After 25 years, severe corrosion to Pittsburgh’s Fort Pitt Tunnel, created a safety hazard for the 138,000 cars that pass through daily. The original carbon steel anchors and angles rusted and grew in thickness, causing 400 granite slabs to crack at the edges. The Pennsylvania Department of Transportation (DOT) chose a non-corroding stainless steel anchoring system to support the new granite facade.
Cost Company of Pittsburgh, PA used more than 90,000 pounds of Type 316 stainless steel anchors and angles for the repair job. Type 316 is a commonly used chromium nickel stainless steel with molybdenum added to further enhance corrosion resistance. According to Cost Company engineers, the new stainless steel anchoring system is designed to “outlive the granite.”
The tunnel restoration is a cost-effective solution that saved the granite facade of this Pittsburgh landmark. The Pennsylvania DOT specified stainless steel so the next generation of motorists and engineers need not worry about the Fort Pitt Tunnel.
