We have discussed about soilcrete columns in previous posts. In this post we will learn about deep soil mixing technique for constructing soilcrete structural elements. This is a method of injecting cement slurry named grout to required depth to stabilize foundation soil to have better engineering properties of soil.
A mixing tool is used to blend soil with grout. The mixing tool is hollow to facilitate grout to inject through it. In this method of mixing, the tools used for mixing consists of cutters or blades and paddles. The all elements are designed and arranged to facilitate mixing and agitation of soil-cement slurry to construct columns of soilcrete of diameter ranging from (3-8) ft. the resulting columns rendered a compressive strength of the order of (200-600)psi.
If the existing soil is saturated, sometimes cement can be injected as powder. There a insitu hydration of cement is occurred. The dry powder injection in this method serves the purposes as that of cement slurry injection.
Either powder or slurry injection render a stabilized soil mass of increased bearing capacity, less settlement susceptibility. Thus the stabilization options mitigate earthquake liquefaction hazards that are very frequent in soft soils. This method is especially suitable for treating foundation soil that have to support a structure having large footprints like slab foundation or storage tank.