GROUND IMPROVEMENT

Compaction Grouting, also known as Low Mobility Grouting (LMG), uses volumetric displacement to improve in-situ soil conditions. A very low slump grout (usually 0” to 3” slump at the point of injection) is pumped in stages to displace the surrounding soil. Compaction grout is typically comprised of a blend of sand, cement, gravel and water. Ground improvement can be achieved by staging or sequencing the compaction grout locations. In some cases, primary, secondary, tertiary and even quaternary treatment locations may be considered to maximize the effectiveness of the compaction grouting program. Compaction grouting is also an excellent alternative for re-leveling structures, reinforcement of fine-grained soils and void filling. Compaction grout mix designs can be altered to provide a wide range of unconfined compressive strengths depending on the requirement of the project. 

Chemical Grouting or Permeation Grouting refers to the use of certain chemicals such as polyurethanes, acrylates, acrylamides or sodium silicates for structural improvement or seepage control. The appropriate chemical grout can produce excellent results in a variety of applications. Careful consideration must be given to the selection of the grout and the contractor selected to perform the work to maximize the benefit of the chemical grouting operation. Chemical grouts have been successfully utilized to completely permeate clean sands to fill voids within the treated profile. Hydro-active grouts are commonly used to minimize or completely stop seepage in and around existing structures.

Slurry Grouting or Cement Grouting is the general terminology applied to placement of a cementitious binder such as cement, fly ash or slag in a slurry form (typically binder and water only). Slurry grout can be placed under pressure (Pressure Grouting), gravity filling, or tremie placement depending on the application and requirements of the project. Slurry grouting is most commonly used in the industry to fill cracks and voids in rock formations to create a water cut-off or to increase capacity. Slurry grouting is also commonly used for placement of grout in soil nail, micropile and anchor applications. Slurry grouts are also used to fill voids directly beneath existing foundations to reestablish intimate contact with the subgrade (Contact Grouting). As with most grouting technologies, the type of binder and water to cement (w:c) ratio will determine the strength of the material after fully curing. Additives can be used to engineer the appropriate slurry for the applicationDon’t cry because it’s over, smile because it happened.