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A column or pillar in architecture and structural engineering is a structural element that transmits, through compression , the weight of the structure above to other structural elements below. In other words, a column is a compression member . The term column applies especially to a large round support (the shaft of the column) with a capital and a base or pedestal , which is made of stone, or appearing to be so. A small wooden or metal support is typically called a post . Supports with a rectangular or other non-round section are usually called piers .

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105-473: For the purpose of wind or earthquake engineering , columns may be designed to resist lateral forces. Other compression members are often termed "columns" because of the similar stress conditions. Columns are frequently used to support beams or arches on which the upper parts of walls or ceilings rest. In architecture, "column" refers to such a structural element that also has certain proportional and decorative features. These beautiful columns are available in

210-567: A volute , an ornament shaped like a scroll , at the four corners. The height-to-thickness ratio is around 9:1. Due to the more refined proportions and scroll capitals, the Ionic column is sometimes associated with academic buildings. Ionic style columns were used on the second level of the Colosseum. The Corinthian order is named for the Greek city-state of Corinth , to which it was connected in

315-403: A boundary-layer wind tunnel , or more recently, use of computational fluid dynamics techniques has increased. The pedestrian level wind speeds for a given exceedance probability are calculated to allow for regional wind speeds statistics. The vertical wind profile used in these studies varies according to the terrain in the vicinity of the buildings (which may differ by wind direction), and

420-544: A broad selection of styles and designs in round tapered, round straight, or square shaft styles. A column might also be a decorative element not needed for structural purposes; many columns are engaged , that is to say form part of a wall. A long sequence of columns joined by an entablature is known as a colonnade . All significant Iron Age civilizations of the Near East and Mediterranean made some use of columns. In ancient Egyptian architecture as early as 2600 BC,

525-428: A column is reached is called the critical or buckling load. The state of instability is reached when a slight increase of the column load causes uncontrollably growing lateral deflections leading to complete collapse. For an axially loaded straight column with any end support conditions, the equation of static equilibrium, in the form of a differential equation, can be solved for the deflected shape and critical load of

630-552: A combination of a cylinder and a slab. The structures of Armenian palaces, churches, courtyards ( Dvin , Aruch , Zvartnots , Ishkhan , Banak, Haghpat , Sanahin , Ani structures) are diverse and unique. In the Renaissance period the feature became of the greatest importance and its variety almost as great as in the Romanesque and Gothic styles. The flat pilaster, which was employed extensively in this period, called for

735-475: A concrete foundation, a steel column must have a base plate to spread the load over a larger area, and thereby reduce the bearing pressure. The base plate is a thick, rectangular steel plate usually welded to the bottom end of the column. The Roman author Vitruvius , relying on the writings (now lost) of Greek authors, tells us that the ancient Greeks believed that their Doric order developed from techniques for building in wood. The earlier smoothed tree-trunk

840-427: A cross section that lacks symmetry may suffer torsional buckling (sudden twisting) before, or in combination with, lateral buckling. The presence of the twisting deformations renders both theoretical analyses and practical designs rather complex. Eccentricity of the load, or imperfections such as initial crookedness, decreases column strength. If the axial load on the column is not concentric, that is, its line of action

945-465: A hard and fast set of canonical rules for the execution of capitals. Two further, specifically Roman orders of architecture have their characteristic capitals, the sturdy and primitive Tuscan capitals , typically used in military buildings, similar to Greek Doric, but with fewer small moldings in its profile, and the invented Composite capitals not even mentioned by Vitruvius, which combined Ionic volutes and Corinthian acanthus capitals, in an order that

1050-518: A more elongated form, and sometimes being combined with scrolls, generally within the context of Buddhist stupas and temples . Indo-Corinthian capitals also incorporated figures of the Buddha or Bodhisattvas , usually as central figures surrounded by, and often under the shade of, the luxurious foliage of Corinthian designs. Byzantine capitals vary widely, mostly developing from the classical Corinthian, but tending to have an even surface level, with

1155-482: A planar rendition of the capital, executed in high relief. This affected the designs of capitals. A traditional 15th-century variant of the Composite capital turns the volutes inwards above stiffened leaf carving. In new Renaissance combinations in capital designs most of the ornament can be traced to Classical Roman sources. The 'Renaissance' was as much a reinterpretation as a revival of Classical norms. For example,

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1260-708: A rare octagonal tomb. Chisholm, Hugh, ed. (1911). "Engaged Column". Encyclopædia Britannica. 9 (11th ed.). Cambridge University Press. pp. 404–405. Stierlin, Henri The Roman Empire: From the Etruscans to the Decline of the Roman Empire, TASCHEN, 2002 Alderman, Liz (7 July 2014). "Acropolis Maidens Glow Anew". The New York Times. Retrieved 9 July 2014. Stokstad, Marilyn; Cothren, Michael (2014). Art History (Volume 1 ed.). New Jersey: Pearson Education, Inc. p. 110. Wind engineering Wind engineering

1365-451: A sharp point where the fillets are located on Ionic and Corinthian order columns. Most classical columns arise from a basis, or base, that rests on the stylobate , or foundation , except for those of the Doric order , which usually rest directly on the stylobate. The basis may consist of several elements, beginning with a wide, square slab known as a plinth . The simplest bases consist of

1470-428: A single piece of stone. Monolithic columns are among the heaviest stones used in architecture. Other stone columns are created out of multiple sections of stone, mortared or dry-fit together. In many classical sites, sectioned columns were carved with a centre hole or depression so that they could be pegged together, using stone or metal pins. The design of most classical columns incorporates entasis (the inclusion of

1575-456: A single, prominent pillar or column, often made of stone. A number of world cultures incorporated pillars into tomb structures. In the ancient Greek colony of Lycia in Anatolia , one of these edifices is located at the tomb of Xanthos . In the town of Hannassa in southern Somalia , ruins of houses with archways and courtyards have also been found along with other pillar tombs, including

1680-408: A slight outward curve in the sides) plus a reduction in diameter along the height of the column, so that the top is as little as 83% of the bottom diameter. This reduction mimics the parallax effects which the eye expects to see, and tends to make columns look taller and straighter than they are while entasis adds to that effect. There are flutes and fillets that run up the shaft of columns. The flute

1785-452: A small scale, as they are easy to produce in wood by turning on a lathe (hence also the style's popularity for spindles on furniture and stairs). A Caryatid is a sculpted female figure serving as an architectural support taking the place of a column or a pillar supporting an entablature on her head. The Greek term karyatides literally means "maidens of Karyai ", an ancient town of Peloponnese . In architecture, an engaged column

1890-410: A strong wind with a very long return period, such as 50 years or more. The design wind speed is determined from historical records using extreme value theory to predict future extreme wind speeds. Wind speeds are generally calculated based on some regional design standard or standards. The design standards for building wind loads include: The advent of high-rise tower blocks led to concerns regarding

1995-582: Is De architectura by the 1st-century BC Roman architect Vitruvius , who discussed the different proportions of each of these orders and made recommendations for how the column capitals of each order were to be constructed and in what proportions. In the Roman world and within the Roman Empire , the Tuscan order was employed, originally from Italy and with a capital similar to Greek Doric capitals, while

2100-481: Is a column embedded in a wall and partly projecting from the surface of the wall, sometimes defined as semi or three-quarter detached. Engaged columns are rarely found in classical Greek architecture, and then only in exceptional cases, but in Roman architecture they exist in abundance, most commonly embedded in the cella walls of pseudoperipteral buildings. Pillar tombs are monumental graves, which typically feature

2205-474: Is a subset of mechanical engineering , structural engineering , meteorology , and applied physics that analyzes the effects of wind in the natural and the built environment and studies the possible damage, inconvenience or benefits which may result from wind. In the field of engineering it includes strong winds, which may cause discomfort, as well as extreme winds, such as in a tornado , hurricane or heavy storm , which may cause widespread destruction. In

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2310-486: Is also a simple design, the base and capital both being series of cylindrical disks of alternating diameter. The shaft is almost never fluted. The proportions vary, but are generally similar to Doric columns. Height to width ratio is about 7:1. The Ionic column is considerably more complex than the Doric or Tuscan. It usually has a base and the shaft is often fluted (it has grooves carved up its length). The capital features

2415-507: Is at the top and bottom with a delicate uniting curve. The sloping side of the echinus becomes flatter in the later examples, and in the Colosseum at Rome forms a quarter round (see Doric order ). In versions where the frieze and other elements are simpler the same form of capital is described as being in the Tuscan order . Doric reached its peak in the mid-5th century BC, and was one of

2520-470: Is equal to or more than 400 mm. Massive columns have the ability to increase in carrying strength over long time periods (even during periods of heavy load). Taking into account the fact, that possible structural loads may increase over time as well (and also the threat of progressive failure), massive columns have an advantage compared to non-massive ones. When a column is too long to be built or transported in one piece, it has to be extended or spliced at

2625-479: Is equal to the square root of (I/A), K = ratio of the longest half sine wave to the actual column length, E t = tangent modulus at the stress F cr , and KL = effective length (length of an equivalent hinged-hinged column). From Equation (2) it can be noted that the buckling strength of a column is inversely proportional to the square of its length. When the critical stress, F cr ( F cr = P cr / A , where A  = cross-sectional area of

2730-412: Is essential for their analysis and design. Again, wind load is a dominant load in the analysis and design of all long-span cable bridges . ⚫ Capital (architecture) In architecture , the capital (from Latin caput  'head') or chapiter forms the topmost member of a column (or a pilaster ). It mediates between the column and the load thrusting down upon it, broadening

2835-441: Is from four to six times as tall as its diameter; it has twenty broad flutes; the capital consists simply of a banded necking swelling out into a smooth echinus, which carries a flat square abacus; the Doric entablature is also the heaviest, being about one-fourth the height column. The Greek Doric order was not used after c. 100 B.C. until its “rediscovery” in the mid-eighteenth century. The Tuscan order , also known as Roman Doric,

2940-412: Is not precisely coincident with the centroidal axis of the column, the column is characterized as eccentrically loaded. The eccentricity of the load, or an initial curvature, subjects the column to immediate bending. The increased stresses due to the combined axial-plus-flexural stresses result in a reduced load-carrying ability. Column elements are considered to be massive if their smallest side dimension

3045-400: Is often approximated using a power law: where: The knowledge of wind engineering is used to analyze and design all high-rise buildings, cable- suspension bridges and cable-stayed bridges , electricity transmission towers and telecommunication towers and all other types of towers and chimneys. The wind load is the dominant load in the analysis of many tall buildings, so wind engineering

3150-594: Is often grouped in categories, such as: Wind turbines are affected by wind shear. Vertical wind-speed profiles result in different wind speeds at the blades nearest to the ground level compared to those at the top of blade travel, and this, in turn, affects the turbine operation. The wind gradient can create a large bending moment in the shaft of a two bladed turbine when the blades are vertical. The reduced wind gradient over water means shorter and less expensive wind turbine towers can be used in shallow seas. For wind turbine engineering , wind speed variation with height

3255-458: Is represented in the bottom level of the Colosseum and the Parthenon , and was therefore considered to be able to hold more weight. The height-to-thickness ratio is about 8:1. The shaft of a Doric Column is almost always fluted . The Greek Doric, developed in the western Dorian region of Greece, is the heaviest and most massive of the orders. It rises from the stylobate without any base; it

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3360-556: Is the part of the column that is indented in with a semi circular shape. The fillet of the column is the part between each of the flutes on the Ionic order columns. The flute width changes on all tapered columns as it goes up the shaft and stays the same on all non tapered columns. This was done to the columns to add visual interest to them. The Ionic and the Corinthian are the only orders that have fillets and flutes. The Doric style has flutes but not fillets. Doric flutes are connected at

3465-487: The Achaemenid Persian capital , the brackets are carved with two heavily decorated back-to-back animals projecting right and left to support the architrave ; on their backs they carry other brackets at right angles to support the cross timbers. The bull is the most common, but there are also lions and griffins . The capital extends below for further than in most other styles, with decoration drawn from

3570-496: The Great Hypostyle Hall of Karnak ( c.  1224 BC ), where 134 columns are lined up in sixteen rows, with some columns reaching heights of 24 metres. One of the most important type are the papyriform columns. The origin of these columns goes back to the 5th Dynasty . They are composed of lotus (papyrus) stems which are drawn together into a bundle decorated with bands: the capital, instead of opening out into

3675-520: The Ionic . Composite capitals line the principal space of the nave. Ionic capitals are used behind them in the side spaces, in a mirror position relative to the Corinthian or composite orders (as was their fate well into the 19th century, when buildings were designed for the first time with a monumental Ionic order). At Hagia Sophia, though, these are not the standard imperial statements. The capitals are filled with foliage in all sorts of variations. In some,

3780-523: The Roman imperial period saw the emergence of the Composite order , with a hybrid capital developed from Ionic and Corinthian elements. The Tuscan and Corinthian columns were counted among the classical canon of orders by the architects of Renaissance architecture and Neoclassical architecture . The Doric capital is the simplest of the five Classical orders : it consists of the abacus above an ovolo molding, with an astragal collar set below. It

3885-670: The Sunga Empire period. Some capitals with strong Greek and Persian influence have been found in northeastern India in the Maurya Empire palace of Pataliputra , dating to the 4th–3rd century BC. Examples such as the Pataliputra capital belong to the Ionic order rather than the later Corinthian order . They are witness to relations between India and the West from that early time. Indo-Corinthian capitals correspond to

3990-419: The architectural order . The treatment of its detail may be an indication of the building's date. Capitals occur in many styles of architecture, before and after the classical architecture in which they are so prominent. The two earliest Egyptian capitals of importance are those based on the lotus and papyrus plants respectively, and these, with the palm tree capital, were the chief types employed by

4095-507: The classical tradition are based. The Composite order was formalized in the 16th century following Roman Imperial examples such as the Arch of Titus in Rome. It adds Ionic volutes to Corinthian acanthus leaves. From the highly visible position it occupies in all colonnaded monumental buildings, the capital is often selected for ornamentation; and is often the clearest indicator of

4200-548: The dosseret required to carry the arch , the springing of which was much wider than the abacus of the capital. On eastern capitals the eagle, the lion and the lamb are occasionally carved, but treated conventionally. There are two types of capitals used at Hagia Sophia : Composite and Ionic. The composite capital that emerged during the Late Byzantine Empire , mainly in Rome, combines the Corinthian with

4305-573: The kingdoms of Israel and Judah starting from the 9th century BCE, as well as in Moab , Ammon , and at Cypriot sites such as the city-state of Tamassos in the Archaic period. The orders, structural systems for organising component parts, played a crucial role in the Greeks' search for perfection of ratio and proportion. The Greeks and Romans distinguished three classical orders of architecture,

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4410-607: The lotus . Some of the most popular types of capitals were the Hathor , lotus, papyrus and Egyptian composite. Most of the types are based on vegetal motifs. Capitals of some columns were painted in bright colors. Some kind of volute capital is shown in the Assyrian bas-reliefs , but no Assyrian capital has ever been found; the enriched bases exhibited in the British Museum were initially misinterpreted as capitals. In

4515-409: The 3rd century BC. The top is made of a band of rosettes , eleven in total for the fronts and four for the sides. Below that is a band of bead and reel pattern, then under it a band of waves, generally right-to-left, except for the back where they are left-to-right. Further below is a band of egg-and-dart pattern, with eleven "tongues" or "eggs" on the front, and only seven on the back. Below appears

4620-406: The 4th-7th centuries the capitals of Armenian architectural facades and masonry facades are tall rectangular stones with a total volume, which are converted into a slab by means of a bell. In the structures of the early period ( Ereruyk , Tekor , Tsopk , etc.) they were sculpted with plant and animal images, palm trees. In the 10th century and in the following centuries, capitals are mainly formed by

4725-464: The Alan Davenport wind-loading chain or in short "wind-loading chain" that describes how different components contribute to the final load calculated on the structure. The design of buildings must account for wind loads, and these are affected by wind shear . For engineering purposes, a power law wind-speed profile may be defined as: where: Typically, buildings are designed to resist

4830-598: The Ancient Greeks, followed by the Romans, loved to use them on the outside as well, and the extensive use of columns on the interior and exterior of buildings is one of the most characteristic features of classical architecture, in buildings like the Parthenon . The Greeks developed the classical orders of architecture, which are most easily distinguished by the form of the column and its various elements. Their Doric , Ionic , and Corinthian orders were expanded by

4935-491: The Composite order volutes are larger, however, and there is generally some ornament placed centrally between the volutes. Despite this origin, very many Composite capitals in fact treat the two volutes as different elements, each springing from one side of their leafy base. In this, and in having a separate ornament between them, they resemble the Archaic Greek Aeolic order , though this seems not to have been

5040-693: The Doric, Ionic, and Corinthian orders; each had different types of capitals atop the columns of their hypostyle and trabeate monumental buildings. Throughout the Mediterranean Basin , the Near East , and the wider Hellenistic world including the Greco-Bactrian Kingdom and the Indo-Greek Kingdom , numerous variations on these and other designs of capitals co-existed with the regular classical orders. The only architectural treatise of classical antiquity to survive

5145-535: The Egyptians, until under the Ptolemies in the 3rd to 1st centuries BC, various other river plants were also employed, and the conventional lotus capital went through various modifications. Many motifs of Egyptian ornamentation are symbolic , such as the scarab , or sacred beetle, the solar disk , and the vulture . Other common motifs include palm leaves, the papyrus plant, and the buds and flowers of

5250-489: The Etruscans and are found on their tombs. Although the Romans perceived it as especially Italianate, the Tuscan capital found on Roman monuments is in fact closer to the Greek Doric order than to Etruscan examples, its capital being nearby identical with the Doric. The Romans invented the Composite order by uniting the Corinthian order with the Ionic capital, possibly as early as Augustus 's reign. In many versions

5355-581: The Romans to include the Tuscan and Composite orders. Some of the most elaborate columns in the ancient world were those of the Persians , especially the massive stone columns erected in Persepolis . They included double-bull structures in their capitals . The Hall of Hundred Columns at Persepolis, measuring 70 × 70 metres, was built by the Achaemenid king Darius I (524–486 BC). Many of

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5460-970: The Senate Vestibule in the United States Capitol in 1807, he introduced six columns that he "Americanized" with ears of corn (maize) substituting for the European acanthus leaves. As Latrobe reported to Thomas Jefferson in August ;1809, Another example is the Delhi Order invented by the British architect Edwin Lutyens for New Delhi 's central palace, Viceroy's House, now the Presidential residence Rashtrapati Bhavan , using elements of Indian architecture . Here

5565-457: The Tholos of Epidaurus (400 BC) illustrate the transition between the earlier Greek capital, as at Bassae , and the Roman version that Renaissance and modern architects inherited and refined (See the more complete discussion at Corinthian order ). In Roman architectural practice , capitals are briefly treated in their proper context among the detailing proper to each of the " Orders ", in

5670-459: The ancient Persian columns are standing, some being more than 30 metres tall. Tall columns with bull's head capitals were used for porticoes and to support the roofs of the hypostylehall, partly inspired by the ancient Egyptian precedent. Since the columns carried timber beams rather than stone, they could be taller, slimmer and more widely spaced than Egyptian ones. Columns, or at least large structural exterior ones, became much less significant in

5775-463: The architect Imhotep made use of stone columns whose surface was carved to reflect the organic form of bundled reeds, like papyrus , lotus and palm . In later Egyptian architecture faceted cylinders were also common. Their form is thought to derive from archaic reed-built shrines. Carved from stone, the columns were highly decorated with carved and painted hieroglyphs , texts, ritual imagery and natural motifs. Egyptian columns are famously present in

5880-459: The architecture of the Middle Ages . The classical forms were abandoned in both Byzantine and Romanesque architecture in favour of more flexible forms, with capitals often using various types of foliage decoration, and in the West scenes with figures carved in relief . During the Romanesque period, builders continued to reuse and imitate ancient Roman columns wherever possible; where new,

5985-583: The area around Paris. The most varied were carved in 1130–1170. In Britain and France the figures introduced into the capitals are sometimes full of character, these are referred to as historiated (or figured capital). These capitals, however, are not equal to those of the Early English Gothic , in which foliage is treated as if copied from metalwork, and is of infinite variety, being found in small village churches as well as in cathedrals. Armenian capitals are often versions of Byzantine forms. In

6090-416: The area of the column's supporting surface. The capital, projecting on each side as it rises to support the abacus , joins the usually square abacus and the usually circular shaft of the column. The capital may be convex, as in the Doric order ; concave, as in the inverted bell of the Corinthian order ; or scrolling out, as in the Ionic order . These form the three principal types on which all capitals in

6195-517: The budget allowed, carvers were able to indulge their inventiveness. Capitals were sometimes used to hold depictions of figures and narrative scenes, especially in the Romanesque . In Romanesque architecture and Gothic architecture capitals throughout western Europe present as much variety as in the East, and for the same reason, that the sculptor evolved his design in accordance with the block he

6300-466: The bull and elephant; a lion occupies the other place. The wheel "Ashoka Chakra" from its base has been placed onto the centre of the National Flag of India The Pataliputra capital is a monumental rectangular capital with volutes designs, that was discovered in the palace ruins of the ancient Mauryan Empire capital city of Pataliputra (modern Patna , northeastern India ). It is dated to

6405-423: The column returns to its straight form when the lateral force is removed. If the column load is gradually increased, a condition is reached in which the straight form of equilibrium becomes so-called neutral equilibrium, and a small lateral force will produce a deflection that does not disappear and the column remains in this slightly bent form when the lateral force is removed. The load at which neutral equilibrium of

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6510-415: The column), is greater than the proportional limit of the material, the column is experiencing inelastic buckling. Since at this stress the slope of the material's stress-strain curve, E t (called the tangent modulus ), is smaller than that below the proportional limit, the critical load at inelastic buckling is reduced. More complex formulas and procedures apply for such cases, but in its simplest form

6615-582: The column. With hinged, fixed or free end support conditions the deflected shape in neutral equilibrium of an initially straight column with uniform cross section throughout its length always follows a partial or composite sinusoidal curve shape, and the critical load is given by f c r ≡ π 2 E I m i n L 2 ( 1 ) {\displaystyle f_{cr}\equiv {\frac {\pi ^{2}{\textit {E}}I_{min}}{{L}^{2}}}\qquad (1)} where E = elastic modulus of

6720-432: The construction site. A reinforced concrete column is extended by having the steel reinforcing bars protrude a few inches or feet above the top of the concrete, then placing the next level of reinforcing bars to overlap, and pouring the concrete of the next level. A steel column is extended by welding or bolting splice plates on the flanges and webs or walls of the columns to provide a few inches or feet of load transfer from

6825-434: The critical buckling load formula is given as Equation (3), f c r ≡ F y − F y 2 4 π 2 E ( K L r 2 ) ( 3 ) {\displaystyle f_{cr}\equiv {F_{y}}-{\frac {F_{y}^{2}}{4\pi ^{2}E}}\left({\frac {KL}{r^{2}}}\right)\qquad (3)} A column with

6930-663: The emperor's and the Buddha's words. The capital today serves as the emblem of the Republic of India . Minus the inverted bell -shaped lotus flower, this has been adopted as the National Emblem of India , seen from another angle, showing the horse on the left and the bull on the right of the Ashoka Chakra in the circular base on which the four Indian lions are standing back to back. On the side shown here there are

7035-430: The emphasis was on elegance and beauty, as illustrated by twisted columns. Often they were decorated with mosaics. Renaissance architecture was keen to revive the classical vocabulary and styles, and the informed use and variation of the classical orders remained fundamental to the training of architects throughout Baroque , Rococo and Neo-classical architecture . Early columns were constructed of stone, some out of

7140-589: The entire context, as in Greek Revival . There are numerous newly invented orders, sometimes called nonce orders , where a different ornamentation of the capital is typically a key feature. Within the bounds of decorum , a certain amount of inventive play has always been acceptable within the classical tradition. These became increasingly common after the Renaissance. When Benjamin Latrobe redesigned

7245-456: The famous lion-gate of Mycenae where two lions stand each side of a column. Being made of wood these early columns have not survived, but their stone bases have and through these we may see their use and arrangement in these palace buildings. The Egyptians, Persians and other civilizations mostly used columns for the practical purpose of holding up the roof inside a building, preferring outside walls to be decorated with reliefs or painting, but

7350-842: The fields of wind energy and air pollution it also includes low and moderate winds as these are relevant to electricity production and dispersion of contaminants. Wind engineering draws upon meteorology , fluid dynamics , mechanics , geographic information systems , and a number of specialist engineering disciplines, including aerodynamics and structural dynamics . The tools used include atmospheric models , atmospheric boundary layer wind tunnels , and computational fluid dynamics models. Wind engineering involves, among other topics: Wind engineering may be considered by structural engineers to be closely related to earthquake engineering and explosion protection . Some sports stadiums such as Candlestick Park and Arthur Ashe Stadium are known for their strong, sometimes swirly winds, which affect

7455-462: The frontal end of a wall, such as the front of the side wall of a temple. The top of an anta is often highly decorated, usually with bands of floral motifs. The designs often respond to an order of columns, but usually with a different set of design principles. In order not to protrude excessively from the wall surface, these structures tend to have a rather flat surface, forming brick-shaped capitals, called "anta capitals". Anta capitals are known from

7560-429: The least weight, and also has the slenderest ratio of thickness to height. Height to width ratio is about 10:1. The Composite order draws its name from the capital being a composite of the Ionic and Corinthian capitals. The acanthus of the Corinthian column already has a scroll-like element, so the distinction is sometimes subtle. Generally the Composite is similar to the Corinthian in proportion and employment, often in

7665-479: The main motif, a flame palmette , growing among pebbles. The Sarnath capital is a pillar capital, sometimes also described as a "stone bracket", discovered in the archaeological excavations at the ancient Buddhist site of Sarnath . The pillar displays Ionic volutes and palmettes . It has been variously dated from the 3rd century BCE during the Mauryan Empire period, to the 1st century BCE, during

7770-548: The many cultures that the Persian Empire conquered including Egypt , Babylon , and Lydia . There are double volutes at the top and, inverted, bottom of a long plain fluted section which is square, although the shaft of the column is round, and also fluted. The earliest Aegean capital is that shown in the frescoes at Knossos in Crete (1600 BC); it was of the convex type, probably moulded in stucco . Capitals of

7875-514: The material, I min = the minimal moment of inertia of the cross section, and L = actual length of the column between its two end supports. A variant of (1) is given by f c r ≡ π 2 E T ( K L r ) 2 ( 2 ) {\displaystyle f_{cr}\equiv {\frac {\pi ^{2}E_{T}}{({\frac {KL}{r}})^{2}}}\qquad (2)} where r = radius of gyration of column cross-section which

7980-455: The mid-5th century BC. The style prevailed in Ionian lands, centred on the coast of Asia Minor and Aegean islands . The order's form was far less set than the Doric, with local variations persisting for many decades. In the Ionic capitals of the archaic Temple of Artemis at Ephesus (560 BC) the width of the abacus is twice that of its depth, consequently the earliest Ionic capital known

8085-438: The most famous Minoan palace of Knossos . The Minoans employed columns to create large open-plan spaces, light-wells and as a focal point for religious rituals. These traditions were continued by the later Mycenaean civilization , particularly in the megaron or hall at the heart of their palaces. The importance of columns and their reference to palaces and therefore authority is evidenced in their use in heraldic motifs such as

8190-462: The much more abundant Corinthian-style capitals crowning columns or pilasters, which can be found in the northwestern Indian subcontinent , particularly in Gandhara , and usually combine Hellenistic and Indian elements. These capitals are typically dated to the first century BC, and constitute important elements of Greco-Buddhist art . The Classical design was often adapted, usually taking

8295-510: The only complete architectural textbook to have survived from classical times, the De architectura , by Marcus Vitruvius Pollio, better known as Vitruvius , dedicated to the emperor Augustus . The various orders are discussed in Vitruvius' books iii and iv. Vitruvius describes Roman practice in a practical fashion. He gives some tales about the invention of each of the orders, but he does not give

8400-462: The orders accepted by the Romans. Its characteristics are masculinity, strength and solidity. The Doric capital consists of a cushion-like convex moulding known as an echinus, and a square slab termed an abacus. In the Ionic capital , spirally coiled volutes are inserted between the abacus and the ovolo. This order appears to have been developed contemporaneously with the Doric, though it did not come into common usage and take its final shape until

8505-834: The ornamentation undercut with drills. The block of stone was left rough as it came from the quarry, and the sculptor evolved new designs to his own fancy, so that one rarely meets with many repetitions of the same design. One of the most remarkable designs features leaves carved as if blown by the wind; the finest example being at the 8th-century Hagia Sophia (Thessaloniki) . Those in the Cathedral of Saint Mark, Venice  (1071) specially attracted John Ruskin 's fancy. Others appear in Sant'Apollinare in Classe , Ravenna  (549). The capital in San Vitale, Ravenna  (547) shows above it

8610-454: The period. However, according to the architectural historian Vitruvius , the column was created by the sculptor Callimachus , probably an Athenian , who drew acanthus leaves growing around a votive basket. In fact, the oldest known Corinthian capital was found in Bassae , dated at 427 BC. It is sometimes called the feminine order because it is on the top level of the Colosseum and holding up

8715-642: The playing conditions. Wind engineering as a separate discipline can be traced to the UK in the 1960s, when informal meetings were held at the National Physical Laboratory , the Building Research Establishment, and elsewhere. The term "wind engineering" was first coined in 1970. Alan Garnett Davenport was one of the most prominent contributors to the development of wind engineering. He is well known for developing

8820-454: The plinth alone, sometimes separated from the column by a convex circular cushion known as a torus . More elaborate bases include two toruses, separated by a concave section or channel known as a scotia or trochilus. Scotiae could also occur in pairs, separated by a convex section called an astragal , or bead, narrower than a torus. Sometimes these sections were accompanied by still narrower convex sections, known as annulets or fillets. At

8925-605: The route of their development in early Imperial Rome . Equally, where the Greek Ionic volute is usually shown from the side as a single unit of unchanged width between the front and back of the column, the Composite volutes are normally treated as four different thinner units, one at each corner of the capital, projecting at some 45° to the façade. The Lion Capital of Ashoka is an iconic capital which consists of four Asiatic lions standing back to back, on an elaborate base that includes other animals. A graphic representation of it

9030-404: The same moldings as the base. In the case of free-standing columns, the decorative elements atop the shaft are known as a finial . Modern columns may be constructed out of steel, poured or precast concrete, or brick, left bare or clad in an architectural covering, or veneer. Used to support an arch, an impost , or pier, is the topmost member of a column. The bottom-most part of the arch, called

9135-666: The scrolls was an abacus, more shallow than that in Doric examples, and again ornamented with egg-and-dart. It has been suggested that the foliage of the Greek Corinthian capital was based on the Acanthus spinosus , that of the Roman on the Acanthus mollis . Not all architectural foliage is as realistic as Isaac Ware's ( illustration, right ) however. The leaves are generally carved in two "ranks" or bands, like one leafy cup set within another. The Corinthian capitals from

9240-617: The second, concave type, include the richly carved examples of the columns flanking the Tomb of Agamemnon in Mycenae (c. 1100 BC): they are carved with a chevron device, and with a concave apophyge on which the buds of some flowers are sculpted. Volute capitals, also known as proto-Aeolic capitals, are encountered in Iron-Age Southern Levant and ancient Cyprus , many of them in royal architectural contexts in

9345-439: The shape of a bellflower , swells out and then narrows again like a flower in bud. The base, which tapers to take the shape of a half-sphere like the stem of the lotus, has a continuously recurring decoration of stipules. The Minoans used whole tree-trunks, usually turned upside down in order to prevent re-growth, stood on a base set in the stylobate (floor base) and topped by a simple round capital. These were then painted as in

9450-536: The small, lush leaves appear to be caught up in the spinning of the scrolls – clearly, a different, nonclassical sensibility has taken over the design. The capitals at Basilica of San Vitale in Ravenna ( Italy ) show wavy and delicate floral patterns similar to decorations found on belt buckles and dagger blades. Their inverted pyramidal form has the look of a basket. Capitals in early Islamic architecture are derived from Graeco-Roman and Byzantine forms, reflecting

9555-436: The springing, rests on the impost. As the axial load on a perfectly straight slender column with elastic material properties is increased in magnitude, this ideal column passes through three states: stable equilibrium, neutral equilibrium, and instability. The straight column under load is in stable equilibrium if a lateral force, applied between the two ends of the column, produces a small lateral deflection which disappears and

9660-423: The time of the Doric order. An anta capital can sometimes be qualified as a "sofa" capital or a "sofa anta capital" when the sides of the capital broaden upward, in a shape reminiscent of a couch or sofa . Anta capitals are sometimes hard to distinguish from pilaster capitals, which are rather decorative, and do not have the same structural role as anta capitals. The origins of the Tuscan order lie with

9765-445: The top of the shaft is a capital , upon which the roof or other architectural elements rest. In the case of Doric columns, the capital usually consists of a round, tapering cushion, or echinus, supporting a square slab, known as an abax or abacus . Ionic capitals feature a pair of volutes , or scrolls, while Corinthian capitals are decorated with reliefs in the form of acanthus leaves. Either type of capital could be accompanied by

9870-418: The training of most of the masons producing them. In both periods small columns are often used close together in groups, often around a pier that is in effect a single larger column, or running along a wall surface. The structural importance of the individual column is thereby greatly reduced. In both periods, though there are common types, the sense of a strict order with rules was not maintained, and when

9975-420: The upper tiers of colonnades . Height to width ratio is about 11:1 or 12:1. A Solomonic column , sometimes called " barley sugar ", begins on a base and ends in a capital, which may be of any order, but the shaft twists in a tight spiral, producing a dramatic, serpentine effect of movement. Solomonic columns were developed in the ancient world, but remained rare there. A famous marble set, probably 2nd century,

10080-439: The upper to the lower column section. A timber column is usually extended by the use of a steel tube or wrapped-around sheet-metal plate bolted onto the two connecting timber sections. A column that carries the load down to a foundation must have means to transfer the load without overstressing the foundation material. Reinforced concrete and masonry columns are generally built directly on top of concrete foundations. When seated on

10185-697: The volutes of ancient Greek and Roman Ionic capitals had lain in the same plane as the architrave above them. This had created an awkward transition at the corner – where, for example, the designer of the temple of Athena Nike on the Acropolis in Athens had brought the outside volute of the end capitals forward at a 45-degree angle. This problem was more satisfactorily solved by the 16th-century architect Sebastiano Serlio , who angled outwards all volutes of his Ionic capitals. Since then use of antique Ionic capitals, instead of Serlio's version, has lent an archaic air to

10290-529: The wind nuisance caused by these buildings to pedestrians in their vicinity. A number of wind comfort and wind danger criteria were developed from 1971, based on different pedestrian activities, such as: Other criteria classified a wind environment as completely unacceptable or dangerous. Building geometries consisting of one and two rectangular buildings have a number of well-known effects: For more complex geometries, pedestrian wind comfort studies are required. These can use an appropriately scaled model in

10395-458: Was adopted as the official Emblem of India in 1950. This powerfully carved lion capital from Sarnath stood a top a pillar bearing the edicts of the emperor Ashoka . Like most of Ashoka's capitals, it is brilliantly polished. Located at the site of Buddha's first sermon and the formation of the Buddhist order, it carried imperial and Buddhist symbols, reflecting the universal authority of both

10500-717: Was brought to Old St. Peter's Basilica by Constantine I , and placed round the saint's shrine, and was thus familiar throughout the Middle Ages, by which time they were thought to have been removed from the Temple of Jerusalem . The style was used in bronze by Bernini for his spectacular St. Peter's baldachin , actually a ciborium (which displaced Constantine's columns), and thereafter became very popular with Baroque and Rococo church architects, above all in Latin America , where they were very often used, especially on

10605-479: Was carving, but in the west variety goes further, because of the clustering of columns and piers . The earliest type of capital in Lombardy and Germany is known as the cushion-cap, in which the lower portion of the cube block has been cut away to meet the circular shaft. These types were generally painted at first with geometrical designs, afterwards carved. The finest carving comes from France, especially from

10710-455: Was developed in the lands occupied by the Dorians , one of the two principal divisions of the Greek race. It became the preferred style of the Greek mainland and the western colonies (southern Italy and Sicily ). In the Temple of Apollo , Syracuse (c. 700 BC), the echinus moulding has become a more definite form: this in the Parthenon reaches its culmination, where the convexity

10815-482: Was otherwise quite similar in proportions to the Corinthian, itself an order that Romans employed much more often than Greeks. The increasing adoption of Composite capitals signalled a trend towards freer, more inventive (and often more coarsely carved) capitals in Late Antiquity . The anta capital is not a capital which is set on top of column, but rather on top of an anta , a structural post integrated to

10920-399: Was replaced by a stone cylinder. The Doric order is the oldest and simplest of the classical orders. It is composed of a vertical cylinder that is wider at the bottom. It generally has neither a base nor a detailed capital . It is instead often topped with an inverted frustum of a shallow cone or a cylindrical band of carvings. It is often referred to as the masculine order because it

11025-501: Was virtually a bracket capital. A century later, in the temple on the Ilissus , the abacus has become square (See the more complete discussion at Ionic order ). According to the Roman architect Vitruvius , the Ionic order's main characteristics were beauty, femininity, and slenderness, derived from its basis on the proportion of a woman. The volutes of an Ionic capital rest on an echinus, almost invariably carved with egg-and-dart. Above

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