Here is link to some raw video. http://www.globaltvbc.com/video/raw...nn+bridge/video.html?v=2195192456#only+online They were placing a 90 ton bridge section when somthing failed. As I don't understand this type of crane, perhaps someone would like to explane and I would better understand. sorry about the comercial, out of my control. muzy
I've seen one like this used to put together the light rail bridges from SeaTac Airport to South Seattle. On this unit it looks like the forward support section just rolled over and let the front part of the gantry settle down. The ones used here were set up on the vertical supports and a trolley in the center would move horizontal components from the completed sections to the open space of the incomplete sections. As each section was completed, they just traveled the gantry and supports onto the newly completed part and rigged for the next span to assemble. It worked real slick down here but they were putting up rail lines and not automobile bridge sections. Thanks for the link.
Thanks John. Seeing it in action would clear it all for me. muzy
Stuff like this almost always turns out to be human error in some way. Bad judgment or miscalculations, over loads, skipping a step in one of the operational sequences, a short cut, or an over sight some where. We have a way of messing things up royally even tho our cranes can get the job done without incident. At least there wasn't any blood shed.
http://www.timescolonist.com/news/Crane+collapses+Port+Mann+Bridge+injuries/6133636/story.html some photos of the job before and after the accident
Nice link heavtlift, thanks. I thought I read somewhere that ther was a camera set up recording 24/7. Have not seen that yet. muzy