Soil Nail Wall – How it Works

How It Works

Excavation:

Benches are cut in lifts of typically 4-6 feet.

Nails:

Holes are drilled into the excavated face. Each drill hole is filled with cement grout and a nail is inserted. The grout binds the nail to the surrounding soil and provides corrosion protection. A steel plate attached to the protruding end of each nail helps transfer forces from the wall to the nail and soil.

Drainage:

Horizontal and vertical drain strips are installed onto the face to eliminate hydrostatic pressure and control seepage.

Facing:

A facing, constructed from shotcrete reinforced by welded wire mesh or reinforcing bar mats, provides structural integrity.

The shotcrete can be smooth troweled for a finished appearance or sculptured for an architectural look to resemble the local geology.

Continuing Construction: After each lift is completed, excavation continues to the next bench and the process is repeated to completion.

Advantages of Soil Nailing:

  • With the right soil and website conditions, a rapid and economical means of constructing earth retention support systems and retaining walls.
  • Allows foundation construction in limited areas.
  • Works through different soil strata.
  • Constructed from the top down.
  • Shorter drill holes.
  • Smaller diameter bars at shorter lengths.
  • Retaining walls are secured laterally into the soil, eliminating piles and foundation footers.
  • Excavation for the building and wall construction can proceed simultaneously, saving schedule time.
  • Not prestressed, saving labor costs and time.
  • Grouting only once is required, saving time and labor.
  • Requires only cohesive soil or broken rock, does not need to be anchored in competent rock.
  • Drainage system included eliminates hydrostatic forces on facing.
  • Hard face shotcrete is applied and can be finish-troweled.
  • Forming and placing concrete wall not necessary, saving time, materials, labor.
  • Soft facing can be applied for soil retention or slope protection.

Is a Soil Nail Wall the Best Solution for Your Project?

We would invite you to contact us so that we may learn about your project.

More Reading:

Better Roads Publication – “Soil Nailing – DOTs Warm Up to New Technology”