NTSB Plans Pittsburgh Bridge Collapse Meeting

FRIDAY, FEBRUARY 9, 2024


The National Transportation Safety Board has announced that later this month it will hold a meeting to determine the probable cause of the Fern Hollow Bridge collapse in Pittsburgh.

According to a report from CBS News Pittsburgh, the NTSB plans to hold a virtual board meeting on Feb. 21 at 9:30 a.m. to vote on final findings from the investigators, the probable cause and recommendations for the future.

A release from the NTSB adds that any additional information can be found in the public docket for the investigation, including detailed information, reports, interview transcripts and other investigative materials.

Additionally, a link to the webcast will be available shortly before the start of the meeting and can be found here.

NTSB Chair Jennifer Homendy will reportedly be available to media following the board meeting.

Bridge Collapse Background

On Jan. 28, 2022, the Allegheny County Police Department was notified about a partial bridge collapse over Frick Park. Emergency crews arrived at the Forbes Avenue Bridge, also referred to as the Fern Hollow Bridge, around Forbes and Braddock avenues.

Initial reports indicated that an articulated Port Authority bus and four passenger vehicles were on the bridge at the time of the collapse, along with a fifth passenger vehicle that drove off the east bridge abutment following the collapse. First responder crews rappelled 100 to 150 feet to reach victims, while others formed a “human chain” to rescue people from the bus.

A preliminary NTSB investigation reported that the bridge was an uncoated, weathering steel, three-span, continuous rigid “K” frame structure with two welded steel girders, welded steel floor beams and rolled steel stringers. The ends of the structure rested on reinforced concrete caps on stone masonry abutments, with each girder additionally supported by two inclined, welded and uncoated weathering steel frame legs on concrete thrust blocks.

According to the release, certain areas of the welded steel girders were identified as being fracture critical, but no primary fractures were found in those areas. Initial assessment indicates the collapse began at the west end of the bridge.

In May of that year, the NTSB provided an update on the recovery of structural components and tests currently being conducted to evaluated materials used when constructing the bridge, as well as a review of new footage recovered from a transit bus camera system.

Investigators reviewed video footage from the time of the collapse from two of the cameras on a Port Authority transit bus. The cameras, one forward-facing and one rear-facing the curbside, were determined to have “investigative value” with frames depicting events of interest.

The first frame, from the forward-facing camera, reportedly showed the bridge deck separating at the east expansion joint. The second frame, from the curbside camera, reportedly showed that, at nearly the same time, the west end of the bridge had already fallen off the west abutment.

Additionally, while the preliminary report listed ten vehicle occupants as being injured during the bridge collapse, further investigation had confirmed a total of nine occupants in six vehicles, including the Port Authority transit bus. Of the injuries, two vehicle occupants sustained serious injuries, two injuries were minor, four were uninjured and the injury status of one is unknown.

That same month, a newly released inspection document revealed that the Fern Hollow Bridge had “major decay” prior to its collapse, including exposed rebar, corrosion, holes in the steel crossbeams and spalling in the bridge deck.

In December 2022, officials opened the new Fern Hollow Bridge, after the construction of the replacement structure was completed less than a year after the original bridge’s collapse in January. The bridge is currently open to a single-lane of bi-direction traffic.

In December 2023, an investigation from Scripps News using newly released federal data reportedly showed the unexpected difficulties in repairing bridges in the nation that are corroded, cracked and at a heightened risk of being shut down.

According to the report, billions of federal tax dollars are going towards fixing worn out bridges coast to coast as over 14,000 in all 50 states and Washington, D.C. have been ranked in poor condition for at least a decade.

Most recently, in January, new information was released from the NTSB, reportedly revealing failures by the city to properly service the structure and other bridges.

According to reports, these new documents showed that the consultant who led multiple inspections of Fern Hollow and other bridges told the city several times that it needed to keep drains clear of debris.

The city stated in response to these claims that it did not ask its maintenance contractor to clean expansion joints or drainage system on the Fern Hollow bridge in the three years before the collapse. Additionally, the city had admitted to not creating a maintenance schedule for expansion joints or stormwater drainage at bridges.

The NTSB documents reportedly raised concerns over the Pennsylvania Department of Transportation's bridge inspection procedures, as the city's bridge inspection consultant said he was allowed only two six-hour periods to inspect the bridge.

The thousands of pages of newly released documents in the investigation into the Fern Hollow Bridge collapse reportedly revealed two patterns: a lack of action and a lack of allocating necessary resources.

   

Tagged categories: Accidents; Bridges; Bridges; Corrosion; Corrosion protection; Department of Transportation (DOT); Infrastructure; Infrastructure; NA; North America; NTSB (National Transportation Safety Board); Program/Project Management; Quality control; Rebuilding; Rehabilitation/Repair; Roads/Highways; Transportation

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