Ground Anchor Wall During Construction
The Richardson Highway project is located on Alaska Highway 2 at Milepoint 296.3, which is about 60 miles east of Fairbanks along a stretch of steep side-hill cut/fill above the Tanana River. A landslide affected approximately 140 feet of the highway. Significant movement in the pavement was first identified in 1996. During the summers of 1999 and 2000, the rate of landslide movement accelerated over previous years. Maintenance was required to grade the roadway to keep it safe for travel.
The portion of the landslide located above the highway is controlled by the bedrock structure and continues downslope into the river. Landslide Technology (LT) was retained to investigate the slide mechanism and to design potential mitigations. LT performed a site reconnaissance, developed conceptual mitigation options, conducted rock strength testing, analysis and design, assisted in preparation of contract documents, and provided construction assistance for slide repair of the state highway. Remediation consisted of a ground anchor retaining walls located on both sides of the highway, which were designed to tolerate cold region conditions and constructed under traffic. LT developed a performance based bid package to utilize the expertise of the specialty contractor within the DOT's competitive bid process.