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Title: Influence of Natural Soil Fabric on the Cyclic Resistance of Low and High Plasticity Silts
This paper presents the results from a study of the role of soil fabric on the cyclic response of silty soil samples retrieved from two different sites from a series of sites investigated as a part of a larger study: one along the Willamette River (Site B) and one along the Columbia River (Site D). The soils investigated in this study were retrieved from Site B and exhibited an average 𝑃𝐼=13, and from Site D which were characterized with an average 𝑃𝐼=28. The cyclic response of the soils was evaluated by performing several constant-volume, stress-controlled, cyclic direct simple shear tests (CDSS) with varying cyclic stress ratios, CSRs, on natural, intact specimens and their reconstituted counterparts. Despite the lower void ratios of the reconstituted specimens, the cyclic resistance of the intact specimens for Sites B and D at 15 loading cycles were 19% and 37% greater than their reconstituted counterparts, respectively. For the given loading conditions, the rate of excess pore pressure development, single amplitude shear strain (𝛾) accumulation, and shear stiffness degradation in reconstituted specimens were greater than the natural intact specimens, emphasizing the role of soil fabric, as confirmed by the lower shear wave velocity (𝑉𝑠) of reconstituted specimens compared to their intact counterparts.  more » « less
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12th National Conference on Earthquake Engineering
Medium: X
Sponsoring Org:
National Science Foundation
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