Soil stabilization

About: Soil stabilization is a research topic. Over the lifetime, 3161 publications have been published within this topic receiving 48437 citations.

Sulfate Induced Heave in Oklahoma Soils due to Lime Stabilization

Abstract: Sulfate-induced heave in lime-stabilized soils is a serious problem that can cause costly infrastructure damage if not addressed and occurs when lime is added to soil containing sulfate. Lime, a common soil stabilizer, is mixed with expansive soils to make them non-expansive. However, when a certain amount of sulfate is present naturally in the soil, in the form of gypsum (CaSO 4 ⋅2H 2 O), the addition of lime (CaO) and water (H 2 O) will form a highly expansive mineral, ettringite (Ca 6 Al 2 (SO 4 ) 3 (OH) 12 ⋅26H 2 O) and cause excessive swelling. When exposed to water, ettringite can expand up to 250% and the resulting lime/soil mixture becomes more expansive than the natural soil; affecting and often destroying infrastructure. The purpose of this research was to determine a threshold level of sulfate in Oklahoma soils, above which adverse reactions occur as a result of lime stabilization. The volume change behavior of three natural Oklahoma soil samples, with and without a lime additive, was analyzed with free swell tests and a parallel gypsum solubility study on manufactured soils was performed. The preliminary data shows that the level of sulfates at which adverse reactions occur with the addition of lime in Oklahoma soils lies between 200 ppm and 8500 ppm, and researchers are continuing work to narrow this range. The results of the gypsum solubility study with manufactured soils have led to a faster and more comprehensive method for measuring sulfate content in natural soils.

Fly ash design manual for road and site applications

Abstract: This design manual describes the use of fly ash as a construction material for use as structural and nonstructural fills, backfills, embankments, base courses, roller compacted concrete dams and pavements, soil stabilization, land reclamation and other high volume uses. The manual details the physical, engineering, and chemical properties of bituminous, subbituminous and lignite fly ash. Included are field and laboratory testing methods, design data, procedures and examples, specifications, quality control, and pre- and post-construction monitoring. Volume 1 describes uses where fly ash is used dry or conditioned with small amounts of moisture. Volume 2 describes uses where fly ash is placed as a slurry with relatively large amounts of water.

Impact of Biocompatible Nanosilica on Green Stabilization of Subgrade Soil.

Abstract: This study reports the synthesis and potential application of biocompatible silica nanoparticles for subgrade soil stabilization. Nanosilica preparation as a major component from wheat husk ash is systematically studied and confirmed by FTIR, ICP, XRD, and TEM analyses. The produced biogenic nanosilica showed an amorphous structure with an average size of 20 nm. Upon loading various green nanosilica contents, our results show an improvement in the key parameters including Atterberg’s limits, maximum dry density, optimum water content, and shear strength of treated soil. Under optimal loading condition, the nanosilica-mediated soil analyses reveal a significant increase in the plastic and liquid limits by factors of 1.60 and 1.24 whereas plasticity index is declined by a factor of 0.78 rather than untreated soil specimen. The treated soil demonstrates a superior increase in the angle of internal friction, cohesion, shear strength, and maximum dry unit weight by factors of 2.17, 3.07, 2.21 and 1.5, respectively. The California Bearing Ratio (CBR) strength of nanosilica-cured soil presents a substantial increase by a factor of 5.83 higher than the corresponding original subgrade soil. We obtained the maximum increase in strength parameters of modified soil at the optimum biogenic nanosilica content of 1.5%.

Soil Improvement : A Ten Year Update

Abstract: Since the publication of Soil Improvement—History, Capabilities and Outlook after the Annual ASCE convention in Philadelphia in 1976, a dramatic growth in certain soil improvement techniques has occurred. The proceedings of the Symposium sponsored by the Placement and Improvement of Soils Committee, Geotechnical Engineering Division, ASCE at the 1987 spring convention is a ten year update that reports on major developments in the following areas of soil improvement: in situ reinforcement, densification, reinforcement of constructed earth, and chemical admixtures. The book includes four committee reports which are complimented by ten case history papers in the area of soil improvement that have occurred in the past decade. The case histories include the ground modification and construction test program at Steel Creek Dam to prevent liquefaction; the wick drain experiences of Caltran; the soil densification program at the Trident site in Georgia; the West Pinopolis compaction grout test program; slope effects when densifying sands; case histories of root piles, soil nailing, welded wire wall performance, and a reinforced polymer sea wall.