Arch bridges are known as one of the oldest types of bridges known to man. They have been utilized for thousands upon thousands of years, and the design hasn’t changed much, even to today. They are characterized by using arches, which are semicircles, at the base of the bridge to increase it’s strength and durability. However, nothing is perfect, as many of us are aware, and arch bridges have their fair share of downfalls. The best way to understand the best uses, and the worst, for arch bridges is by looking at the good and bad things that come with them.
The Pros of Arch Bridges
1. The More They Are Used, The Stronger They Become
One of the largest advantages that come from the use of arch bridges is due to the keystone that is placed right on top. This stone, which is what vehicles pass across, becomes more and more compressed with the more weight it sustains. This compression leads to a more solid and stable bridge.
2. A Wide Variety Of Building Material Options
Arch bridges can be successfully made with both natural and man made materials. This is one of the things that sets this type of bridge apart from others. Each individual building material also has it’s good and bad points. For examples, natural materials, such as stone, is much easier and cheaper to obtain, but cannot withstand as much force as man made materials, like steel.
3. Unique Design Gives It Above Average Resistance
The curved arch, which gives this bridge type it’s name, is the most valuable characteristic that this type of bridge has. The semicircle shape gives the bridge massive amounts of strength because the weight, or force, is distributed and diluted instead of being pushed straight down.
The Cons of Arch Bridges
1. Their Length Is Greatly Limited
Due to the complex structure and design of the arch bridge, as well as the massive amounts of material that is needed for construction, it’s span isn’t too impressive. The longer that the bridge is, the more arches have to be added, and the less stable the bridge becomes. Arch bridges are best suited for small distances, across rivers or creeks.
2. It Takes A Long Time To Build
The construction of an arch bridge is nothing to take lightly. It requires a great deal of time and effort to make an arch bridge happen. This is due to the complex design, and the precision that must be used while laying materials in order to ensure the bridge is safe.
3. Frequent Maintenance Can Be A Headache
Since natural materials are often used for the construction of arch bridges, maintenance is inevitable. This frequent upkeep adds to the already high cost of materials and construction that these bridges carry.
4. It’s An Expensive Project
Arch bridges are very solid, which means they require some pretty large quantities of building materials to make happen. The cost of an arch bridge, of course is determined by what type of material you choose to use, but generally, it is one of the most expensive bridges to construct.