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.

　　When natural materials are used for building, additional maintenance or care is needed. This is because the impact of wind forced on the structure or the wind load causes an arch bridge to bend and move. Thus, frequent care becomes necessary. This may further give rise to extra maintenance costs.

　　Arch bridges have a long construction time. For the proper and normal functioning of these bridges, they have to be built in a particular way. Thus, their construction requires more time, mostly noticed in the case of natural materials. Also, more labor may be required.

　　Arch bridges can be constructed in only certain locations where the foundations on both sides are solid and stable. This is because this type of bridge needs more support from its sides.

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