Cefali& AssociatesContactSpecialty structural engineering
Soil nail walls for staged excavation and retaining work, with nail layouts and facing designed for the ground conditions and available space.
How it works
A soil-nail wall reinforces the ground behind a cut with closely spaced bars installed as excavation proceeds downward in lifts. A facing connects the exposed surface. Feasibility depends on the ground, excavation geometry, nail length, drainage requirements, and the ability to build and protect each stage.
This approach can be useful where a conventional wall would be difficult to build from the bottom up. It still needs room for nails behind the wall. Property boundaries, easements, foundations, or buried facilities may force a transition to a different system along the same face.
Site conditions
A soil nail wall can be built from the top down as the excavation gets deeper. Cefali & Associates evaluates the ground conditions, wall height, property limits, and installation access to determine whether soil nails fit the project and where another wall type may be needed.
Engineering services
Cefali can evaluate soil nails during early planning or develop a detailed wall design using the geotechnical recommendations, survey, and excavation plans. The work covers the nail layout and facing, including transitions where property or access limits require another wall system.
We agree the drawings, calculations, and support during construction with you in the proposal.
Design considerations
The proposed wall height and ground conditions affect the required nail layout. Property lines and buried structures can restrict the available length, while access has to allow each excavation stage, nail row, and facing section to be built.
For the difference between construction-stage support and a finished retaining wall, read the temporary and permanent wall guide.
In practice / Vista Monterey Soil Nails
At Vista Monterey in Corona, Cefali designed top-down retaining walls. The tallest soil nail section was 25 feet with five rows of nails limited by the property line. Soldier pile walls were used on either side where nail easements were not available.
See the Vista Monterey Soil Nails projectRelated project work
See the systems, site conditions, and construction details from these projects.
Before you begin
Soil nails reinforce the ground behind an exposed face as excavation proceeds in stages. Tiebacks anchor a shoring wall from behind it. Both need suitable ground and space behind the wall, but their wall details and construction sequence differ. The choice depends on the geotechnical recommendations, wall geometry, property rights, and construction access.
Yes. A boundary or access change can make nails impractical along part of a wall. Vista Monterey combined soil nails with soldier piles where easement limits changed.
Start with the geotechnical report, site and property survey, grading or excavation sections, nearby structure records, and any facing requirements.
That depends on the rights available for the site. Vista Monterey used soldier-pile walls on either side of the nailed section where nail easements were not permitted.
No. The intended service life and final condition must be established before the wall and its facing are designed. Drainage and appearance can matter for permanent walls.
Discuss your project
Send the drawings, reports, and site information you already have, along with your schedule and the work you need help with. You do not need a complete design package to get in touch.