PITTSBURGH — For experts, it’s way too early to reach a conclusion on the cause of the Forbes Avenue bridge collapse on Friday.
The National Transportation Safety Board arrived at the scene hours later to launch an investigation that could take 18 months or longer.
But some engineering experts interviewed by the Pittsburgh Post-Gazette who reviewed prior inspections and saw news media photos of the wreckage have theorized about what went wrong in the morning hours when 10 people were injured and seven vehicles, including a Port Authority bus, were left in the rubble.
