ABSTRACT
Swell and shrinkage-related volume changes of unsaturated expansive soils cause severe distress to infrastructures. Recent research showed that polypropylene (PP) fibers could reduce volumetric shrinkage strains of expansive soils by 15% to 30%. It is assumed that the combined lime and fiber stabilization could reduce total volumetric movements of expansive soils and mitigate distress problems. The present research was conducted to address the effectiveness of combined quick lime and PP fiber stabilization to enhance swell, shrinkage, and strength properties of four expansive clayey soils. Fiber distributions in soil specimens and repeatability of test results were first addressed. Engineering test results showed considerable reductions in swell and shrinkage strains, and these reductions will lead to better treatments of expansive soils by controlling moisture movements through cracks. Test results indicated statistically significant improvements in the expansive soil properties, indicating the effectiveness of this treatment method. Contributions of lime and fibers to enhance soil properties were also addressed.
