Lightweight, durable, corrosion-resistant composites can take a beating.
Take a close look the next time you see a work crew erecting a new utility pole or making structural repairs to a bridge. The materials they’re using may be made from composites rather than the traditional steel, concrete or wood for stronger, more resilient infrastructure components.
Here’s a sampling of what’s happening.
Over the past few years, utility poles made from composite materials have withstood hurricanes and high winds that knocked down wooden poles.1 Utility companies and government agencies have taken notice.
In southeast Missouri, the local utility company is installing 45 composite utility poles along two highways. Since composite utility poles are more expensive than wooden poles, at least in upfront cost, the utility hopes to harden the electrical infrastructure by replacing every fifth wooden pole with a composite pole.
In May, local utility companies in the Rochester, New York, area agreed to spend $1,25 million to install utility poles made of composite materials. The state’s public service commission required the company to harden its infrastructure after a windstorm took down many wooden poles and cut off power to thousands of customers for days.
Hurricane Maria knocked out power to the U.S. Virgin Islands in 2017. The Federal Emergency Management Agency (FEMA) has authorized the Virgin Islands Water and Power Authority to replace 6 500 wooden poles with composite poles along critical feeder paths and key transmission circuits.4 Previously, FEMA only funded like-for-like replacements. The goal is to rebuild stronger so areas will be better prepared for natural disasters.
Composite materials are being used to repair bridges, roads and piers.
The Arizona Department of Transportation (ADOT) is using a type of composite — carbon fiber strips coated and strengthened with a reinforcing polymer — to fix girders on state highway bridges. ADOT crews wrapped damaged girders on two bridges with the material. The repairs took less time than rebuilding the damaged section of the bridge and have extended the life of the structures. One of the bridges has been moved off the long list of structurally deficient bridges thanks to the fix.
In the water, composites have been used for several years for sheet piling. More recently, the U.S. Army Corps of Engineers approved a composite wrap product as a preferred material for making emergency repairs to damaged piers.
The National Institute for Standards and Technology (NIST) is advocating for the wider use of composites for infrastructure repair. In testimony before Congress, Dr. Joannie Chin, deputy director of NIST’s engineering laboratory, explained that because composite components are lighter than traditional building materials, it takes less fuel to transport them to the jobsite, and lighter-duty equipment can be used to install them.
In addition, composite materials are stronger and longer-lasting than traditional building materials because they resist corrosion from weather and exposure to chemicals.
“The longer lifespans for infrastructure components that include advanced composites mean fewer service days lost to maintenance of the bridges, roads, dams, levees, highways, railroads, utility poles and other elements that support movement of the goods and services that underpin our economy,” Chin noted.
Bills recently introduced in the U.S. Senate and House of Representatives would provide funding to municipalities that use innovative materials like composites in infrastructure projects.
Freelance writer Mary Lou Jay writes about business and technical developments in a variety of industries. She has been covering residential and commercial construction for more than 25 years.
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