Deformation of unsaturated collapsible soils under suction control

Abstract Collapsible soils present significant geotechnical and structural engineering challenges worldwide. They can be found in arid or semi-arid regions are directly affected by the multi-step wetting procedure due to reduction of soil suction. The main objectives this paper investigate volume change behaviour, collapse mechanism deformation characteristics under control suction net vertical stress. In study, three types collapsible were investigated such as natural sandy gypseous, silty loess, artificial gypsum–sand mixture. A series constant stress-suction (wetting drying) tests using a combination axis-translation vapor equilibrium techniques deployed cover wide range applied test results show that large occur upon stepwise decrease. On other hand, shrinkage behaviour resulting from increases imposed is observed during drying path. depends on stress path function normal stress, suction, dry density, degree saturation. water content saturation dramatically increase decreases initial high zero values at