Stabilization of Soft Soils by Soil Mixing

Abstract

The use of soil mixing for providing stabilization of soft or loose soils is considered a fairly new technology in the United States. Soil mixing has been successfully applied for liquifaction mitigation, steel reinforced retaining walls, groundwater cutoff walls, and stabilization of contaminated soils. Applications of this technology have recently been further expanded. Such applications have included settlement control of soils, slope stabilization and the formation of composite gravity structures. To design for these applications, the unconfined compressive strength, elastic modulus and shear strength of the soil and soil-cement columns must be determined or estimated. Settlement control of soft or loose soils under service loads can be sufficiently controlled with treatment ratios in the 20% to 35% range. On a recent project in Honolulu, Hawaii, loose soils were sufficiently stabilized with a 23% treatment ratio, and at a site in Lakeland, Florida, a very soft and compressible clay layer was sufficiently stabilized with only a 12% treatment ratio. In slope stability applications, soil mixing improves the overall shear strength of the soil formation to adequately increase the factor of safety, and also the soil-cement columns can force the potential failure surface deeper. Lastly, soil mixing has been applied to construct in-situ gravity structures where its composite action design assumption was confirmed with an instrumented test wall, and used in two recent commercial applications.

The Analysis of Geotechnical Properties of Soils improved by Different Nanomaterials

“…Some of the literary works that analyzes the soils with different techniques are reviewed here. Kenneth B. Andromalos et al [2] have discussed that the use of soil mixing for providing stabilization of soft or loose soils was considered a fairly new technology in the United States. Soil mixing has been successfully applied for liquefaction mitigation, steel reinforced retaining walls, groundwater cutoff walls, and stabilization of contaminated soils.…”

Engineering application of vacuum preloading combined with electroosmosis technique in excavation of soft soil on complex terrain

“…The former three methods are accomplished by pumping a cement-based grout into the soil or mixing with the soil forming soil-cement column. The use of cement-soil mixing piles for providing stability of soft or loose soils also has yet widely spread in the excavation site [ 15 ]. Hu [ 16 ] presented the application of cement-soil mix piles to a deep excavation in soft soils adjacent to the Shanghai Metro tunnels.…”

A testing procedure for predicting strength in artificially cemented soft soils

“…The strength of treated soft soils is in the order of 100 to 1000 kPa in terms of unconfined compressive strength (Terashi and Juran, 2000). This practice has been widely used, as described by Lin and Wong (1999), Andromalos et al (2001) and Hussin and Garbin (2012). The research group at Federal University of Rio Grande do Sul, Brazil (e.g., Thomé et al, 2005;Consoli et al, 2008Consoli et al, , 2009aConsoli et al, ,b,c, 2010Consoli et al, , 2011Consoli et al, , 2012Consoli et al, , 2013aConsoli et al, ,b, 2014aFestugato et al, 2013;Faro et al, 2015) has been studying key parameters dictating strength and stiffness of lime/cement treated soils.…”