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http://dx.doi.org/10.12814/jkgss.2017.16.3.041

Evaluation on Undrained Shear Strength considering Consolidation Characteristics for Busan Clay  

Kim, Ju-Hyun (Department of Civil Engineering, Dongshin University)
Publication Information
Journal of the Korean Geosynthetics Society / v.16, no.3, 2017 , pp. 41-49 More about this Journal
Abstract
In this study, a series of laboratory and in-situ tests such as FVTs and CPTUs were carried out to evaluate undrained shear strength related to quasi overconsolidated characteristics in the near-surface clay at Busan new port. Using unconfined compression and field vane test results, correlation between undrained shear strength and effective overburden pressure, that is, equation of $10+0.262{\sigma}^{\prime}v_0$ (kPa) was obtained. From oedometer tests, OCR is around 1.9 at depths lower than 7 m and OCR below this depth is very close to unit. As stated by Hanzawa et al. (1983), a natural clay deposit in the near-surface, even in normally consolidated state, is more and less apparently overconsolidated due to aging effects such as chemical bonding. Based on this concept, it can be inferred that intercept of equation is mobilized due to chemical bonding irrespective of effective overburden pressure and strength incremental ratio in normally consolidated state is 0.262. From CPTU results, same trend was confirmed. The further study should be necessary to judge whether upper clay is under overconsolidated state due to chemical bonding or not based on the depositional environment.
Keywords
Chemical bonding; Undrained shear strength; Quasi-overconsolidated characteristics; Aging effects;
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Times Cited By KSCI : 2  (Citation Analysis)
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