Degradation Mechanisms of a Lime-Treated Clay Induced by Wetting and Drying Cycles

Abstract The present experimental study is focused on analyzing the degradation processes of the mechanical performances of a lime-stabilized expansive clay exposed to wetting/drying cycles of various amplitude. Fully cured specimens were exposed to several wetting and drying cycles with suction-controlled techniques, and the maximum suction applied during the cycles ranged from 0.30 MPa to 95 MPa. The compressibility of the soil was determined through oedometer tests. Structural modifications at the micro-scale were evaluated through mercury intrusion porosimetry tests (MIP) and scanning electron microscopy (SEM). This study highlighted that the main deterioration mechanism of lime-treated expansive soils exposed to cyclic wetting and drying is a consequence of micro-structural changes whose intensity were controlled by the amplitude of the cycles.