Jet grouting, despite the name is different from grouting. Jet grouting is a vital process in modern day construction for improving soil, helping lay a better foundation for buildings and improves the load bearing of the ground.
Jet grouting, despite the name is different from grouting. Jet grouting is a vital process in modern day construction for improving soil, helping lay a better foundation for buildings and improves the load bearing of the ground. The process uses high pressure fluids or binders (usually cement) at high velocity to break up, homogenize and bind together the soil below the surface. Once the soil is homogenized, the soil solidifies, creating a much more solid ground than before treatment. This ground improvement technique can be used in almost any soil type, making it an integral part of any foundation work. Here's how it works.
The Monofluid System
Though different jet grouting techniques vary slightly, they all work around the same principle. One method is called the "Monofluid" system. This system starts by boring a hole into the surface with a drill and high pressure air or water nozzles to break up and mix the soil around the drill. One the drill reaches the desired depth, the air and water is shut off and the grout is injected at high pressure into the hole through a nozzle on the drill. The grout mixes with the soil and binds it together, solidifying the soil, while the drill is slowly pulled out.
The Three and Two Fluid System
The "Three Fluid" jet grouting system is similar in its process, but varies after in how the binder is applied to the soil. Like the monofluid system, the ground is drilled, along with a flushing fluid to manipulate the soil. After the drill has reached its depth and before the binding agent is applied, air and water are injected through their respective nozzles to further break up soil and particles around the shaft. As the drill withdraws, the binder is injected into the soil. The air and water injected into the solid before the binder creates a lighter mix, and the air pressure and pumps excess soil and water out of the drill area. Though the 3 fluid system is slightly more complicated, there are a few advantages, one of them being that the radius of the grouted column is larger, therefore covering more area and reducing the amount of times contractors would have to drill for a single job. This makes jobs on ground that's harder to drill much easier.
The Two Fluid System uses the same technique of the Monolith System, except compressed air is used with the binder. Like The three fluid system, the two fluid system increases the area of ground covered, but doesn't require as much equipment.