Pillar, in architecture and building construction, any isolated, vertical structural member such as a pier, column, or post. A beam is a structural element that is capable of withstanding load primarily by resisting against bending.
It may be constructed of a single piece of stone or wood or built up of units, such as bricks. It may be any shape in cross section. A pillar commonly has a load-bearing or stabilizing function, but it may also stand alone, as do commemorative pillars.
Pillars may be rectangular, circular, or polygonal in shape; they may taper toward the top or be of uniform diameter. An engaged, attached, or embedded column is one that is built into a wall and protrudes only partially from it; this type of column came to serve a decorative rather than structural purpose in the Roman pilaster. A cluster or compound column is a group of columns connected with each other to form a single unit. A rostral column is a pillar decorated with the prow of a ship, or rostrum, to serve as a naval monument. Modern columns tend to be made of iron, steel, or concrete and are simply designed.
early use of the columns
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 the architect Imhotep made use of stone columns whose surface was carved to reflect the organic form of bundled reeds; in later Egyptian architecture faceted cylinders were also common. Egyptian columns are famously present in the Great Hypostyle Hall of Karnak (ca. 1224 BC), where 134 columns are lined up in 16 rows, with some columns reaching heights of 24 metres.
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 the ancient Persian columns are standing, some being more than 30 metres tall.
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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 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 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 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 the Romans to include the Tuscan and Composite orders .
Columns, or at least large structural exterior ones, became much less significant in the architecture of the Middle Ages. The classical forms were abandoned in both Byzantine architecture and the Romanesque and Gothic architecture or Europe 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. 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.
what are beams?
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In building construction, a beam is a horizontal member spanning an opening and carrying a load that may be a brick or stone wall above the opening, in which case the beam is often called a lintel. The load may be a floor or roof in a building, in which case the beam is called a floor joist or a roof joist. In a bridge deck the lightly loaded longitudinal beams are the stringers; the heavier, transverse members are called floor beams.
Historically beams were squared timbers but are also metal, stone, or combinations of wood and metal such as a flitch beam. Beams generally carry vertical gravitational forces but can also be used to carry horizontal loads (e.g., loads due to an earthquake or wind or in tension to resist rafter thrust as a tie beam or (usually) compression as a collar beam). The loads carried by a beam are transferred to columns, walls, or girders, which then transfer the force to adjacent structural compression members. In light frame construction joists may rest on beams. In carpentry a beam is called a plate as in a sill plate or wall plate, beam as in a summer beam or dragon beam.
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how many types of beam are used in construction?
In engineering, beams are of several types:
- Simply supported – a beam supported on the ends which are free to rotate and have no moment resistance.
- Fixed – a beam supported on both ends and restrained from rotation.
- Over hanging – a simple beam extending beyond its support on one end.
- Double overhanging – a simple beam with both ends extending beyond its supports on both ends.
- Continuous – a beam extending over more than two supports.
- Cantilever – a projecting beam fixed only at one end.
- Trussed – a beam strengthened by adding a cable or rod to form a truss.
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What they have in common and what is different?
– Both, the beams and columns are load carrying elements, but differ in the method or the way of handling the load by each member. That means, the columns bear the compression of the load, whereas beams bear the bending moment and the shear force of the load.
– Similar materials are used in the construction of columns and beams, which are steel, timber and concrete.
– A building can’t stand without columns but a building can stand without beams.
– Design classifications of beams and columns are different. Column are classified as slender or short, while beams are classified as T,L or rectangular.
– The ties of the columns and the ties or shear reinforcement of beams act differently.
– One should be careful in stating the behavior of each, because the behaviors of the two elements are different.