HQ Address: 2440 West Majestic Park Way, Tucson, AZ 85705

HJ3 has been strengthening corroded bridges with carbon fiber for a while now, and the results have been impressive. Throughout the years, carbon fiber has really proven itself to be an innovative rehabilitation material, but we never seem to hear about bridges that are actually constructed with carbon fiber reinforced polymers (CFRP). But why? It seems logical that if reinforced concrete structures could be protected from corrosion right off the bat, the structure’s life expectancies should surpass 70 or 80 years, doubling or even tripling the life expectancies of current designs, right? So have we not heard of these bridges because they don’t yet exist? Well, as it turns out, there are several bridges all over the world that were initially constructed with CFRP materials.

CFRP cable strands and tendons were used in the construction of the Bridge Street Bridge. Credit: michigan.gov
CFRP cable strands and tendons were used in the construction of the Bridge Street Bridge. Credit: michigan.gov

The first CFRP bridge to be built in the United States was the Bridge Street Bridge (aptly named, don’t you think?), in Michigan.  It was designed and built by researchers at Lawrence Technical University in 2003, and replaces traditional black steel reinforcement with a combination of stainless steel and carbon fiber materials.  The carbon fiber components include both straight and bent bars (for non-tensioned reinforcement), as well as pre-tension carbon fiber strands (used in a manner similar to steel pre-tensioning strands in concrete beams), prestressing CFRP tendons and non-prestressing carbon fiber composite cable strands (to replace steel bars and tendons), as well as carbon fiber mesh fabric.  11 years after its construction, Michigan governor Rick Snyder has commended the success of the bridge, referring to it as “the bridge of the future.”
 
Lifting the CFRP bridge deck into position took less than 30 minutes. Credit: fiberline.com
Lifting the CFRP bridge deck into position took less than 30 minutes. Credit: fiberline.com

CFRP bridges are also prevalent in Europe.  While many of them are footbridges, used primarily for pedestrians and bicyclists, their success will likely transition into more road bridges in the near future.  One such road bridge, The West Mill Bridge, in Oxford, UK, has been described as “one of Europe’s most advanced highway bridges” for its CFRP construction, even though it’s only 10 meters long.
 
 
 
 
The West Mill Bridge is "one of Europe's most advanced highway bridges" Credit: Composites UK
The West Mill Bridge is “one of Europe’s most advanced highway bridges” Credit: Composites UK

Built in 2002, the bridge utilizes composites in its load-carrying beams, side paneling, and bridge deck.  The bridge’s edge beams, footpath, and two crossbeams at each end are constructed of concrete, while its crash barrier is made of steel.  The wearing surface itself is actually a polymer concrete as well.  All load-carrying elements are made from polyester, glass, and carbon fibers, and the entire bridge was built at a temporary factory, located at the bridge site.  After construction was finished, it took less than 30 minutes to lift it and set it into position.   Building a bridge with CFRP components comes with several advantages:

  • Short construction phase
  • Fast installation
  • Resistant to water, de-icing salt, and frost
  • Corrosion-resistant
  • Much longer service life
  • Minimal maintenance costs
  • Low operation costs
  • Less traffic problems due to maintenance
  • Reduced mass, allowing for smaller cranes, simplified transportation, easier installation, and reduced assembly time and cost
  • Superior durability
  • Resistant to chemicals from spillages
  • New aesthetic possibilities
  • More efficient geometrically

Want more information about using carbon fiber for bridge repair or construction?  Email us today!  info@hj3.com