The area is approximately 300-m from the Rhine River, and groundwater is very shallow. As noted in another NCE article, the contractor constructed 15 dewatering wells when only 4 were approved. Additionally, the pumping rate being used was 750 m^3/hr, or nearly double the 450 m^3/hr it was pumping in December of 2008. Clearly the groundwater is one component of the failure, but it does not appear that there is sufficient evidence to say exactly what role of the groundwater was or if the shoring walls did in fact fail and lead to the collapse of the Cologne historical archives and the deaths of two people.
Related Articles
Centennial of NY Grand Central Station…And What the Future Holds
New York’s famous transportation icon, Grand Central Station (more properly Grand Central Terminal) celebrated the 100th anniversary of it’s opening on February 2, 2013. This rail terminal is more than just a means of travelling from point A to B, but it is a romantic, and grandiose metaphor for the hustle and bustle of American life. While the structure is definitely a cultural and architectural monument, it is also an engineering marvel, a fact recognized in 2012 by ASCE when it named it a National Civil Engineering Historic Landmark.
While the centennial of the GCT is being celebrated, a new project is taking shape approximately 90 feet below the existing tracks. The East Side Access project (ESA) will provide a new connection from the Long Island Rail Road (LIRR) to GCT. This project will help…
[Editor] Click through for the rest of this article, including a list of some interesting websites on Grand Central Terminal and the East Side Access Project. [/Editor]
Tunnel Proposed to Link Europe and Africa at Straits of Gibraltar
The proposed railway tunnel will link Spain and Morroco underneath the Straits of Gibraltar. The depth of the straits ranges from 1,000-ft to nearly 3,000-ft. To put that in perspective, the English Channel is only 150-ft deep, and the Chunnel is another 130-ft below the sea floor. (Photo by chodaboy)
Feb. 7 Bertha update: Two factors contributed to tunnel stoppage
WSDOT released an update on February 7 with some conclusions regarding the blockage that has stopped the Alaska Way Viaduct Tunnel Boring Machine, Bertha’s progress since December 6. Now they don’t think it was necessarily the well casing after all.
They cite two factors that contributed to the blockage. First, the cutterhead was clogged with material. You can see an cool short video of a worker unclogging the cutterhead. Not terribly dramatic, but still cool. The second factor was increased temperatures inside the equipment. STP discovered damage to a seal that protects the machine’s main bearing. They are still determining how the repairs will be done.
If you want to follow the chronology of this issue, read below for summaries and links to previous updates from WSDOT. And Check out the videos too! [Source: WSDOT]