Thirty-two large bolts on the new eastern span of the Bay Bridge have been discovered to be faulty, a Metropolitan Transportation Commission spokesman said this morning.
The bolts, ranging from 9 to 17 feet in length, are located near where the new span’s self-anchored suspension span meets its skyway, MTC spokesman John Goodwin said.
There are 288 anchoring bolts that tie the road decks down to a supporting pier below, and 32 have popped out a couple of inches since they were tightened, Goodwin said.
Over the course of the past month, the batch of bolts, which were manufactured in 2008, have failed to tighten properly due to excessive hydrogen in the steel, which causes embrittlement, he said.
“It’s not common, but it does happen,” Goodwin said, noting that the fault may have occurred during the manufacturing or galvanizing process in Ohio, where the bolts were made.
Based on preliminary estimates, the error may cost an extra $1 million to $5 million to correct because the giant bolts will need to be remanufactured specifically for the project, Goodwin said.
“We won’t be able to swing by Orchard Hardware,” he said.
The commissioners will get a full briefing on the situation at a meeting at 9:30 a.m. at 101 Eighth St. in Oakland.
Hannah Albarazi, Bay City News
Elsewhere: Giant Bolts Snap On New Bay Bridge Eastern Span [CBS5]
Bay Bridge inspections: busted bolts [Chron]