Three pieces of an emergency repair to the Bay Bridge's cantilever section made over Labor Day weekend snapped and crashed onto the upper deck of the span late Tuesday afternoon, striking three vehicles and forcing the indefinite closure of the region's busiest bridge.
Caltrans officials ordered the closure of the bridge in both directions shortly after 7 p.m. and said they could not estimate when the bridge would reopen.
The pieces that snapped were two high-strength steel rods and a cross beam from a steel saddle, said Tony Anziano, Caltrans toll bridge program manager. Those parts were installed over Labor Day weekend during an repair job that delayed the reopening of the bridge following scheduled work.
The area of the bridge where the pieces broke off was where, over Labor Day weekend, crews found a critical flaw on a steel structural beam, called an eyebar, helping to hold up the eastern span.
The crack was discovered during the planned four-day shutdown of the span to install the 288-foot S-turn, but was unrelated to that project.
Caltrans engineers said then that there were enough safeguards in the bridge design that the crack could not have led to the bridge collapsing.
The problem forced officials to push back the announced reopening of the span while emergency repairs were made. Working nearly 70 hours nonstop, crews wrapped a steel brace around the broken beam to redistribute tension away from the damaged area. That brace was then attached to another one set lower on the span using steel rods.
In the end, the bridge reopened in time for most of the morning commute the day after Labor Day.