Abstract
Lime and cement are widely used in stabilization and improvement of the expansive subsoils that support pavement infrastructure. In this research, an attempt is made to stabilize a highly expansive soil rich with smectite minerals with an aim to understand the mechanisms that result in soil property improvements. Influences of both the type of stabilizer and their dosages were studied for modifying expansive clay from the north-central region of Saudi Arabia. Al-Qatif soil is known for its highly expansive nature, and it is known to induce major damage to low-volume roads built on untreated to unbound sandy bases. This research was performed by first characterizing and classifying Al-Qatif clayey soil by means of routine index properties, X-ray diffraction studies, and swell and shrinkage tests. Next, lime and cement were used to stabilize control clayey soils, and the treated soils were then subjected to the same soil tests. Effects of lime and cement treatments on Atterberg limits, swell, and linear shrinkage strain properties are addressed. Major conclusions and findings from experimental investigations are presented.