CANTILEVER
| A cantilever is a beam that is supported only on one end. It isn't the strongest structure but is used as a structural element when the designer does not want to see a support under an object. Common uses of the cantilever in buildings are stairs and balconies; these structures are supported by only one end that is very strong. |
This pile of books illustrates how a cantilever works. The vertical force of the books on top of the extended book holds it in place. |
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| Here students demonstrate a human cantilever supporting the weight of the center student. | A balcony construction may have no visible supports as these balconies on 22nd Street in Philadelphia, PA. Some balconies may also have additional triangulation underneath as part of the support structure. |
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| A series of cantilevers are used in this staircase at the Kimmel Center in Philadelphia. For more information and photos of cantilevers and other interesting structures at this new performance space click here. | This bridge in Easton, PA is cantilevered out from the main support structure. |
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| A series of cantilevers are used for this pedestal seating on M.M. Seylar Elementary School's playground. | This seating system at the Doylestown Center shopping complex uses a cantilever system. |
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| This house on Callowhill street in Perkasie has a second floor that cantilevers out over the first floor. | This round roof at the Bucks County Courthouse is cantilevered out from the main support structure. |
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| The overhang on this gas station on Walnut Street in South Perkasie uses cantilever structures supported by two columns. | Many pieces of construction equipment like this bucket lift support weight on an extended pole or beam. This cantilever can move in different positions with the use of a hydraulic lift. |
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The diving boards and lifeguard chairs at Menlo Pool in Perkasie are also examples of cantilever structures. |
CORBELED ARCH
A corbeled arch is not a true arch. It is a series of cantilevers that are staggered inwards and are supported by the weight of the other stones or bricks above it. These have been used forever, and they were used to span an opening. An example of this is an igloo.
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| This illustration of a corbeled arch is created by using a series of books. |
