- cantilever
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/kan"tl ee'veuhr, -ev'euhr/, n.1. any rigid structural member projecting from a vertical support, esp. one in which the projection is great in relation to the depth, so that the upper part is in tension and the lower part in compression.2. Building Trades, Civ. Engin. any rigid construction extending horizontally well beyond its vertical support, used as a structural element of a bridge (cantilever bridge), building foundation, etc.3. Aeron. a form of wing construction in which no external bracing is used.4. Archit. a bracket for supporting a balcony, cornice, etc.v.i.5. to project in the manner of a cantilever.v.t.6. to construct in the manner of a cantilever.Also, cantalever, cantaliver.[1660-70; perh. CANT2 + -I- + LEVER]
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Projecting beam or other horizontal member supported at one or more points but not at both ends.Some engineers distinguish between a cantilever, supported at only one fixed end, and an overhanging beam that projects beyond one of its end supports. The free, unsupported end is capable of supporting a weight or surface, such as a concrete slab. Any beam built into a wall with a projecting free end forms a cantilever, which may carry a balcony, canopy, roof, or part of a building above. Cantilevering can be used for constructions as simple as bookshelves or as complicated as bridges.* * *
beam supported at one end and carrying a load at the other end or distributed along the unsupported portion. The upper half of the thickness of such a beam is subjected to tensile stress, tending to elongate the fibres, the lower half to compressive stress, tending to crush them. Cantilevers are employed extensively in building construction and in machines. In building, any beam built into a wall and with the free end projecting forms a cantilever. Longer cantilevers are incorporated in a building when clear space is required below, with the cantilevers carrying a gallery, roof, canopy, runway for an overhead travelling crane, or part of a building above.In bridge building a cantilever construction is employed for large spans in certain sites, especially for heavy loading; the classic type is the Forth Bridge, Scotland, composed of three cantilevers with two connecting suspended spans. Cantilever cranes are necessary when a considerable area has to be served, as in steel stockyards and shipbuilding berths. In the lighter types a central travelling tower sustains the cantilever girders on either side; the big hammerhead cranes (up to 300-ton capacity) used in working on ships that have proceeded from the yards to fitting-out basins have a fixed tower and revolving pivot reaching down to rotate the cantilever in a circle.* * *
Universalium. 2010.
