A nifty BIM-type view of the proposed bored tunnel for Washington SR 99, the tunnel to replace the aging Alaskan Way Viaduct along Seattle’s waterfront. It’s pretty neat to see the piles and foundations for other structures and major utilities as the bore passes by them. A little on the longer size, at around 5 minutes.
Failures
Pile load test accident, dead load topples into street (Video)
A pile static load test went awry in Singapore when a pyramid of dozens of concrete blocks used for the reaction force toppled over into Gilstead Road. The force of the collapse caused a gas main to rupture but there were no reports of injuries. Click through for the video.
Geologic Hazards
ASCE: Cease and Desist over Video Spoof
The American Society of Civil Engineers ASCE sent a cease and desist letter to the owner of the Levees.Org website notifying them to remove a video spoof of its post-Katrina levee inspection. Of course, through the wonders of the internet, Levees.org removed it from YouTube, but someone else posted it again. And because of all the fuss, it’s more popular than it would have been otherwise with over 16,000 views at the time of this post. Click through to watch it.
Failures
Cologne Tunnel Collapse: Investigations Focus on Tiebacks and Groundwater
The latest information to come out of the collapse of a subway tunnel excavation in Cologne, Germany is that investigators are evaluating the ground anchors or tiebacks that were holding open the subway tunnel excavation. There doesn’t appear to be much information available to the public yet, and the New Civil Engineer article mostly quoted academics saying an anchor failure “could” have caused the collapse. Apparently at the time of the collapse, the excavation had reached the bottom depth after the slurry walls had been constructed along with the ground anchor system. Crews were supposedly working on the base slab which would have undoubtedly stiffened up the whole system. For what its worth, an anonymous comment left at the bottom of that article indicated that after half of the debris had been excavated, the diaphragm walls were still intact and without apparent displacement. So what other theories have been floated? Read on for more info. (Image Credit: New Civil Engineer)