City officials and residents in Amsterdam, Netherlands are looking at the recent Cologne tunnel collapse and wondering if the construction of their fourth metro line could have similar problems. Although the tunnels themselves have not started construction, the future stations have. Some houses on the Vijzelgracht have experienced deformations related to the construction. (Right, a resident who used to live on the Vijzelgracht stands in front of buildings now uninhabited after experiencing settlement related to the construction of the metro stations. Photo Maurice Boyer, nrc.nl). From the NRC.nl article:
Twice last year a leak in the concrete wall of the underground station under construction there allowed water and sand to flow into the construction pit, damaging the foundations of adjacent buildings. Neighbouring houses sank up to 23 centimetres deep and have since been declared unfit for habitation.
The article goes on to talk about all of the schedule and cost overruns associated with the project and a few paragraphs comparing and contrasting the soil conditions and typical building foundations in Cologne and Amsteram. But I had to mention the photo at the top of the article. The mayor of Amsterdam and former executive for transportation are showing the route for the proposed “North-South line” of their metro system on a “globe of Amsterdam”. Hmm…someone is going to have to explain that one to me! (Photo by Vincent Mentzel, NRC.nl) Story from ASCE SmartBrief.