Rehabilitation of Medium Expansive Soil Using Cement Treatment

Problematic soils such as swelling/shrinking soil are widespread in the Middle East and worldwide. This type of soil, upon wetting and drying, causes severe damage to structures built on such soil. Rehabilitation of swelling/shrinkage using cement treatment was studied in this work. Medium expansive soil (12 PI 24) was selected for the present investigation. Soil specimens were mixed with various percentages of cement contents (1%, 2%, 3% and 4%) and molded to a range of prescribed pre-wetting dry densities and moisture contents. It was found that 2% cement content cured for 28 days was sufficient to reduce the free swell percentage for medium expansive soil from as high as 7.4% to merely 0.4%. The potential swell pressure, however, was reduced from a damagingly high value (333 kPa) for the untreated soil to a tolerable value (20 kPa) for the same enhancement conditions. Swell potential versus time relationship for the natural and stabilized soil could be very accurately represented by a rectangular hyperbolic function.