What Is Bridge?
A bridge is a structure carrying a roadway, pathway, railway, etc. across a river, or other obstacles. A bridge is built so that people or vehicles can cross from one side to the other.
There are different types of bridges depending upon the specific physical and design scope requirements. In this article, we will discuss the components and parts of bridge.
Components Of Bridge
The various parts and components of a bridge are as follows:
- Girder or beam
- Bridge tower
- Pier cap
- Pile cap
- Bridge anchor
- Suspension cable
Let us learn each component of a bridge in detail below.
Deck is the portion that carries all the traffic.
The portion supports the deck slab and girder and connects one sub-structure to the other. That means all the elements of the bridge attached to a supporting system can be categorized as superstructure.
The parts of the bridge which support the superstructure and transmit all the structural loads of the bridge to the foundations. For example, piers, abutments, etc.
Foundation is the portion that transmits loads to the bearing strata. Foundation is required to support the piers, bridge towers, and portal frames. Generally, piles and well foundations such as H-pile, bore piles, pipe piles, or precast concrete piles are adopted.
5. Girder Or Beam
The beam or girder is the part of the superstructure which bends along the span. The deck is supported by beams.
6. Bridge Tower
It is the vertical supporting part used for cable-stayed or suspension bridges. High-strength concrete and Insitu method are adopted to construct the bridge tower.
Pier is the part of the substructure that supports the superstructure and transfers loads of superstructure to the foundations. Pier is suitable for spanned bridges with a maximum width of deck up to 8 m (2 traffic lanes).
The shape and size of the pier mainly depend on aesthetics, site, space, and economic constraints of the construction. Usually, bridge pier is constructed by in situ method with large panel formwork.
8. Pier Cap
Pier cap is the topmost part of a pier that transfers loads from the superstructure to the pier. It is also known as headstock. It provides sufficient seating for the girders and distributes the loads from the bearings to the piers.
Bearing is a device which supports the parts of superstructure and transfers loads and movements from the deck to the substructure and foundation.
The main purpose of providing a bearing is to permit controlled movement and decrease the stress involved.
10. Pile & Pile Cap
Pile is a slender member driven into the surrounding soil to resist the loads. Pile cap is a thick reinforced concrete slab cast on top of the group piles to distribute loads.
11. Bridge Anchor
Bridge anchor is only used in suspension and cable-stayed bridges to resist the pull from suspension cable or counter span of the bridge.
12. Suspension Cable
It is used in suspension and cable-stayed bridges for the hanging, supporting and counter balancing of the bridge deck.