Evaluation of Collapse Potential Investigated from Different Collapsible Soils
Collapsible soils are considered as one of the problematic soils, and widely distributed in North America, Europe, Russia and Asia. They show low dry density and moisture content in all testing schedule due to presence of cementation bonds or loess structure especially at unsaturated state in arid or semi-arid regions. Moreover large deformation, rapid settlement and high decrease in void ratio of a meta-stable soil structure occurred during wetting and loading. Two types of unsaturated collapsible soils are used in this study from different area in the world. Collapse potential(Ic) and collapse index (Ie) magnitude are determined according ASTM (D5333-03) by using the conventional Oedometer device in a constant temperature and humidity environmental at different stress level. It was noted that the value of collapse potential (Ic) affected by the rate of secondary consolidation (Creep) and time of wetting. It shows high values when flooding the specimens by water during primary consolidation. It is concluded that there is an increases in collapsibility due to removal of bonding between cementing particles upon wetting due to stress release and leaching of soil during water infiltration leading to softening due to rearrangement of soil particles.
KeywordsVoid Ratio Vertical Stress Loess Soil Collapse Potential Gypsum Content
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