Investigation of the Mineral Dissolution Rate and Strength Development in Stabilized Soils Using Quantitative X-Ray Diffraction

Abstract

AbstractThe design of chemical stabilization of clay soils typically relies on empirical studies that utilize 28-day strength, measured as unconfined compressive strength (UCS) or California Bearing Ratio (CBR), as the design criterion. At present, it is generally not possible to extrapolate the results of individual studies to other soils, mainly because there is no quantitative understanding of the chemical reactions that cause strength increase over time. Accordingly, the objective of this study was to investigate whether quantitative X-ray diffraction (QXRD) can be used to establish a quantitative relationship between the mineralogical (microscopic) and strength (macroscopic) properties of kaolinite clay stabilized lime, portland cement, and Class C fly ash. The UCS was observed to change linearly with dry unit weight and logarithmically with time up to 300 days of curing. The kaolinite content in the stabilized samples also decreased logarithmically with time, accompanied by a concomitant increase in...