Silver Bridge collapsed in seconds — a tiny crack in one eyebar killed 46 people

The Silver Bridge opened on 30 May 1928, spanning the Ohio River between Point Pleasant, West Virginia, and Gallipolis, Ohio. It was an eyebar-chain suspension bridge — a design that used a series of linked steel eyebars to form the main suspension chains, rather than the more common wire cable. The bridge was designed by the J. E. Greiner Company and built by the American Bridge Company. For 39 years it carried US Route 35 without incident, a crucial link for the region.

On 15 Dec 1967 at 5 PM, during rush hour, the bridge collapsed in less than 60 seconds. The cause was a single eyebar — number 330 on the Ohio side — that had developed a tiny crack only 0.1 inches deep. The crack formed from decades of fretting wear where the eyebar pin sat, and grew through stress corrosion until the bar fractured. Because the bridge used only two eyebars per suspension link, when one bar failed the entire load transferred to the other, which immediately fractured as well. The suspension chain unzipped, the bridge twisted and fell into the river.

Forty-six people died — 44 bodies were recovered, two were never found. The NTSB's 1970 report confirmed the eyebar failure and criticised the design's lack of structural redundancy. The disaster directly led to the Federal-Aid Highway Act of 1968, which created the National Bridge Inspection Standards, mandating regular inspection of all US highway bridges for the first time. The Silver Memorial Bridge opened in 1969 to replace the lost crossing.