The pedestrian walkway that collapsed in Florida on Thursday, killing multiple people, was a first-of-its-kind “instant bridge” — which was built using a radical new approach known as “accelerated construction.”

Installed this past Saturday, the 950-ton structure was erected in just a “few hours” under orders from MCM Construction Management and Florida International University, where the bridge is located.

“FIU is about building bridges and student safety. This project accomplishes our mission beautifully,” school 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 walkway was supposed to link FIU’s Modesto A. Maidique Campus to the Miami suburb of Sweetwater, where roughly 4,000 students reside.

Workers installed the main span, which collapsed Thursday, over the Tamiami Trail and expected to open up the entire bridge by early 2019.

The piece measured 174 feet from end-to-end and was built using Accelerated Bridge Construction (ABC) methods, which are being “advanced” at the FIU’s Accelerated Bridge Construction University Transportation Center (ABC-UTC).

“This method of construction reduces potential risks to workers, commuters and pedestrians and minimizes traffic interruptions,” the school said in a press release following Saturday’s installation.

“The main span of the FIU-Sweetwater UniversityCity Bridge was installed in a few hours with limited disruption to traffic over this weekend.”

Workers constructed the large stretch of walkway on the side of the Tamiami Trail, while the support columns were said to have been erected in place. The main span was then picked up by special gantry cranes and lowered into position.

Atorod Azizinamini, chair of FIU’s Civil & Environmental Engineering Department and one of the world’s leading experts on Accelerated Bridge Construction, hailed the $14.2 million project — calling it an “outstanding example of the ABC method.”

“Building the major element of the bridge — its main span superstructure — outside of the traveled way and away from busy Eighth Street is a milestone,” he said.

Local officials closed traffic along Southwest Eighth Street on Friday night until 5 a.m. Monday before eventually opening the road back up to the public. It’s unclear if any testing was done to ensure that the area was safe.

Both FIU and the companies involved in the bridge’s construction have released statements, saying they were “stunned” and “shocked” by what happened Thursday.

The cause of the collapse remains unclear. The National Transportation Safety Board plans to send a 15-person team down to Miami to investigate.