Soil & Rock Anchors

Soil and rock anchors are typically pre-stressed bar or multi-strand tendons that carry vertical and lateral earth pressures and uplift forces. Temporary tieback anchors are frequently installed with conventional excavation support systems. Permanent tiebacks are used for permanent earth retention and marine bulkheads. Permanent tiebacks or vertical tiedown anchors are also used to increase dam stability to meet seismic codes.

The basic components of an installed anchor element are the pre-stressing tendon, either bar or strand and with a pre-defined unbonded (free) length and bond length; a bearing plate with trumpet; an anchor head; and the anchor grout. Load transfer to the soil or rock is achieved by the grout-to-ground bond stress.

Anchors can be installed by gravity grouting, pressure grouting or by using a post-grouting (re-grouting) technique. The proper installation method is determined based on the soil/rock conditions at the site. In aggressive soils, permanent rock and soil anchors may be corrosion-protected for longer service life.


  • Lateral reinforcement of temporary excavation support (sheet piling, soldier beams and lagging, secant pile walls)
  • Lateral reinforcement of permanent retaining walls
  • Lateral reinforcement of marine bulkheads
  • Slope and landslide stabilization
  • Slab and foundation tiedown for resistance to vertical uplift and overturning
  • Seismic upgrade structures and of dams

Advantages & Limitations

  • Can provide extremely large load capacity depending on anchor size
  • Can be installed in both soil and hard rock conditions
  • Can be installed through cobble and boulders
  • Permanent underground easement may be required
  • Underground utilities may prohibit the use of anchors

Moretrench's experienced team of professional engineers can assist in determining the proper anchor requirements to meet your project needs. Read more about Moretrench’s anchor experience: Emlenton Retaining Wall, Heinz Wall and West End Residences.