Soil mixing is a construction technique that introduces an engineered grout or other reagent into the ground to modify the physical or chemical characteristics of soil without the need for excavation of the contaminated materials. The intent of soil mixing is to modify the soil so that its properties become similar to that of a soft rock (like clay, shale, or lightly cemented sandstone).
This technique has numerous civil and environmental applications and can use a wide range of soil mixing equipment. RECON uses special mixing tools customized to meet the needs required of each projects contaminated soils. Soil mixing is commonly used as a stabilization or in-situ fixation method for building and bridge foundations, retaining structures, liquefaction mitigation, temporary support of excavation and water control, and containing hazardous wastes and sludges. Two common types of soil mixing that RECON is capable of includes wet soil mixing and dry soil mixing.
Wet soil mixing and dry soil mixing are both in-situ techniques that improve the characteristics of weak soils by mechanically mixing them with cementious binder slurry to form underground columns. To construct the columns, a drill advances a hollow drill steel with mixing paddles located near the bottom of the drill into the ground. The binder is then pumped through the hollow drill steel as it is removed from the ground. The radial mixing paddles allow for additional soil mixing as the tool is removed. The process then repeats next to the constructed columns, thus creating individual soilcrete columns that overlap.
Wet soil mixing is typically best for soils that have a moisture content of roughly 60 percent.
Dry soil mixing is typically best for soils that have a moisture content that is greater than 60 percent.