A load-bearing wall or bearing wall, is one in which a wall of a structure bears the weight and force resting upon it, conducting the vertical load from the upper structure to the foundation. A bearing wall is opposed to a curtain wall, which uses the strength of a sub-wall to bear the weight of the curtain such as the brick facade on a skyscraper, and superstructure, usually a steel frame, to carry the weight of the floors and walls inside the curtain walls protection. The materials most often used to construct load-bearing walls in large buildings are concrete, block, or brick.
Load-bearing walls are one of the earliest forms of construction.
The development of the flying buttress in Gothic architecture allowed structures to maintain an open interior space, transferring more weight to the buttresses instead of to central bearing walls. Notre Dame Cathedral, for example, has a load-bearing wall structure with flying buttresses.
The birth of the skyscraper era, the concurrent rise of steel as a more suitable framing system first designed by William Le Baron Jenney, and the limitations of load-bearing construction in large buildings led to a decline in the use of load-bearing walls in large-scale, commercial structures.
An arch is a structure that spans a space while supporting weight (e.g. a doorway in a stone wall). Arches appeared as early as the 2nd millennium BC in Mesopotamian brick architecture and their systematic use started with the Ancient Romans who were the first to apply the technique to a wide range of structures.
The semicircular arch was followed in Europe by the pointed Gothic arch or ogive whose centreline more closely followed the forces of compression and which was therefore stronger. The semicircular arch can be flattened to make an elliptical arch as in the Ponte Santa Trinita. The parabolic and catenary arches are now known to be the theoretically strongest forms. Parabolic arches were introduced in construction by the Spanish architect Antoni Gaudí, who admired the structural system of Gothic style, but for the buttresses, which he termed “architectural crutches”. The catenary and parabolic arches carry all horizontal thrust to the foundation and so do not need additional elements.
1.Keystone
2.Voussoir
3.Back
4.Impost
5.Intrados
6.Rise
7.Clear span, "Bay"
8.Abutment
A dome is a structural element of architecture that resembles the hollow upper half of a sphere. Dome structures made of various materials have a long architectural lineage extending into prehistory.
A dome can be thought of as an arch which has been rotated around its central vertical axis. Thus domes, like arches, have a great deal of structural strength when properly built and can span large open spaces without interior supports. Corbel domes achieve their shape by extending each circular layer of stones inward slightly farther than the previous, lower, one until they meet at the top. These are sometimes called 'false' domes. 'True', or 'real' domes are formed with increasingly inward-angled layers which have ultimately turned 90 degrees from the base of the dome to the top. Domes have been constructed from a variety of building materials over the centuries: from mud to stone, wood, brick, concrete, metal, glass and plastic.
Post and Lintel:
Post and lintel (or Post and beam) is a simple architrave where a horizontal member (the lintel—or header) is supported by two vertical posts at either end. This form is commonly used to support the weight of the structure located above the openings in a bearing wall created by windows and doors.
A lintel (or header) is a horizontal beam used in the construction of buildings, and is a major architectural contribution of ancient Greece. It usually supports the masonry above a window or door opening. (Also sometimes spelled 'lintol', 'lintil',' lyntil'.)
Lintels may be made of wood, stone, steel or reinforced or pre tensioned concrete.
For example, at Stonehenge, stone lintels top off some of the megaliths. In typical homes today, lintels are commonly used in fireplaces where one will span the opening of the firebox. In this use they are most often steel, either straight for a square opening or arched for a more decorative effect.
Flying buttress:
A flying buttress, or arc-boutant, is a specific type of buttress usually found on religious buildings, not all of which are cathedrals. They are used to transmit the horizontal force of a vaulted ceiling through the walls and across an intervening space (which might be used for an aisle, chapel or cloister), to a counterweight outside the building. As a result, the buttress seemingly flies through the air, and hence is known as a "flying" buttress.
Although they are considered a hallmark of Gothic architecture, they were employed by the Byzantines, and in some Romanesque work, but were generally masked by other constructions or hidden under a roof. However, by 1150 flying buttresses were intentionally left exposed by architects and became decorative features in their own right, such as in the cathedrals of Chartres, Sens, Le Mans, Paris, Beauvais, and Reims.
Its presence outside the clerestory walls created a web of stonework that disguised the solidity of the structure, and gives the impression that the cathedral is being suspended from heaven. It balanced the network of ribs under the interior vaults that give the same impression, as if the upper stonework is forming a tent-like canopy over the congregation. It has been suggested that these external arches created a screen that 'hid' the walls to diminish the impact of weightiness so common in earlier architecture. From the inside the wide windows and the increasingly thin shafts under the vaults continued the feeling that the building was an illusion, that weight had become weightless. Hence the phrase Canopy of Paradise.
This technique has also been used by Canadian architect William P. Anderson to build lighthouses at the beginning of the 20th century.
Written by:
Yusuf Wahbi Adewale
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