Wet spots have been detected along a portion of a new levee being constructed by a US Army Corps of Engineers Contractor. The levee is approximately 95% complete, but the Levee Board wants to establish what is causing the apparent seepage before accepting the levee. More after the break. (Photo of Katrina levee failure from greenmannowar)
Geotechnical drilling was set to begin yesterday on the 710 Tunnel Technical Study in the L.A. area. Currently the 710 freeway ends along the city of Los Angeles-Alhambra boundary but was intended to run north […]
The Claremont tunnel beneath the Berkeley Hills on the east side of Oakland is a water supply tunnel that serves over 800,000 customers in Richmond, Oakland, San Leandro and neighboring communities. One of the unique things about the tunnel is that it crosses the active Hayward Fault. Most of the time when you talk about designing for earthquakes youâ€™re talking about designing to withstand the seismic forces. In this case, the designers needed the water transmission tunnel to withstand up to 7.5-ft of offset due to fault slip and still maintain a minimum level of service. (Photo credit: Sue Bednarz, Jacobs Associates, Inc. by way of Civil Engineering Magazine)
This post describes the relatively recent Claremont Tunnel Seismic Upgrade Project as reported in Civil Engineering Magazine (May 2008, v. 78, no. 5, pp 58-63, 96-97).
I had an earthquake engineering course in my geological engineering undergraduate program, and an excellent teacher, but man, the math gave me fits! Well, apparently my time has finally come to make the effort to understand it again. A retired Canadian geophysicist/engineer is writing a series of articles on seismic analysis. Read more… (Photo by trochee)
The Kansas Geological Survey has some interesting seismic equipment that they have used on behalf of the U.S. Department of Homeland Security to look for drug tunnels along the US-Mexico border. I’ve never seen anything quite like this. The sensors all appear to be placed within an old fire hose and mounted onto a Bobcat Toolcat utility machine. On the front of the vehicle is a cyllinder with a 60-lb weight that gets dropped. Read on. (Photo by Richard Gwin, LJWorld.com)