huangyhg

big dig boston ceiling collapse
killed one person. not sure if this is a structural issue but with "large concrete ceiling panels" it sounds like one.
...and they are going after whoever screwed up.
negligent homicide"fff">fff">
quote:
massachusetts state troopers and another worker (wearing hard hat) inspect hardware removed tuesday, july 11, 2006, from a big dig tunnel where cementfff">fff"> slabs fell late monday night in boston. the falling slabs crushed a passing car killing a woman and injuring her husband.
damn press and "cement vs concrete"!
from the photo of steel tie back (turnbuckle with clevise and pin arrangement), seems that two (2) epoxied anchors secured a fabricated t-plate to the concrete panel, and the pullout failure looks like possibly that the drilled holes were not cleaned correctly resulting in premature failure. speculation on my behalf, but i was expecting to see a cast-in insert to the panel and a pullout cone.
with all due respect to those with the hard job of investigating this tragedy....why is a state trooper inspecting anything?! structural engineers should be dispatched to the site to assist any transportation official with the appropriate actions such as closing roads etc.
regards,
qshake
eng-tips forums:real solutions for real problems really quick.
he probably just happened to be handy for a photo op.
i got the inpression it was the attachment to the concrete tunnel that failed, not the panel.
here's a good graphic link i copied from another thread/forum with a similar post:
state trooper because they are treating it as a crime scene.
i was reading the following in the standard times which the main newspaper for the southcost of mass.
"john christian, a geotechnical engineer hired to conduct an investigation on behalf of the turnpike authority, said the attachment bolt design was fairly standard. he said holes were drilled in the tunnel's concrete ceiling and then bolts were inserted along with a pressure-injected epoxy packing."
now why hire a geotechnical engineer to study a structural failure?
all those politicians demanding accountability are probably the same ones that look down their nose at structural engineers and sniff, "you guys are so conservative."

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