A Caltrans spokesman said today that non-standard weld connections that were used to hold road deck sections together on the new eastern span of the Bay Bridge won’t affect the bridge’s performance during earthquakes.
“This is not an issue,” spokesman Andrew Gordon told reporters at a briefing at a Caltrans office in Oakland near the eastern side of the Bay Bridge.
Gordon admitted that there are some “misalignments” on the new span and that Caltrans “in some cases” exceeded an American Welding Society code section that says the vertical gap between two pieces of steel on a bridge can be no more than an eighth of an inch.
But he said members of Caltrans’ seismic safety review panel approved those exceptions because they believe the misalignments and larger gaps will only result in “inconsequential damage” in the event of an earthquake.
Gordon said, “At most there will only be an 8 millimeter difference between two deck sections and the public doesn’t see it and it doesn’t affect the public’s ability to drive on those sections.”
He said there are only “minor issues” on 10 of the 26 connections on the new eastern span and those issues are only on 7 percent of the total area of those 10 sections.
Commenting on another topic, Gordon said Caltrans has had “encouraging” test results that show that bolts that secure earthquake shock absorbers to the deck of the eastern span hold up well when placed under increased tension.
Last March, about one-third of the initial batch of 96 bolts that secure the shock absorbers to the deck failed when they were tightened. Caltrans figured out a temporary solution that allowed the new eastern span to open on schedule last Labor Day and completed a permanent fix in December.
Gordon said the recent tests involved a total of 2,600 bolts.
Jeff Shuttleworth, Bay City News