Arch bridges are characterized by their arches or curved designs that give them strength. As a result of this curving or bending, the load force isn’t pushed straight downwards, or rather, it is carried or transferred along the arch curve to the supports or abutments(桥墩)present at each end of an arch bridge. This semi-circular structure thus enables a higher level of resistance to the bending force which may have altered or changed the bridge. In other words, the force acting on the bridge horizontal is distributed equally.
Also, there are many different building materials for arch bridges. They can be built using a wide range of materials that include natural ones like stones, bricks, etc., as well as man-made materials like reinforced concrete or steel. Natural or local materials aid in sustainability and are strong in compression.
In addition, these bridges tend to strengthen with increased usage. Ancient arch bridges had a keystone, which was once put in an arch bridge and could undergo compression, thus making the bridge stronger. Furthermore, the abutments also help enhance the sustainability of these bridges. A great deal of deadweight is introduced above each arch, thus supporting loads as well as gaining strength.
Despite the above various advantages of the arch bridge structure, there’re also many disadvantages that cannot be ignored. For example, these bridges have a limited span(跨度)length. The sizes of arches and the materials used can determine the weight that an arch bridge is capable of bearing. Such bridges can be built only in certain sizes.
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