There were three fairly recent rockfall events with fatalities that made the news and caught my eye. State Highway 36 in New Zealand is still closed after a major rockfall occurred in Rotura. The photo […]
In Sichuan Province, China, they were still in the recovery process from the devastating 2008 earthquake when a series of landslides, rockfall, mudslides and flooding has hit the region. Dave’s Landslide Blog has excellent coverage as usual on the slide pictured here, which blocked a major road, hindering rescue efforts. (Photo Xinhua/Jiang Hongjing)
A remarkable video of the aftermath of a bridge destroyed by one of these rockfall / landslide events is shown below. The destruction is pretty profound. (Via Geology.com)
Also on Dave’s blog, a landslide in Guangxi caused a train to derail, killing 4 people and injuring 50. My heart truly goes out to the people of those portions of China, particularly in Sichuan as they have been through so much.
The Devil’s Slide Tunnel project is on schedule and on budget according to a news story at ABC7News.com from earlier in June. The video (shown after the break) has a few nice shots showing rock bolting, soil nailing at the portals, and the geologic mapping and laser scanning that happens at the tunnel face.
I also came across a very neat article about how the Ocean Shore Railroad Company was the first to try to cut into the slope along what is now PCH 1 at the Devil’s Slide back in the early 1900s. They were trying to connect the then rural farming community of Half-Moon Bay with San Francisco. The railroad fought the reoccurring landslide and serious rockfalls. Ocean Shore Railroad went bankrupt in 1922 and pulled up its rails, making room for the current highway. (Photo at left from halfmoonbaymemories.com)
More videos! French Company G.T.S. has posted some great videos on rockfall protection systems on their YouTube channel. I don’t speak French, so I can’t give you any more info on the company (although their website looks like it has plenty of info!). But the videos cover the preparation of, drilling for, and installation or rockfall protection fences and barriers as well as a couple of general rockfall ones. They just have video with background music, so no worries about a language barrier. You can watch the installation video below.
The rock at left travelled nearly a mile down the slope and picked up some significant velocity before impacting a house, hitting the back wall and damaging the ceiling before dropping through the floor into the garage and damaging the garage door. In an often-overlook advantage of the current financial crisis, the house was currently in foreclosure and therefore not occupied at the time of the damage. Read on for links, more info and a map of the location so you can view the terrain. (Photo by Provo Fire Department by way of Utah Geologic Survey)
The Colorado Geologic Survey has a very comprehensive overview of the geologic hazard of rockfall in all its many forms in their latest issue of RockTalk newsletter. The entire 24-page newsletter is devoted to various aspects of the problem, mitigation options and case studies all with excellent photos. I highly recommend that you check it out. Click through for the link. (Photo by CGS)
Thank you to my old colleague at URS Corporation, Andy Messer for sending me a link to these videos. The are from an Austrian company, Trumer Schutzbauten, that provides products and research related to rockfall fences. The first video is presumably to show the hazards of camping next to hazardous rock slopes…good fun! Click through for the videos.
Geovert, a specialty design-build geotechnical contractor in New Zealand and Australia has released a video showing the construction of a challenging rockfall protection project. From their YouTube description:
Stockton Coal Mine is situated on the rugged west coast of New Zealand’s South Island, near Westport. Geovert, a design-build contractor specializing in difficult access rockfall mitigation projects, were retained to provide a turnkey solution combining slope protection and stabilisation measures, to manage the rockfall hazard and protect the surrounding environment with a world class design build rockfall protection solution. The barrier was 1.7 kilometres long and follows a ridgeline escarpment, making this the longest rockfall protection barrier in the southern hemisphere. This was one of the largest and most challenging rockfall construction projects completed to date anywhere in the world.
Click through to see the video.