Carbon fiber – new muscle for old bridges

Forget the concept of “supporting wall.”

With the aid of carbon fiber it is now possible to reinforce concrete, making a concrete bridge, for example, considerably stronger.

The method has been used to reinforce the much discussed trolley-car bridges in Stockholm, Sweden as well as many buildings and construction projects all around the country. Several bridges along the Ore Railroad in northern Sweden have also been strengthened with carbon fiber.

The strength of carbon fire makes it a highly effective reinforcement for concrete. By gluing a thin layer of carbon fiber to an existent concrete bridge, it is possible to make the bridge stronger. In a new doctoral dissertation at Luleå University of Technology, Anders Carolin presents how the method works and what potential it has.

“Now supporting walls are no longer holy. With reinforcement it is possible to rebuild structures that previously required costly and major intervention,” says Anders Carolin.

The method of reinforcing concrete with carbon fiber has proven to be cheaper and more effective than earlier means of reinforcement. Since many constructions around us are paid for by rent or taxes, it is clearly in our own best interest to choose the cheapest solution–in the long term.

Besides reinforcement, the method is used to make it possible to install elevators and ventilation equipment, interventions that used to be extremely costly and inconvenient.

“Many bridges in Sweden are in need of reinforcement or replacement. For economic and environmental reasons it’s not possible to replace them all. Instead, reinforcement is a necessity in order to make bridges safe and reliable,” says Anders Carolin.