Abutment

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This article is about physical structures. For the mathematical concept, see spectral sequence. For property law, see abutter. For dental structures, see abutment (dentistry).
Cream-colored concrete abutment providing vertical support to the red-wine-colored rail bridge, and to the earthen fill of the embankment of the bridge approach. Photograph of the Old Town Railway station in Staten Island, New York City.
This bridge abutment provides vertical support to the bridge on the left and horizontal support to earthen fill embankment of the bridge approach on the right.
These bridge piers formerly supported multiple spans over Ontario's Grand River.

In engineering, abutment refers to the substructure at the end of a bridge span whereon the bridge's superstructure rests. Single-span bridges have abutments at each end which provide vertical and lateral support for the bridge, as well as acting as retaining walls to resist lateral movement of the earthen fill of the bridge approach. Multi-span bridges require piers to support ends of spans unsupported by abutments.[1]

The term may also refer to the structure supporting one side of an arch,[2] or masonry used to resist the lateral forces of a vault.[3] The word derives from the verb "abut", meaning to "touch by means of a mutual border".

Use of abutments in engineering[edit]

An abutment may be used for the following:

  • To transfer loads from a superstructure to its foundation elements.
  • To resist and/or transfer self weight, lateral loads (such as the earth pressure) and wind loads.
  • To support one end of an approach slab.

Types of abutments[edit]

There are different types of abutments including:

  • Gravity Abutment, resists horizontal earth pressure with its own dead weight
  • U Abutment, U shaped gravity abutment
  • Cantilever Abutment, Cantilever retaining wall designed for large vertical loads
  • Full Height Abutment, Cantilever abutment that extends from the underpass grade line to the grade line of the overpass roadway
  • Stub Abutment, Short abutments at the top of an embankment or slope. Usually supported on piles
  • Semi-Stub Abutment, Size between full height and stub abutment
  • Counterfort Abutment, Similar to counterfort retaining walls
  • Spill-through Abutment, Vertical buttresses with open spaces between them
  • MSE systems,“Reinforced earth” system: modular units with metallic reinforcement
  • Pile Bent abutment, Similar to Spill-through Abutment

References[edit]

  1. ^ Abbett, Robert W. (1957). American Civil Engineering Practice III. New York: John Wiley & Sons. pp. 26–22&26–32. 
  2. ^ Beall, Christine (1987). Masonry Design and Detailing for Architects, Engineers and Builders. McGraw-Hill. p. 449. ISBN 0-07-004223-3. 
  3. ^ Pevsner, N. (1970) Cornwall; 2nd ed. Harmondsworth: Penguin; p. 245

External links[edit]