Soil Improvement by Jet Grouting

Jet grouting is a method for improving of soil properties and its physical characteristics. However, in this method due to high pressure and velocity of cement slurry the soil structure has been damaged as some parts are moved from the borehole replacing with cement slurry. The grains, which are remained in the borehole, mixed with slurry (cement) and create an improved mass of soil. This mass is named “Soilcrete”. Soilcrete mass has special characteristics such as high strength, low deformability and very low permeability. In this paper, principles governing to jet grouting and effective parameters have been explained. Then the test results obtained from Soilcrete column have been analyzed and discussed. Based on the results, jet grouting has led to increase and improvement of physical and mechanical characteristics of soils, i.e. uniaxial compressive strength, cohesion and internal friction angle. Finally the values of jet grouting parameters are recommended in order to achieve larger diameters in the mentioned site based on trial grouting results.