ABSTRACT
A comprehensive series of unconfined compression (UC), unconsolidated undrained (UU) triaxial, and resonant column (RC) tests were conducted on chemically stabilized specimens of sulfate-rich expansive clay from southeast Arlington, Texas, after being subjected to repeated wetting-drying (w-d) cycles artificially induced in the laboratory. Results were used to assess the influence of cyclic w-d on long-term strength, stiffness, and one-dimensional (1-D) swell-shrink response of treated soil, including unconfined compressive strength, undrained shear strength parameters, dynamic shear modulus, and material damping. Stabilization methods included sulfate-resistant type V cement, low-calcium class F fly ash, and quick lime mixed with polypropylene fibers. Treated soil specimens were cured for 7 days and then subjected to 0, 1, 2, 4, 8, 16, and 32 w-d cycles prior to UC, UU, and RC testing. A w-d cycle consisted of 12-h immersion in a potable-water bath at room temperature followed by 12-h drying in oven at 140 F. Custom made w-d chambers allow for the monitoring of 1-D swell-shrink response during repeated w-d. A 10%-by-weight dosage of type V cement appears to yield best overall performance under cyclic w-d.
