Photo credit: http://time.com/5201941/fiu-pedestrian-bridge-collapse-florida-international-university/ (Time Magazine)
On Thursday, March 15th, Florida International University's pedestrian bridge in Miami collapsed, leading to 6 fatalities, and 10 injuries. Engineering and structural failures have been blamed for the fall of the $14.2 million, 950-ton "instant bridge". Set to open next year, the student walkway was built by two experienced Florida construction firms, Figg Bridge Design and MCM construction. Both companies have embarked on numerous projects throughout the United States.
"Instant bridge," also known as "accelerated bridge construction," was the method employed to build the FIU crossing. The purpose of this technique is to execute the majority of bridge construction off-site prior to installation. According to the Department of Transportation's Federal Highway Administration, the instant bridge method is "a paradigm shift in the project planning and procurement approach." Moreover, accelerated bridge construction is much faster than traditional methods, it minimizes travel related risks on the road, and decreases delays as well.
As much as the FHA and construction agencies love to boast about the "instant bridge" technique, after reflecting upon the incident in Florida, it is evident that this method is far from infallible. Former president of the American Society of Civil Engineers,
Andy Hermann, highlighted the fact that multiple variables could have triggered the bridge collapse, and at the moment, it is difficult to pinpoint the source of catastrophe.
"It could be materials, it could be construction technique, it could be the engineering design itself. With the ABC type of construction, there are design loads that have to be taken into account for the actual moving of the bridge. ABC construction essentially builds a bridge off-site and then moves it into place for its final position. And when you do that you have different load points, different supports for the bridge that are different than the final supports. So you have to take account for that when you design the bridge," stated Hermann.
The FIU bridge collapse is currently being investigated. According to Miami-Dade Mayor Carlos Gimenez, a possible trigger mechanism for the fatal incident could have been a stress test that was performed on the span of the bridge. After examining the design of the walkway and inspecting the aftermath of its destruction, Robert Bea, professor of engineering and construction management at the University of California, Berkeley, stated to the Associated Press that "Innovations take a design firm into an area where they don't have applicable experience, and then we have another unexpected failure on our hands."
Photo credit: http://abcnews.go.com/US/pedestrian-bridge-florida-international-university-collapses/story?id=53774444 (ABC News)
Apparently, both Figg and MCM have been involved in previous bridge failures. According to the Miami Herald, Figg was slapped with four violations in 2012 by the Virginia Department of Labor after a 90-ton chunk of concrete plummeted from a bridge that was under construction near Norfolk. The company was also fined a hefty $28,000 by the Department of Labor after unauthorized and improper modification of a girder – which caused the 2012 bridge collapse. MCM is also under fire, as a lawsuit that was filed earlier this month blames the company for hiring “incompetent, inexperienced, unskilled or careless employees." According to the Occupational Safety Health Administration, over the past five years, MCM has blown through 11 safety violations, and fines that exceed over $50,000 total.
Despite the accusations being pointed at both construction firms, Figg expressed that, "In our 40-year history, nothing like this has ever happened before," and MCM stated that, "MCM is a family business and we are all devastated and doing everything we can to assist. We will conduct a full investigation to determine exactly what went wrong and will cooperate with investigators on scene in every way.”
FIU school president Mark B. Rosenberg has recently stated that the school community is currently in the stage of “immense sadness, uncontrollable sadness.” Rosenberg further stated that “We're committed to assist in all efforts necessary, and our hope is that this sadness can galvanize the entire community to stay the course, a course of goodness, of hope, of opportunity."
At the moment, the 6 dead bodies discovered in the rubble have not yet been identified, and rescue teams continue to sort through the wreckage in pursuit of signs of life.