Consolidation Behavior of Structured Clayey Soils: A Case Study on Shiraz Fine Alluvial Strata

摘要

Owing to bond structure forming through depositional history and aging, natural sedimentary soils behave differently, in comparison to their reconstituted/destructured counterparts. Herein, consolidation behaviors of high-quality undisturbed and completely reconstituted samples of a fine alluvial clayey soil from Shiraz are studied. Experimental findings elucidate the impact of bond structure on virgin oedometric consolidation of undisturbed clayey samples, in so far as void ratio for such soils experiences insignificant change at vertical effective stresses lower than yield stress (about 105kPa). Nevertheless, beyond the yield stress, structured specimens exhibit a rapid change in void ratio with vertical effective stress, in comparison to that of the completely reconstituted ones. Finally, with extensive bonding destructuration under elevated normal effective stress, disparity between normal consolidation curves of initially structured and fully reconstituted specimens becomes negligible. It is shown that evolution of void ratio with vertical effective stress for Shiraz structured fine soil can be reasonably simulated using constitutive equations reported in the literature.