Engineer called to report cracks in Florida bridge days before it collapsed
Workers stand next to a section of a collapsed pedestrian bridge on Friday near Florida International University in Miami. (Wilfredo Lee / Associated Press)
Two days before a pedestrian bridge collapsed onto a busy roadway at Florida International University, an engineer working on the project called the Florida Department of Transportation to say he had observed cracking on the span, the department said late Friday. It was not immediately clear whether cracking contributed to the collapse, which killed at least six people and injured nine others.
The call came in to a landline phone at the department and went unanswered because the employee assigned to the phone had been out of the office on assignment, the department said. It released a transcript of a voicemail the engineer had left.
"Hey Tom, this is Denney Pate with FIGG bridge engineers," the voicemail said. "Calling to, uh, share with you some information about the FIU pedestrian bridge and some cracking that's been observed on the north end of the span, the pylon end of that span we moved this weekend. Um, so, uh, we've taken a look at it and, uh, obviously some repairs or whatever will have to be done but from a safety perspective we don't see that there's any issue there so we're not concerned about it from that perspective although obviously the cracking is not good and something's going to have to be, you know, done to repair that."
At a news conference Friday night, officials from the National Transportation Safety Board said they could not yet say whether cracking contributed to the collapse, the Associated Press reported. They also said workers were trying to strengthen a diagonal member on the bridge when it collapsed.
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(Los Angeles Times)
Both the NTSB and the Miami-Dade Police Department have launched investigations into the tragedy.
"Right now, we just want to find out what occurred, what caused this collapse to occur," said Miami-Dade Police Department director Juan J. Perez at a news conference earlier Friday. "We're gonna have to start from the beginning, from contract, all the way to the end, when the incident happened."
Miami-Dade County Deputy Mayor Maurice Kemp added that no survivors were thought to remain in the rubble, which crushed at least eight vehicles like soda cans, and that emergency efforts had switched to recovering the remaining victims' bodies.
"We want to ensure that this type of accident doesn't happen again locally or anywhere in this country," Kemp said.
The tragedy focused attention on a relatively new and novel form of bridge construction.
In 2010, a group of bridge engineering experts met at Florida International University in Miami to push an idea: Infrastructure around America was crumbling, and the nation needed new bridges. A lot of them.
But bridges often took a long time to build, leading to clogged traffic, irritated commuters and more workers working in dangerous areas where they could get hit by cars.
So the experts created an academic center to advance a technique called Accelerated Bridge Construction, in which bridges are built off-site and, when ready, moved to their final locations in one piece, with disruption lasting days or less.
That seemingly marvelous process unfolded at FIU this month, as officials installed the 174-foot, 950-ton pedestrian bridge over a weekend. On Thursday afternoon, the bridge, which had not yet been opened, collapsed onto passing traffic below.
More than 100 bridges around the U.S. have been installed using the new construction technique, according to FIU's Accelerated Bridge Construction University Transportation Center, which the engineers founded in 2010.
One of the most recent projects to use Accelerated Bridge Construction was the new Sacramento Wash Crossing on historic Route 66, along Arizona's western border, about 270 miles east of Los Angeles.
The road was closed for three and a half days to install the bridge last year. Officials estimated that traditional techniques would have lasted three months.
Saiid Saiidi, a professor of civil and environmental engineering at the University of Nevada-Reno, said that there was "nothing wrong inherently" with bridges built using Accelerated Bridge Construction techniques and that the chances of collapse are no greater compared with traditional methods.
(Los Angeles Times)
"The internal connections and the way you put them together" are the same, Saiidi said, though he said the new methods can be more challenging. "You have to build them right, you have to design them right, so if anything, ABC bridges require a lot more care and the work is more carefully done."
The $14.2 million bridge at FIU was designed by FIGG Bridge Engineers Inc., and built by MCM Construction with help from funding from a U.S. Department of Transportation TIGER grant, or Transportation Investment Generating Economic Recovery grant.
"This is an unprecedented event," FIGG said in a statement. "No other bridge designed by FIGG Bridge Engineers has ever experienced such a collapse."
FIGG was chosen to design the new Interstate 35W bridge in Minneapolis after the previous bridge, which had been built in the 1970s, collapsed in 2007, killing 13 people.
In a statement, MCM, the contractor, said it was "fully cooperating" with the NTSB's investigation and that it was "just heartbroken" for the victims. "We have been in business for more than 35 years, and safety has always been our number one priority," the company said.
The FIU-Sweetwater UniversityCity Bridge was initially built alongside Southwest 8th Street, an eight-lane thoroughfare, starting in spring 2017. Then, on March 10 — a Saturday — the bridge was lifted from its supports, rotated 90 degrees, and then placed over 8th Street.
University officials initially hailed the process in a statement, saying the "method of construction reduces potential risks to workers, commuters and pedestrians and minimizes traffic interruptions."
"FIU is about building bridges and student safety. This project accomplishes our mission beautifully," FIU President Mark B. Rosenberg said in a statement. "We are filled with pride and satisfaction at seeing this engineering feat come to life and connect our campus to the surrounding community where thousands of our students live."
The bridge was expected to open in early 2019 after further modifications.
After the collapse, Rosenberg filmed a video response promising a "thorough investigation" into the "tragic accident," saying, "It's exactly the opposite of what we had intended, and we want to express our deepest condolences to the family and loved ones of those who have been affected."
(Los Angeles Times)
Sen. Marco Rubio (R-Fla.) tweeted that "the cables that suspend the #Miami bridge had loosened & the engineering firm ordered that they be tightened. They were being tightened when it collapsed today." Rubio did not offer further details, and neither FIGG nor MCM firms immediately responded to queries about the senator's claim.
The director of FIU's Accelerated Bridge Construction University Transportation Center, Atorod Azizinamini, who was quoted in the university's news release initially praising the bridge, did not response to a request for an interview.
An FIU spokeswoman instead responded and directed The Times to an outside expert, declining to comment further.
Matt Pearce is a national reporter for The Times. Follow him on Twitter at @mattdpearce.
UPDATES:
7:10 p.m.: This article was updated with a report of a phone call about cracking on the bridge.
This article was originally posted at 4:10 p.m.
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