An arch bridge is a bridge that utilizes the shape of an arch to support its load. It has abutments at each end that are shaped as a curved arch.
Arch bridges work by transferring the weight of the bridge and any traffic on it, partially into a horizontal thrust that is restrained by the abutments on either side of the bridge, and partially into a vertical load on the arch supports. This design allows arch bridges to span considerable distances and carry heavy loads.
Here's a breakdown of key aspects of arch bridges:
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Structure: The fundamental structure is the arch itself, typically made of materials like stone, concrete, steel, or timber. The arch is supported by abutments, which are strong foundations that resist the horizontal thrust exerted by the arch.
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Load Transfer: When weight is applied to the arch, it is distributed outwards along the curve of the arch towards the abutments. The abutments then resist this outward force, preventing the arch from collapsing.
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Materials: Historically, arch bridges were often constructed of stone or brick. Modern arch bridges utilize reinforced concrete and steel for greater strength and longer spans.
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Types of Arch Bridges: There are several types, including:
- Deck Arch Bridge: The deck (roadway) is located above the arch.
- Through Arch Bridge: The deck passes through the arch.
- Tied-Arch Bridge: The arch is connected to the deck by vertical ties, which absorb the horizontal thrust.
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Examples: Famous examples of arch bridges include the Ponte Vecchio in Florence, Italy, and the Sydney Harbour Bridge in Sydney, Australia.
