Alaska Highway Retaining Wall
Con-Tech Systems Ltd. supplied 72 permanent ground anchors for two walls along Richardson Highway about 60 miles south of Fairbanks, Alaska. The section of the road had been plagued by a slow moving landslide, which made it a high maintenance site for Alaska Department of Transportation.
As a solution, Malcolm Drilling and Wilder Construction designed and built two walls, one above and one below the highway. The upper wall had 37 15-strand anchors 100 feet in length; the remainder on the lower wall was comprised of five-strand anchors in four rows. All of the anchors were drilled through highly variable landslide debris and anchored to competent bedrock.
After the work was completed, Alaska had a series of earthquakes (6.8 and 7.9 magnitude) that originated near the job site. The anchors performed beyond expectation and the only damage observed was minor cracking of the cosmetic shotcrete facing on the upper wall.
At a Glance
Project: Richardson Highway
Owner: Alaska Department of Transportation
Details: 37 15-strand permanent ground anchors in upper retaining wall; 34 5-strand anchors in Iower retaining wall