Soil Nails

Soil Nailing is a technique used to reinforce and strengthen existing ground to stabilize slopes and excavations this process is highly recommended for cohesive soil, broken rocks, shale conditions. It consists of installing closely spaced bars, and placing a front spaced support into a slope or excavation as construction proceeds from top to bottom. And later grouted if installed in drilled holes. Not grouted Soil Nails are also possible if driven on grounds. It is a way of constructing retaining wall for excavation support, hill cuts, bridge abutments and roadways

1. Excavate soil cut

2. Drilling of nail holes

3. Install soil nails and grout

4. Shotcrete installation for soil surface (optional)

5. Construction from top-bottom sequence

6. Provide final facing for aesthetic

Soil Nailing has many advantages compared to any other ground improvement techniques. Some of this advantages are enumerated below:

• It can manage to work for a less space area.

• Less Disruptive

• Less damage on other structures within the vicinity

• Minimum shoring

• More cost efficient

• Can be used for temporary constructions

• Reduced inconvenience such as road traffic

Some of the disadvantages of soil nails are:

• Soil nails are not applicable for large amount of groundwater seeps on excavation.

• Permanent long term applications are not recommended.

• Sand and gravels are not compatible on this process.

• Not practical to use on areas with a high water table.

Soil nailing used materials such as reinforcing bars and grout installed with an inclination of 10 to 20 degrees to the vertical. Here are some commonly used soil nail process:

• Drilled and grouted soil nailing method

• Wherein holes are drilled on a slope surface then nails with a diameter of 100-200mm spaced 1.5 meters on center are inserted on holes with grout.

• Driven Soil Nailing Method

• Commonly used for temporary stabilization, it is fast. however, it does not provide corrosion protection to the steel or nails. Diameter of nails are around 19mm to 25mm spaced at 1 meter on centers.

• Drilling Soil Nailing Method

• Hollow bars are used in this method, bars are drilled and grout is injected, typically faster than driven nails.

• Jet Grouted Soil Nailing Method

• It is used for eroding soil for creating holes in the soil surface, steel bars are installed in this hole and grout with concrete.

• Launched Soil Nailing Method

• In this method soil nailing steel bars are forced to the soil with a single shot using compression by an air mechanism. It is fast. Good on sliding soil conditions. Soil Nail diameter is 38mm and its length around 6m.

• Soil nails must penetrate beyond the slip plane, the spacing of soil nails on grid pattern must be related to the soil strength and bearing capacity. The construction must be monolithic any delay may cause danger on slope stabilization.

Contact the specialists at Geo Grout Ground Modification Specialist Inc. of Western United States for your chemical grouting project needs. Call us at (650) 241-2400 for complete information on our Soil Nailing services or email us at inquiries@gggms.com to discuss your Soil Nailing needs today.