Advantage Engineers provided geotechnical engineering and construction observation during reconstruction and stabilization of steep slope supporting a residence on the cliffs of Atlantic Highlands. A storm battered the local region with significant rainfall, which exacerbated existing instability in the embankment resulting in a significant slope failure and extensive debris field. The homeowner contacted Advantage to complete a geotechnical investigation of the slope failure and provide viable options to stabilize the embankment face and protect the home.
Based on the results of the subsurface investigation and engineering analysis of the geometry of the prior and failed conditions, Advantage developed a comprehensive strategy to stabilize the home and the hillside which included the use of soil nails and high-strength, steel mesh facing. Advantage drafted and modeled cross-sections through the embankment and provided detailed construction drawings and bid documents and aided in selection of a qualified specialty geotechnical contractor.
The slope was reconstructed by end dumping loads of new fill material to construct a compound slope with an inclination of approximately 1.5H:1V for the approximate upper 20 feet with the remainder of the embankment inclined at approximately 1H:1V. Construction included installation of several hundred soil nails and edge pins which were grouted in place with high-strength, cementitious grout. The surface of the new embankment was covered with robust erosion control fabric and ultimately tied together with high-strength, steel mesh facing to address both deep seated and veneer failure envelopes.
The undulating topography and difficult access presented significant construction challenges, but through the collaboration and creativity of the project team (Advantage, Owner, & Contractor) an exceptional end result was achieved.