Jet Grouting and Jet Mixing Techniques

Jet grouting, also sometimes referred to as jet mixing, is a method of grouting that uses very high pressure streams (6,000 psi or 40 MPa) of grout to erode, replace, mix, and cement soils. Jet grout construction uses a rotating and rising drill rod with small nozzles that direct the grout horizontally to form columns of soilcrete or soil-cement. Typical column diameters are 2 to 6 ft. Jet grouting is the only type of grouting that is capable of treating all types of soils from clays to gravel. Jet grouting is also useful in grouting isolated zones of soil and for grouting around and below buried utilities.

Creating Soil-Concrete Columns Using Jet Grouting Technology

There are at least three of types of jet grouting, some of which use air and / or water with the high pressure grout stream to improve soil penetration and column diameters. The procedure that is common to all jet grouting types (including double fluid jet grouting and triple fluid jet grouting) involves first drilling to the plan depth using small diameter drill rods. Next, a large and powerful pump is connected to the drill rod, which pumps the high pressure jet grout through the drill rods and horizontally into the soil. The drill rods are slowly rotated and raised creating columns of soil-cement. The shape of the grouted zone can be changed by directing the grout in ways that create panels, floors, or other shapes.