explain the general features of the abutment

Hello Aspirant,

An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end which provide vertical and lateral support for the span, as well as acting as retaining walls to resist lateral movement of the earthen fill of the bridge approach.

Abutments placed at either end of a bridge typically include the following five features:-

• Bridge Seat
• Wing walls
• Backwall
• Pile
• Footing

1. Bridge Seat : This horizontal shelf supports the bridge deck and is near, or on, the top of an abutment. On the embankment, these will hold the end of a span, while those placed along a span will provide support to reduce extended stress.
2. Wing Walls : These are only included in abutments that connect to the embankment. They are short retaining walls to prevent erosion and add stability.
3. Backwall : Also only included in embankment abutments, backwalls rise above the seat to provide a horizontal brace from the bridge deck and reduce erosion at the connecting point.
4. Pile : An abutment's pile can either be a vertical wall connecting the seat with the foot or a row of columns that serve the same purpose. On an embankment, the vertical wall structure provides a retaining wall, while mid-span abutments use more cost-effective columns.
5. Footing : This part of an abutment connects the vertical, load-bearing portion of the abutment to the ground and is usually buried beneath the earth. It consists of a horizontal surface, sometimes wider than the bridge, to distribute the weight.

There are four types of bridge Abutments:-

• Typical gravity Abutment
• U-Abutment
• Spill-Through Abutment
• Pile Bent Abutment

I hope this information will helpful for you.

Feel free to ask any query.

All the best!!