| Jet Grouting |
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Jet grouting is an in-situ construction technique used to improve the mechanical characteristics of a soil. The technique is used in situations where increased stability and bearing capacity or decreased permeability is required. Because of its design flexibility, jet grouting is an important alternative to more traditional grouting methods, slurry walls, mechanical underpinning systems, micropiles, or ground freezing. The desired bearing capacity and permeability are pre-determined which determine the grout makeup and zone of treatment. High pressure is applied forcing neat cement or cement/bentonite stabilizer through a rotating jetting nozzle. As the nozzle is raised, the stream of grout destroys the soil matrix and creates a column of soil and cement. The jetting parameters of flow rate, pressure, retraction rate and rotation speed are determined by the energy required to create the column with the desired properties, and are closely controlled. An electronic recorder documents information for each hole. The Compu-Grout System, a real time integrated process to control and monitor the operation is also available. The Judy Company offers single and double fluid grouting: Single Fluid: A stabilizer fluid, usually neat cement or cement/ bentonite, is injected into the in-situ soil at high pressure and velocity, producing a homogeneous, high-strength column. In Granular Column diam: 2'-3' soilcrete strength 1000-3000 psi In Clay Column diam: 2'-3' soilcrete strength 250-1000 psi Double Fluid: compressed air is injected through its own nozzle simultaneous with the neat cement spray but with the cement sprayed at a lower pressure than with the Single Fluid method, allowing larger diameter, in-situ columns to be created. In Granular Column diam.: 3'-6' soilcrete strength 500-2000 psi In Clay Column diam.: 3'-5' soilcrete strength 150-1000 psi Advantages
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