Types of abutment

The selection of appropriate abutments for a bridge should be made at the same stage as the choice of the deck superstructure. There are many types of abutment in use in the United Kingdom. A comprehensive survey by the Building Research Establishment (Hambly, 1979) revealed a wide variation in the basic assumptions made in the design of these structures which is still valid today.

Solid or full-height abutments (Figure 2a) are common, but are often not favoured on the basis of aesthetics, and can tend to restrict the line of sight of traffic on slip roads. In addition, they can produce a tunnel-like appearance on wide structures. Skeletal abutments and mass concrete bankseats are commonly employed where open side-spans are required (Figures 2b and 3). The bankseat is more suited to the top of a cutting slope where simple footings can be used just below existing ground level. However, it can also be applied to the embankment situation where pile supports driven through the fill may be necessary (Figure 3). The cost of piling will influence the relative economy of this choice of end support.

In the embankment case, a skeletal abutment founded close to the previous existing ground level can be more economic, but there are complications in the construction of this type of structure. The contractor is faced with a severe restriction on backfilling operations, and casting of

Solid abutments

Deck

Solid abutments

Deck

Abutment Engineering

Piers

Figure 1 Abutments and piers

Piers

Figure 1 Abutments and piers the transverse capping beam causes further delay to the construction sequence. The magnitude and distribution of the earth pressures acting on the buried columns are particularly in doubt and there is limited experimental evidence available to form the basis of a realistic theoretical analysis.

Despite the reservations expressed above, a solid wall abutment design (Figures 4 and 5) is often favoured in practice because it produces a minimum overall length for the superstructure. An open side span solution produces a

Spread footing or pile cap

Bridge deck

Bridge deck

Spread footing or pile cap

Abutment Capping Beam
(a) Retaining wall abutment

Bridge deck bearing

Cross-beam

Columns

Spread footing

Bridge deck

Bridge deck bearing

Bridge deck

Cross-beam

Columns

Spread footing

Spill Thru Abutments

(b) Spill-through or skeleton abutment

Figure 2 (a) Solid and (b) skeletal or 'spill-through' abutment (Clayton et a/., 1993)

(b) Spill-through or skeleton abutment

Figure 2 (a) Solid and (b) skeletal or 'spill-through' abutment (Clayton et a/., 1993)

Picture Spill Through AbutmentWhat Does Bankseat Abutment Look Like
Figure 3 Bridge deck supported by piers and bankseats

more attractive appearance and can be used to assist with farm access or provide additional areas for flood relief in a river crossing. In the case of bankseat and skeletal abutment forms of construction, the savings arising from lower material content in the abutments and the smaller amounts of granular backfill have to be off-set against the cost of the additional deck area required.

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Responses

  • ellena vasquez
    Where is the bearing in a beam bridge?
    6 years ago
  • senait
    What does a bankseat abutment look like?
    6 years ago
  • johan
    What is a bridge skeleton abutment?
    5 years ago
  • tom
    What is use abutment with figures?
    3 years ago
  • belisarius
    What is types of abutments?
    2 years ago
  • Richard Harvey
    What is abutment in bridge construction?
    2 years ago
  • What is spill through abutment?
    1 year ago
  • marcho
    How many type of abutment bridge?
    1 year ago
  • Leah
    What is mean by abutment and its figure?
    1 year ago
  • lena
    What is open abutment?
    10 months ago
  • gebre
    What is an open bridge abutment?
    6 months ago

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