NTSB To Determine Likely Cause Of FIU Bridge Collapse

On Tuesday, the public is expected to hear an objective opinion from the National Transportation Safety Board, which has reviewed and tested vast amounts of evidence from the failure

The blame shifting began even before the dust cleared from the March 15, 2018 collapse of what was to be Florida International University’s showcase pedestrian bridge over Southwest Eighth Street.

The Florida Department of Transportation within hours tried to distance itself from the disaster, which killed six, even though a top FDOT bridge engineer in Tallahassee had approved much of the design for years.

Also, an FDOT consultant was in a meeting that morning where cracks in the bridge were discussed and an ill-fated effort to address the cracking was revealed, without anyone present suggesting the busy road below be closed.

In ensuing months, the builder would blame the designer, the designer would blame the builder, and several others would point fingers at an engineering firm that was supposed to do an independent review of the designs.

On Tuesday, the public is expected to hear an objective opinion from the National Transportation Safety Board, which has reviewed and tested vast amounts of evidence from the failure, including interviews with some key players.

The NTSB, at a public hearing at its Washington, DC, headquarters, is also expected to issue recommendations designed to prevent what happened last year from ever happening again.

One issue certain to emerge in that vein: what should engineers, builders, inspectors and government agencies do when concrete structures over roadways start to crack, as the FIU bridge started to do weeks before it was lifted from its roadside construction site and placed on supports over Eighth Street.

The first serious alarm over cracks occurred on Saturday, Feb. 24, when workers removing forms that shaped the concrete ran from under the span when they heard a loud cracking sound. An inspection showed a separation had formed where the deck met one of the diagonal trusses that ran down the center of the bridge.

But engineers who designed the bridge said that crack was not unexpected and could be patched up.

Once the bridge was put in place, cracking grew worse after steel bars providing support to the ends of the bridge during its move were de-tensioned by a sub-contractor, as called for in the plans.

"It cracked like hell," one worker for the subcontractor texted his superior, along with a photo showing severe cracking.

Yet no one involved thought to consider closing the roadway until the issue could be resolved, according to records released so far.

It was a previously unplanned order to re-tension the steel rods on the northernmost truss, an effort to restore it to its condition prior to the de-stressing, that was being carried out when the 174-foot-long main span collapsed.

When it comes to determining probable cause for the disaster, previous preliminary statements and the release two weeks ago of thousands of pages of factual record suggest the NTSB will primarily blame a deficient design by FIGG Bridge Engineers.

The board, based on analysis by engineers with the Federal Highway Administration, has said FIGG overestimated the capacity of a critical section of the bridge to withstand forces that would converge there. It is the same area that failed as workers were carrying out FIGG’s orders to retighten steel bars running through a diagonal truss at that spot.

The FHWA engineers also said FIGG’s plans underestimated the load that would be borne at that critical junction, where the truss met the deck at the north end of the span, during certain phases of construction.

But FIGG disputes that, saying the bridge would not have failed if the main contractor, MCM, made sure concrete on the deck was properly roughened before more concrete forming the diagonal truss was poured above it days later, creating what is called a "cold joint."

For its part, MCM produced evidence suggesting the area was roughened, and said FIGG’s miscalculations caused the bridge to fail anyway.

Other analysis obtained by both the NTSB and FIGG indicate the cold joint was not significantly roughened, though the FHWA engineers repeatedly cite what they say were FIGG’s design errors as a primary cause.

Both FIGG and MCM blame another engineering firm, Louis Berger, for not doing an independent, thorough review of FIGG’s plans, as FDOT insisted because of the complexity and lack of redundancy in the plans.

Louis Berger is the only one of about two dozen defendants in wrongful death and personal injury cases that has not agreed to a tentative settlement that would pay victims and families tens of millions of dollars in damages.

That settlement is being overseen in bankruptcy court, as part of the Chapter 11 reorganization sought by MCM, which was known as Munilla Construction Management before changing its name after the collapse.

FIU continues to seek payment from issuers of bonds that were supposed to insure FIU against just such a failure, and continues to plan to erect a bridge across the busy road, according to transcripts of court hearings.

The university agreed to forego up to $5 million it says it could have sought from MCM’s insurers, a move that increased to $42 million the pool of MCM insurance money available to the victims.

But now, an FIU attorney said in court, a dispute Involving FIU’s efforts to collect on those bonds could complicate matters and further delay payment to victims through the bankruptcy court proceedings.

If no settlement is approved by the bankruptcy court by January, Miami-Dade Circuit Judge Jennifer Bailey has said she would start to set trial dates in the personal injury and wrongful death cases.

Contact Us