5 May 2009
Nailing Jell-o to a wall…
Posted by Dave Petley
This is a guest post from Bill Rabenaldt from California about a novel soil nail mitifation technique.
Can you nail jell-o to a wall? Not easily. Can you nail a landslide area, levee or bluff before it fails? You bet!
The valley floors around Aspen, Telluride and other resort areas in the Rockies are all but built out. Where do business and families go? The surrounding hills and mountain sides are all that is available. I’ve seen pictures of several of these homes and they are spectacular. Generally, the home theaters and pools are built into the mountain side due to local height restrictions.
How are they doing it?
For the past 10 years, I have been a member of the Pismo Beach City Council. Our community is on the Central Coast of California half way between San Francisco and Los Angeles, just north of Santa Barbara. During that time, I’ve learned a lot. As an example, our bluff has eroded faster than expected in some areas and we are in immediate danger of losing our highway, force mains and our underground utilities. Pebble Beach was another coastal community that was in danger of having their main arterial fall into the ocean. Trying to figure out how we can overcome these natural and man-made disasters has been my personal and political motivation for many years.
There are also the devastating fires we’ve had around the world. Rains are causing landslides of varying proportion. Our once stable private and public property is now vulnerable to the forces of nature. Our levee system is old and decaying.
There is a company I’ve been following for about 7 years. I first met them at the League of California Cities meeting in Sacramento. Soil Nail Launcher had a booth at the event and I was interested in how an 8 foot nail could be driven into an embankment. Over the years, I understand they have driven many nails and have protected a whole lot of property. Not only that, they have done it for less than half the cost of traditional methods.
Here is a short story you will enjoy:
In WW2, Great Britain developed a gas canister launcher to stop the enemy’s progress. A canister could be launched as far as 3 miles away. Several years ago, a company bought this equipment and all the patents and converted it to a “soil nail launcher”. 2,500 psi is built up in a chamber and launches a nail at 220 mph into the unstable soil. These nails are typically between 12 and 20 feet long with a Super Launcher that penetrates up to 80 feet. The area is then left to nature or a shotcrete surface can be applied.
If you would like to see what intrigued me the most, go to their website: www.landslidesolutions.com to see what they have accomplished. Their services are averaging half of the cost of traditional “fixes”, they were approved by the California Coastal Commission, they have recently received a GSA (General Services Administration) contract number from the Federal Government for emergency services. They can solve geotechnical, construction and public safety problems.
A recent report by the geological society on the new faults found along the infamous San Andreas Fault causes serious doubt as to the earlier government findings of “acceptable standards” for construction, land use issues, and a host of other many other conclusions that must be reviewed. Many may need to be reconsidered and/or revised with this new information. Reinforcement may be the only logical solution.