Nicholson in the Neighborhood: Virginia's North Hill Project-Video

Video Transcription

Video Summary

Dominic Ammon of Nicholson Construction presented the North Hill Project, a 2020–2021 retaining-wall project near Alexandria, Virginia. The development transformed a long-abandoned, settling mobile-home site into space for multifamily housing, townhomes, and a park. Highly variable coastal-plain soils, groundwater, and potential slip surfaces posed major challenges, alongside restricted access, strict movement limits, and COVID-related constraints.<br /><br />The design used large-diameter drilled soldier piles, deep pile embedment, and multiple rows of ground anchors. Construction required adapting drilling methods as crews encountered perched water and running sands, including switching to segmental casing. Anchors were proof-tested, and reinforced shotcrete provided the finished wall face.<br /><br />Poor backfill and compaction initially caused excessive deflection in one section during anchor stressing. Work paused while the material was replaced and properly compacted; stressing then resumed. Final wall movement remained below half an inch, within the two-inch limit. The presentation also emphasized safe, engineered working platforms for heavy drilling equipment.

Keywords

retaining wall

ground anchors

soldier piles

soil stabilization

drilled foundations