Restoring RW5 at Yeager Airport: Design and Construction of a Tall Retaining Wall on the Side of a Mountain

On March 12, 2015, the runway safety area (RSA) and engineered material arresting system (EMAS) were destroyed when the 73-m (240-ft) high reinforced earth slope failed at Yeager Airport in Charleston, West Virginia. The cleanup and stabilization of the area resulted in the displacement of the Runway 5 threshold and the shortening of the usable length of Runway 5-23. This impacted airline as well as Air National Guard operations. Thus, it was critical to restore safety features and normal operations as quickly as possible once the debris was removed, leaving a temporary 1.5:1 slope. To achieve this goal, a new 122-m (400-ft) long retaining wall up to 25-m (83-ft) high was designed and constructed to meet the difficult site conditions and restore safety features of the runway. To control load magnitudes as well as to facilitate construction, the wall was designed with two distinct sections. The lower portion of the wall was designed to retain compacted soil backfill and be secured to the existing sandstone bedrock with rock socketed steel piles and post-tensioned tieback anchors. This soil backfill establishes a stable 2:1 (horizontal:vertical) slope in the area. The upper portion of the wall was backfilled with up to 17 m (55 ft) of geofoam with a steel post and concrete panel facing. This paper will present an overview of the design and construction challenges posed by the site conditions as well as those associated with bottom-up construction of an anchored soldier pile wall and incorporation of geofoam backfill. Construction was ongoing at the time this paper was completed.