Soil Modifications
Anchors
Anchors are used in rock formations or earthen formations to increase shear, tensile and load
bearing strength from slope failure. The more common areas for anchors are to secure retaining
walls, bulkheads and rock formations. A variety of anchors systems may be used. For example,
steel bars grouted into drilled holes or cable strains anchors (made up of cables wound together)
are common types of anchor systems. There are also anchors with designed drill bits for self
dri1ling were hole failure may occur during placement of tradition anchors.
Anchors are more substantial than sod nails. Anchors are used to brace retainirig walls,
bulkheads and rock faces. They may be steel bars or twisted cables grouted into boreholes,
or rods with rudimentary drill bits where the borehole may collapse during placement of a
traditional anchor. Some anchors may also use steel pipe to drain the interior of the rock mass.
Soil Stabilization
Chemical and cementitious grouts are used below grade for soil enhancement for repairs
such as building, bulkheads and open cuts pits/tanks. Soils can be modified to increase compaction,
tensile and shear strength. The injection of grouts to stabilize soil formations is very useful in
projects around waterways where forming and pouring concrete is not possible. Grouts vary in
performance from rigid, gel or elastomeric to allow for adhesion and cohesion capabilities.
Traditional applications are commonly used in open cuts for tanks, collection pits, building and bulkheads.
Soil Nails
Soil nails are steel rod or cable grouted in boreholes, anchoring potential slide masses. Short soil
nails may also be used to anchor shotcrete or reinforced gunnite walls.
For below grade structural repair in or around buildings, bulkheads, pits or tanks.
Grouts can increase compaction, tensile and shear strength. Injection of rigid, gel or
elastomeric grouts with adhesive and cohesive properties can allow excavation after soil stabilization.
Slurry walls/Trenches
Slurry was are used to control the lateral or vertical movement of gases or fluids in a
strata formation. Mixing bentonite (expansive clay) with cement and placing it in an excavated
cut controls fluids for a cut off wall. Use of a ploy liner in the open cut can also enhance performance.
Slurry walls are most appropriate when full penetration from surface is required in a groundwater
barrier. Expansive bentonite clay is mixed with soil or cement and emplaced in an excavated cut.
Poly liners (HDPE) can be placed in the cut to enhance it performance.
Subsurface Barriers
Applications for Subsurface Barriers can range from landfills, waste sites or migrations of
contaminates through soil formulations. Subsurface Barriers can be constructed from open cut slurry
walls, compaction, permeation or jet grouting. Where applications vary for choosing the most effective
method of containment or locking up is the permeability of the soil mass.