vault would seem to have owed its origin to

18360-411: Was rarely required for the building of the web, a template (Fr. cerce ) being employed to support the stones of each ring until it was complete. In Italy, Germany and Spain the French method of building the web was adopted, with horizontal courses and a domical form. Sometimes, in the case of comparatively narrow compartments, and more especially in clerestories , the wall rib was stilted, and this caused

18496-432: Was reached in Hagia Sophia, for although it formed the model on which all subsequent Byzantine churches were based, so far as their plan was concerned, no domes approaching the former in dimensions were even attempted. The principal difference in some later examples is that which took place in the form of the pendentive on which the dome was carried. Instead of the spherical spandril of Hagia Sophia, large niches were formed in

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