Effects of Cutting a Strand Was:I am a Professional Engineer
Effects of Cutting a Strand Was:I am a Professional Engineer
(OP)
In response to ramezkamel's question in the previous thread.
A good example of what happens when the strand is cut or broken is the pedestrian walkway collapse at a Racetrack in North or South Carolina. I don't remember if the bridge was pre or post stressed but I don't think that matters. ENR (www.enr.com) reported on it in May(?). IIRC, the Charleston, SC paper had some very good articles on what happened, etc.
Basically, the strand broke; the load was transferred to the other strands, exceeding their yeild strength; they stretched; the bridge buckled in the middle; about 10 seconds later it came to rest on the freeway below. It was not an explosive collapse but a slow (relatively) stretching of the other cables until the halves formed a V. Obviously, without the steel we would have had lots of little pieces of rubble instead of the intact halves.
A good example of what happens when the strand is cut or broken is the pedestrian walkway collapse at a Racetrack in North or South Carolina. I don't remember if the bridge was pre or post stressed but I don't think that matters. ENR (www.enr.com) reported on it in May(?). IIRC, the Charleston, SC paper had some very good articles on what happened, etc.
Basically, the strand broke; the load was transferred to the other strands, exceeding their yeild strength; they stretched; the bridge buckled in the middle; about 10 seconds later it came to rest on the freeway below. It was not an explosive collapse but a slow (relatively) stretching of the other cables until the halves formed a V. Obviously, without the steel we would have had lots of little pieces of rubble instead of the intact halves.




