Sand response to a large number of loading cycles under zero-lateral-strain conditions: evolution of void ratio and small-strain stiffness

The significance of small-strain stiffness (Gmax) of saturated composite soils are still of great concern in practice, due to the complex influence of fines on soil fabric. This paper presents an experimental investigation conducted through comprehensive bender element tests on Gmax of marine silty sand. Special attention is paid to the influence of initial effective confining pressure ( σ c 0 ′ ), global void ratio (e) and fines content (FC) on Gmax of a marine silty sand. The results indicate that under otherwise similar conditions, Gmax decreases with decreasing e or FC, but decreases with increasing FC. In addition, the reduction rate of Gmax with e increasing is not sensitive to σ c 0 ′ , but obviously sensitive to changes in FC. The equivalent skeleton void ratio (e*) is introduced as an alternative state index for silty sand with various FC, based on the concept of binary packing material. Remarkably, the Hardin model is modified with the new state index e*, allowing unified characterization of Gmax values for silty sand with various FC, e, and σ c 0 ′ . Independent test data for different silty sand published in the literature calibrate the applicability of this proposed model.

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Small to intermediate strain properties of fly ashes with various carbon and biomass contents

Canadian Geotechnical Journal ◽

10.1139/cgj-2014-0069 ◽

2016 ◽

Vol 53 (1) ◽

pp. 35-48 ◽

Cited By ~ 4

Author(s):

H. Choo ◽

N.N. Yeboah ◽

S.E. Burns

Keyword(s):

Void Ratio ◽

Small Strain ◽

Interparticle Contact ◽

Bender Elements ◽

Fly Ashes ◽

Small Strain Stiffness ◽

Initial Void Ratio ◽

Constrained Modulus ◽

Stiffness Anisotropy ◽

Biomass Particles

High-carbon-content fly ashes with biomass particles are typically landfilled in accordance with the ASTM C618 regulation. To quantify their geotechnical properties relating to storage and disposal, this study evaluates the small to intermediate strain properties of fly ashes with various carbon and biomass contents. Tested fly ashes had carbon contents ranging from 1.1% to 9.6%, resulting from co-combusting coal with biomass (biomass contents ranging from 0% to 8.2% by weight). The small-strain stiffness and intermediate-strain constrained modulus were evaluated using consolidation tests performed in a modified oedometer cell equipped with bender elements. It was found that initial void ratio governed the compressibility (or constrained modulus) of fly ashes, and with an increase in carbon and biomass contents, the small-strain stiffness of fly ashes decreased due to the decrease in number of direct contacts between microspheres. In addition, the interfine void ratio, ef, was employed instead of global void ratio to capture the alteration of interparticle contact or interparticle coordination between microspheres, due to the change in carbon and biomass contents. Finally, the stiffness in an overconsolidated state and the stiffness anisotropy of fly ashes were evaluated.

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Small Strain Stiffness and Non-Linear Stress-Strain Behaviour of Cement-Mixed Gravelly Soil

SOILS AND FOUNDATIONS ◽

10.3208/sandf.47.375 ◽

2007 ◽

Vol 47 (2) ◽

pp. 375-394 ◽

Cited By ~ 14

Author(s):

Lalana Kongsukprasert ◽

Fumio Tatsuoka

Keyword(s):

Small Strain ◽

Stress Strain ◽

Small Strain Stiffness ◽

Strain Behaviour ◽

Gravelly Soil ◽

Non Linear

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Estimation of the Small-Strain Stiffness of Clean and Silty Sands using Stress-Strain Curves and CPT Cone Resistance

SOILS AND FOUNDATIONS ◽

10.3208/sandf.49.545 ◽

2009 ◽

Vol 49 (4) ◽

pp. 545-556 ◽

Cited By ~ 2

Author(s):

Junhwan Lee ◽

Doohyun Kyung ◽

Bumjoo Kim ◽

Monica Prezzi

Keyword(s):

Small Strain ◽

Stress Strain ◽

Cone Resistance ◽

Small Strain Stiffness

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Effect of cementation on the small-strain stiffness of granite residual soil

SOILS AND FOUNDATIONS ◽

10.1016/j.sandf.2021.02.001 ◽

2021 ◽

Vol 61 (2) ◽

pp. 520-532

Author(s):

Xinyu Liu ◽

Xianwei Zhang ◽

Lingwei Kong ◽

Xinming Li ◽

Gang Wang

Keyword(s):

Small Strain ◽

Residual Soil ◽

Small Strain Stiffness ◽

Granite Residual Soil

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Small strain stiffness of carbonate Kenya Sand

Engineering Geology ◽

10.1016/j.enggeo.2013.04.006 ◽

2013 ◽

Vol 161 ◽

pp. 65-80 ◽

Cited By ~ 22

Author(s):

V. Fioravante ◽

D. Giretti ◽

M. Jamiolkowski

Keyword(s):

Small Strain ◽

Small Strain Stiffness

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Small strain stiffness for granite residual soil: effect of stress ratio

Canadian Geotechnical Journal ◽

10.1139/cgj-2021-0308 ◽

2021 ◽

Author(s):

Xianwei Zhang ◽

Xinyu Liu ◽

Lingwei Kong ◽

Gang Wang ◽

Cheng Chen

Keyword(s):

Stress Ratio ◽

Small Strain ◽

Residual Soil ◽

Resonant Column ◽

Residual Soils ◽

Column Tests ◽

Small Strain Stiffness ◽

Deviator Stress ◽

Granite Residual Soil ◽

Stress Ratios

Most previous studies have focused on the small strain stiffness of sedimentary soil while little attention has been given to residual soils with different properties. Most studies also neglected the effects of the deviator stress, which is extensively involved in civil engineering. This note considers the effects of the deviator stress on the small-strain stiffness of natural granite residual soil (GRS) as established from resonant column tests performed under various stress ratios. Although increasing the stress ratio results in a greater maximum shear modulus for both natural and remolded residual soils, remolded soil is more sensitive to changes in the stress ratio, which highlights the effects of soil cementation. The data herein offers new insights to understand the stiffness of residual soil and other weathered geomaterials.

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