Pittsburgh Area Has 49 Active Landslides
A 20 to 30-ft high retaining wall in a subdivision in San Antonio Texas failed on Sunday causing an evacuation of 80 homes. After an initial inspection, some 55 home-owners were allowed to return. The massive tension cracks that opened along the wall and behind it were 12-15-ft deep and 6-8-ft wide. Reportedly, the wall had problems even before the subdivision was even constructed. More after the break. (Photo by Jerry Lara – San Antonio Express-News)
Devil’s Slide is an infamous landslide along California’s Highway 1 or Pacific Coast Highway near Pacifica, just south of the San Francisco Bay area. Caltrans’ Devil’s Slide Tunnel project is an effort to bypass that slide and make the heavily traveled roadway safe for drivers and to eliminate the maintenance and traffic hassles caused by slope failures blocking the road. We first covered the project back in September of 2007 when the tunnel portion of the project commenced. In that post, you can find a Google Earth KML File showing the location of the tunnels and the new bridges associated with the project. In this post, I’ll provide you with some updated progress information as well as some background on the geotechnical and other aspects of the project. More links and videos are at the end of the post. (Photo by Kim Komenich, San Francisco Chronicle). […]
On March 21, 2008 a landslide caused the closure of Arizona State Route 87 between Payson and Phoenix near mile post 224. So far there are no official estimates as to the size, but based on aerial photos, it appears to be at least 50,000 sq-ft in plan. The offset at the head scarps was approximately 2-meters (6.6-ft) according to AZGS Geologists on site. It appears to have been a rotational slide as the toe of the landslide heaved the southbound roadway up by as much as 1-meter (3.3 ft). There was an existing soil-nail retaining wall on the slope that was destroyed by the slide as well. Lateral deformations can be seen in photos of the median barrier and the roadway striping. The deformations extended into the northbound lanes as well. More photos and links after the break. (Photo by ADOT)
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