This post is a re-publication of an article from the Arizona Daily Star by Arthur H. Rotstein of the Associated Press

Hamid Saadatmanesh has been called Dr. Carbon. Some people might call him the bridge doctor.

The University of Arizona civil-engineering professor has made a career of developing methods to use carbon fiber to strengthen concrete, steel and brick on bridges and other structures that have been damaged or otherwise fallen into disrepair.

Among some high points to date:

  • Getting the California Department of Transportation to use carbon-fiber fabric to wrap around bridge columns damaged by the 1989 Loma Prieta earthquake in the San Francisco area.
  • Demonstrating that a concrete block wall could withstand an explosive blast from 230 pounds of TNT after it had been covered with carbon fiber and a special epoxy he formulated.

Saadatmanesh (Sah-DOT-man-esh) said he stumbled onto his key findings by chance.

Saadatmanesh had just arrived at the university in the summer of 1987 after earning his Ph.D. at the University of Maryland to work on rehabilitation of bridges.

He described himself as “a young, nervous assistant professor trying to look for something to do, to get a grant” that would lead to job security and eventually tenure.

One day, he noticed corroded steel rebar — bars of steel used in reinforced concrete or reinforced masonry — next to the engineering building.

“Suddenly, it sparked in my mind that this is a problem all over the world, that there are billions of dollars actually spent every year on deterioration of structures because of (rebar) corrosion,” Saadatmanesh said.

That’s when he thought about making a product that doesn’t corrode, ultimately settling on plastic rebar reinforced with carbon fibers, providing strength, durability and resistance to corrosion.

But given the limited application for rebar and the fact that corroded steel rebar can’t be extracted from concrete, Saadatmanesh said he turned his attention more to carbon fibers, which were being used in the aerospace industry but not in civil engineering or construction.

Among its qualities, carbon fiber is lightweight, noncorrosive and much stronger than steel. “On the average, the material strength of carbon is 10 times stronger than your average steel,” he said.

Saadatmanesh has strongly advocated the transfer of advanced composite materials technology in use in the aerospace industries into construction, for repair of public works and other infrastructure.

Saadatmanesh received eight National Science Foundation grants between 1990 and 1997, totaling more than $1.25 million to pursue his goals.

One grant went toward the TNT explosion demonstration.

With a special epoxy he developed after several years of research, Saadatmanesh bonded carbon-fiber sheets, which he calls carbon wrap, on the outside of corroded or cracked steel or concrete beams, columns or slabs, right over the corroded elements.

Today, the professor has his third company, Carbon Wrap Solutions LLC, and sells the materials to contractors across the country.