
An investigative update to the collapse of a pedestrian bridge under construction in Miami, FL, in March 2018 has determined errors were made in the design of the northernmost nodal region of the bridge where two truss members were connected to the bridge deck. According to the investigation, the design errors resulted in "overestimation of the capacity (resistance) of a critical section through the node comprised of diagonal member 11 and vertical member 12," and "apparent underestimation of the demand (load) on that same critical section.
According to the FHWA evealuation, the cracking observed in that node prior to the collapse is consistent with these identified design errors.
(more investigation updates to the FIU pedestrian bridge collapse...)