Using Carbon Fiber to Support and Extend the Lifespan of Bridges

Because of its strength, unobtrusive design and cost effectiveness, carbon fiber has become increasingly popular in a variety of large infrastructure projects, including bridges.

In the United States, we have plenty of aging infrastructure. As of 2021, 42% of the nation’s bridges were more than 50 years old and 7.5% were considered structurally deficient.

In some cases this can necessitate weight limits or lane closures if the bridge has weakened enough where it can no longer support its standard traffic volume.

This, along with the cost of replacing the full bridge, is why a growing number of areas are looking to strengthen bridges in order to extend their lifespan. In some cases this can be done with carbon fiber.

Using Carbon Fiber to Strengthen Bridge Pier Caps

Similar to using carbon fiber to wrap columns to increase load capacity by providing additional confining strength, carbon fiber can be used to increase the load capacity of bridge pier caps.

After first using epoxy injections to repair any cracking, the bridge pier caps can be fully encapsulated with carbon fiber.

Carbon fiber is ideal for strengthening pier caps because it is easy to wrap around different shapes without leaving gaps that could become points of structural weakness.

One item to be concerned about: The epoxy adhesive used to secure the carbon fiber to the bridge could weaken under the sun’s ultraviolet rays. It is important to cover the carbon fiber with a UV-resistant product.

Other Bridge Applications

If any bridge columns need reinforcing, carbon fiber can again be used to increase the load-bearing capacity by providing additional confining strength.

Carbon fiber strips attached length-wise along the bottom of beams running parallel to the ground can also improve the strength of the beams.