Extended model of shear modulus reduction for cohesive soils

It is essential to obtain shear modulus reduction and damping ratio curves to perform dynamic analyses of earth-cored embankment dams. Many studies have been performed for dynamic properties of clayey soils, but they have been limited for earth core materials of dams. This study conducted resonant column tests to obtain shear modulus reduction (G/Gmax) and damping ratio (D) curves for 31 specimens (17 undisturbed and 14 remolded specimens) from 13 earth-cored embankment dams. Empirical G/Gmax and D curves are proposed for dynamic properties of clayey earth core materials. Fitting curves are provided by using the functional forms of the Ramberg–Osgood and Darendeli models. The observation shows that the undisturbed earth cores yield relatively higher G/Gmax and lower D curves than the remolded cores. G/Gmax curves of compacted earth cores are relatively higher than those of Vucetic and Dobry curves for a similar level of plasticity index. Uncertainty and bias are calculated by performing residual analysis, which shows that there is no clear bias in predicting G/Gmax and the uncertainties between undisturbed earth core materials and natural deposits are at a similar level. A proposed empirical relationship of G/Gmax and D curves for earth core materials can be utilized for dynamic analyses of embankment dams for cases where there is insufficient in situ data.

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Shear modulus degradation model for cohesive soils

Soil Dynamics and Earthquake Engineering ◽

10.1016/j.soildyn.2013.07.003 ◽

2013 ◽

Vol 53 ◽

pp. 210-216 ◽

Cited By ~ 14

Author(s):

P. Subramaniam ◽

Subhadeep Banerjee

Keyword(s):

Shear Modulus ◽

Cohesive Soils ◽

Degradation Model

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Selection of representative shear modulus reduction and damping curves for rock, gravel and sand sites from the KiK-Net downhole array

Natural Hazards ◽

10.1007/s11069-017-2944-x ◽

2017 ◽

Vol 88 (3) ◽

pp. 1741-1768 ◽

Cited By ~ 5

Author(s):

P. Anbazhagan ◽

Athul Prabhakaran ◽

H. Madhura ◽

Sayed S. R. Moustafa ◽

Nassir S. N. Al-Arifi

Keyword(s):

Shear Modulus ◽

Downhole Array ◽

Modulus Reduction ◽

Selection Of

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Predicting Vp and constrained modulus reduction curve based on Vs and shear modulus reduction curve in accordance with poroelastic theory

Géotechnique ◽

10.1680/jgeot.21.00143 ◽

2021 ◽

pp. 1-39

Author(s):

Chi-Chin Tsai ◽

Hsing-Wen Liu ◽

Domniki Asimaki

Keyword(s):

Shear Modulus ◽

Wave Velocity ◽

Poisson’S Ratio ◽

Site Response ◽

Vertical Motion ◽

Poisson's Ratio ◽

Reduction Curve ◽

Constrained Modulus ◽

Poroelastic Theory ◽

Modulus Reduction

The compression wave velocity (Vp) of sediments plays a key role in seismic wave amplification of vertical motion and is required in site response analysis. However, such information is usually lacking during field exploration (e.g., surface wave method) because only shear wave velocity (Vs) is obtained. This study aims to predict Vp based on Vs empirically and theoretically, especially focusing on saturated conditions. The empirical approach is to establish the Vp correlation dependency on Poisson's ratio and Vs, and the theoretical approach is based on poroelastic theory that accounts for the interaction between fluid and soil skeleton. The Engineering Geological Database for the Taiwan Strong Motion Instrumentation Program and the Kiban Kyoshin Network database in Japan are adopted to establish an empirical model and validate poroelastic theory. The validated poroelastic approach is used to develop a constrained modulus reduction curve dependency on the porosity, Vs, Poisson's ratio, and degree of saturation with a shear modulus reduction curve. The proposed approach can be used to develop generic Vp profiles and constrained modulus reduction curves for the site response to vertical motion given a site specific Vs profile.

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Shear Modulus and Damping Ratio of Cohesive Soils

Journal of Earthquake Engineering ◽

10.1080/13632460801888525 ◽

2008 ◽

Vol 12 (6) ◽

pp. 879-913 ◽

Cited By ~ 37

Author(s):

P. Kallioglou ◽

Th. Tika ◽

K. Pitilakis

Keyword(s):

Shear Modulus ◽

Damping Ratio ◽

Cohesive Soils

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Application of Artificial Neural Networks for the prediction of undrained shear modulus in cohesive soils

ce/papers ◽

10.1002/cepa.774 ◽

2018 ◽

Vol 2 (2-3) ◽

pp. 833-838

Author(s):

Grzegorz WRZESIŃSKI ◽

Zbigniew LECHOWICZ ◽

Maria J. SULEWSKA

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Shear Modulus ◽

Cohesive Soils ◽

Artificial Neural ◽

Undrained Shear

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Spreading plastic failure as a mechanism for the shear modulus reduction in amorphous solids

EPL (Europhysics Letters) ◽

10.1209/0295-5075/110/48001 ◽

2015 ◽

Vol 110 (4) ◽

pp. 48001 ◽

Cited By ~ 5

Author(s):

Vijayakumar Chikkadi ◽

Oleg Gendelman ◽

Valery Ilyin ◽

J. Ashwin ◽

Itamar Procaccia ◽

...

Keyword(s):

Shear Modulus ◽

Amorphous Solids ◽

Plastic Failure ◽

Modulus Reduction

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Influence of grain size distribution on dynamic shear modulus of sands

Open Engineering ◽

10.1515/eng-2017-0036 ◽

2017 ◽

Vol 7 (1) ◽

pp. 317-329 ◽

Cited By ~ 2

Author(s):

Ireneusz Dyka ◽

Piotr E. Srokosz ◽

Marcin Bujko

Keyword(s):

Grain Size ◽

Shear Modulus ◽

Size Distribution ◽

Grain Size Distribution ◽

Soil Mechanics ◽

Dynamic Shear Modulus ◽

Cohesive Soils ◽

Dynamic Shear ◽

Bender Element ◽

Practical Applications

AbstractThe paper presents the results of laboratory tests, that verify the correlation between the grain-size characteristics of non-cohesive soils and the value of the dynamic shear modulus. The problem is a continuation of the research performed at the Institute of Soil Mechanics and Rock Mechanics in Karlsruhe, by T. Wichtmann and T. Triantafyllidis, who derived the extension of the applicability of the Hardin’s equation describing the explicite dependence between the grain size distribution of sands and the values of dynamic shear modulus. For this purpose, piezo-ceramic bender elements generating elastic waves were used to investigate the mechanical properties of the specimens with artificially generated particle distribution. The obtained results confirmed the hypothesis that grain size distribution of non-cohesive soils has a significant influence on the dynamic shear modulus, but at the same time they have shown that obtaining unambiguous results from bender element tests is a difficult task in practical applications.

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Effects of current suction ratio and recent suction history on small-strain behaviour of an unsaturated soil

Canadian Geotechnical Journal ◽

10.1139/t11-097 ◽

2012 ◽

Vol 49 (2) ◽

pp. 226-243 ◽

Cited By ~ 44

Author(s):

C.W.W. Ng ◽

J. Xu

Keyword(s):

Shear Modulus ◽

Unsaturated Soil ◽

Unsaturated Soils ◽

Small Strain ◽

Triaxial Tests ◽

Stress History ◽

Reduction Curve ◽

Small Strain Shear Modulus ◽

Suction History ◽

Modulus Reduction

Although the small-strain shear modulus of saturated soils is known to be significantly affected by stress history, consisting of the overconsolidation ratio (OCR) and recent stress history, the effects of suction history on the small-strain shear modulus of unsaturated soils have rarely been reported. In this study, the effects of suction history, which refers to current suction ratio (CSR) and recent suction history, on both the very-small-strain shear modulus (G0) and shear modulus reduction curve of an unsaturated soil, are investigated by carrying out constant net mean stress compression triaxial tests with bender elements and local strain measurements. In addition, the effect of suction magnitude on G0 and the shear modulus reduction curve is also investigated. At a given suction, G0, elastic threshold strain (εe), and the rate of shear modulus reduction all increase with CSR. On the other hand, the effect of recent suction history on G0 is not significant. The effect of direction of recent suction path (θ) on the shear modulus reduction curve is not distinct. However, the magnitude of recent suction path (l) affects the shear modulus reduction curve significantly when θ = –90°.

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