{{Short description|Part of a structure that provides stiffness and strength}} {{about|a notion of structural engineering|an architectural element|Vertical support}} A '''structural support''' is a part of a building or structure that provides the necessary stiffness and strength in order to resist the internal forces (vertical forces of gravity and lateral forces due to wind and earthquakes) and guide them safely to the ground. External loads (actions of other bodies) that act on buildings cause internal forces (forces and couples by the rest of the structure) in building support structures. Supports can be either at the end or at any intermediate point along a structural member or a constituent part of a building and they are referred to as connections, joints or restraints.<ref name=structure>{{cite book |date=2012 |title=Structure for Architects: A Primer |location=Canada |publisher=John Wileys and Sons |author=Ashwani Bedi and Ramsey Dabby }}</ref>
Building support structures, no matter what materials are used, have to give accurate and safe results. A structure depends less on the weight and stiffness of a material and more on its geometry for stability.<ref name=Francis>{{cite book |last1=Ching |first1=Francis D.K |last2=Onouye |first2=Barry |last3=Zuberbuhler |first3=Douglas |date=2009 |title=Building Structures Illustrated: Patterns, Systems and Design |url=https://archive.org/details/buildingstructur0000chin |url-access=registration |location=Hoboken, New Jersey |publisher=John Wiley & Sons }}</ref> Whatever the condition is, a specific rigidity is necessary for connection designs. The support connection type has effects on the load bearing capacity of each element, which makes up a structural system. Each support condition influences the behaviour of the elements and therefore, the system. Structures can be either Horizontal-span support systems (floor and roof structures) or Vertical building structure systems (walls, frames, cores, etc.)<ref name=wolfgang>{{cite web |url=https://www.slideshare.net/WolfgangSchueller/building-structures-as-architecture-wolfgang-schueller |title=Building Structures as Architecture |last=Schueller |first=Wolfgang |date=25 August 2015 |website=SlideShare |publisher=LinkedIn Corporation |access-date=18 September 2018 }}</ref>
==Structure==
Structure is necessary for buildings but architecture, as an idea, does not require structure. Every building has both load-bearing structures and non-load bearing portions. Structural members form systems and transfer the loads that are acting upon the structural systems, through a series of elements to the ground. Building Structure Elements include Line (beams, columns, cables, frames or arches, space frames, surface elements (walls, slab or shells) and Freeform.<ref name=wolfgang></ref>
The structure's functional requirements will narrow the possible forms that one can consider. Other factors such as the availability of materials, foundation conditions, the aesthetic requirements and economic limitations also play important roles in establishing the structural form. <ref name=West>{{cite book |last=West |first=Harry H. |date=1993 |title=Fundamentals of Structural Analysis |publisher=John Wilsey & Sons, Inc. }}</ref> Structural systems or all their members and parts are considered to be in equilibrium if the systems are initially at rest and remain at rest when a system of forces and couples acts on them.<ref name=UK></ref> They are not aspects of a model that should be guessed. To be able to analyze a structure, it is necessary to be clear about the forces that can be quite complicated.
There are two types of forces, External Forces which are the actions of other bodies on the structure under consideration and Internal Forces which the rest of the structure exert on a member or portion of the structure as forces and couples.<ref name=chris>{{cite web |url=http://web.mit.edu/4.441/1_lectures/1_lecture13/1_lecture13.html |title=Support and Connection Types |author=Chris H. Luebkeman and Donald Peting |date=1998 |website=MIT (Massachusetts Institute of Technology) |publisher=Google Custom Search |access-date=18 September 2018 }}</ref> A little deflection or play is required for a structure to protect other surrounding materials from those forces.
==Support structure== {{cleanup|section|reason=contradictory and incomplete definitions of types of support|date=July 2019}}
There are five basic idealized support structure types, categorized by the types of deflection they constrain: '''roller''', '''pinned''', '''fixed''', '''hanger''' and '''simple support'''.<ref name=structure></ref>
===Roller supports===
A roller support allows thermal expansion and contraction of the span and prevents damage on other structural members such as a pinned support. The typical application of roller supports is in large bridges. In civil engineering, roller supports can be seen at one end of a bridge.
A roller support cannot prevent translational movements in horizontal or lateral directions and any rotational movement but prevents vertical translations.<ref name=structure></ref><ref name=UK>{{cite web |url=http://www.engr.uky.edu/~gebland/CE%20382/CE%20382%20PDF%20Lecture%20Slides/CE%20382%20L4%20-%20Support%20Reactions.pdf |title=Statics of Structural Supports |author=<!--Not stated--> |website=University of Kentucky College of Engineering |access-date=16 October 2018 }}</ref> Its reaction force is a single linear force perpendicular to, and away from, the surface (upward or downward). This support type is assumed to be capable of resisting normal displacement.
It can be rubber bearings, rocker or a set of gears allowing a limited amount of lateral movement. A structure on roller skates, for example, remains in place as long as it must only support itself. As soon as lateral load pushes on the structure, a structure on roller skates will roll away in response to the force.<gallery> File:Roller Bearing, Jensen Drive (Hill Street) Bridge over Buffalo Bayou, Houston, Texas 1310261116 (10577360794).jpg|Roller supports under a bridge File:Prince Alfred Bridge - Gundagai Detail of the roller mounting carrying the top chord.jpg|Rollers carrying the top chord of a bridge File:Kingsgate Bridge - detail of expansion joint on deck balustrade.jpg|Expansion joint on a bridge </gallery>
===Pinned support===
A pinned support or hinge support attaches the only web of a beam to a girder called a shear connection. The support can exert a force on a member acting in any direction and prevent translational movements, or relative displacement of the member-ends in all directions but cannot prevent any rotational movements.<ref name=structure></ref> Its reaction forces are single linear forces of unknown direction or horizontal and vertical forces which are components of the single force of unknown direction.<ref name=UK></ref>
A pinned support is just like a human elbow. It can be extended and flexed (rotation), but you cannot move your forearm left to right (translation). One benefit of pinned supports is not having internal moment forces and only their axial force playing a big role in designing them. However, a single pinned support cannot completely restrain a structure. At least two supports are needed to resist the moment.<ref name=Noman></ref> Applying in trusses is one frequent way we can use this support. <gallery> File:Sydney Harbour Bridge hinge.jpg|Hinge on a bridge File:Billerbeck, Lange Straße, Türscharnier -- 2020 -- 0271.jpg|Hinge on a door File:Box, watch (AM 673042-9).jpg|Hinge on a box File:Close-up view of a pin-connected joint where eye-bar and built-up members are connected with a single pin. HAER ALA,36-BRIPO.V,1-8.tif </gallery>
===Fixed support===
Rigid or fixed supports maintain the angular relationship between the joined elements and provide both force and moment resistance. It exerts forces acting in any direction and prevents all translational movements (horizontal and vertical) as well as all rotational movements of a member. These supports’ reaction forces are horizontal and vertical components of a linear resultant; a moment.<ref name=UK></ref> It is a rigid type of support or connection. The application of the fixed support is beneficial when we can only use single support, and people most widely used this type as the only support for a cantilever.<ref name=Noman>{{cite web |url=https://www.slideshare.net/NomanBindresh/support-typesnotes-member-civil-architectural-structure?qid=a315e106-c7eb-427a-8fca-fc85c218d260&v=&b=&from_search=1 |title=Support types-notes member (civil, architectural structure) |author=<!--Not stated--> |date=2 February 2017 |website=SlideShare |publisher=LinkedIn Corporation |access-date=22 October 2018 }}</ref> They are common in beam-to-column connections of moment-resisting steel frames and beam, column and slab connections in concrete frames.<gallery> File:Sujikai.jpg|Cross bracing File:Fixing bolts on a wind turbine foundation - geograph.org.uk - 1240451.jpg|Column base attachment point File:Straßenbrunnen77 Kladow Imchenplatz (5).jpg </gallery>
===Hanger support===
A hanger support only exerts a force and prevents a member from acting or translating away in the direction of the hanger. However, this support cannot prevent translational movement in all directions and any rotational movement.<ref name=structure></ref><ref name=UK></ref> This is one of the simplest structural forms in which the elements are in pure tension. Structures of this type range from simple guyed or stayed structures to large cable-supported bridge and roof systems.<ref name="West" /><gallery> File:Kleiderbügel Wald- und Golfhotel Lottental, Bochum, Germany 2013 (Alter Fritz) 04.JPG File:Infinity bridge cable connectors-2.jpg File:Whittier Bridge Hanger Cables Support Whittier Bridge Arch (17983188194).jpg </gallery>
===Simple support===
A simple support is basically where the structural member rests on an external structure as in two concrete blocks holding a resting plank of wood on their tops. This support is similar to roller support in a sense that restrains vertical forces but not horizontal forces. Therefore, it is not widely used in real life structures unless the engineer can be sure that the member will not translate.<ref name="Noman" /><gallery> File:Stone bench in the cemetery at Bro Church 3.jpg|Simple support of a stone bench File:Plank bridge over drainage ditch - geograph.org.uk - 1790460.jpg|Simple bridge over a ditch File:Stonehenge Winter 2010.jpg|Stonehenge </gallery>
===Varieties of support=== {| class = "wikitable" |+ Varieties of support<ref>{{Cite book |author = Tatsurō Sakimoto |year = 1991 |title = Kōzō rikigaku. 001. |trans-title=Structural Dynamics 001 |series = Kiso doboku kōgaku shirīzu |publisher = Morikitashuppan |pages = 36–40 |isbn = 4-627-42510-4 |language = ja }}</ref> ! rowspan="2" | Name ! rowspan="2" | Schematic diagram ! rowspan="2" | Simple figure ! colspan="3" | Allowed movement ! colspan="2" | Reaction |- ! Vertical ! Horizontal ! Rotation (Moment) ! Direction ! Number |- | rowspan="2" | Roller or simple (movable) support | rowspan="2" | 150px|center | 150px|center | rowspan="2" {{no}} | rowspan="2" {{yes}} | rowspan="2" {{yes}} | rowspan="2" | 150px|center | rowspan="2" | 1 |- | 150px|center |- | Pinned or hinged support | 150px|center | 150px|center | {{no}} | {{no}} | {{yes}} | 150px|center | 2 |- | Middle hinge (for axial member) | 150px|center | 150px|center | {{no}} | {{no}} | {{yes}} | | 2 |- | Fixed support | 150px|center | 150px|center | {{no}} | {{no}} | {{no}} | 150px|center | 3 |- | Middle hinge (for beam member) | 150px|center | | {{no}} | {{yes}} | {{no}} | | 2 |}
== See also == * Bracket (architecture), structural or decorative element that projects from a surface, usually to carry weight or strengthen an angle * Joining technology, methods of assembly of engineering structures by mechanical joint of two or more elements
==References== {{reflist}}
Nl:Oplegging Category:Civil engineering