Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless Soil

Within the strain level attainable in drained triaxial tests, it is not uncommon for dense cohesionless soil to be sheared insufficiently to reach the critical state. Linear fitting of the correlative data from the maximum stress ratio or minimum dilatancy to the end of the test, and then extrapolat...

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Main Authors: Haifeng Zhang, Guohui Lei
Format: Article
Language:English
Published: MDPI AG 2024-01-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/14/2/694
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author Haifeng Zhang
Guohui Lei
author_facet Haifeng Zhang
Guohui Lei
author_sort Haifeng Zhang
collection DOAJ
description Within the strain level attainable in drained triaxial tests, it is not uncommon for dense cohesionless soil to be sheared insufficiently to reach the critical state. Linear fitting of the correlative data from the maximum stress ratio or minimum dilatancy to the end of the test, and then extrapolating these fitted lines to the critical stress ratio or zero dilatancy has been frequently used to estimate the critical state void ratio. However, the linear extrapolation method is empirical and involves different choices of correlative test data, which leads to different estimates. Therefore, a series of simulations of drained tests on dense Toyoura sand are performed using a state-dependent model. Multiple data sets are generated, including void ratio <i>e</i>, volumetric strain <i>ε<sub>v</sub></i>, stress ratio <i>η</i>, and dilatancy <i>D</i>. The linear extrapolation accuracy of the <i>e</i>–<i>η</i>, <i>e</i>–<i>D</i>, and <i>ε<sub>v</sub></i>–<i>D</i> data sets is examined. It turns out that the <i>e</i>–<i>η</i> data set is best suited. The goodness of the <i>e</i>–<i>η</i> data set is examined against 18 sets of experimental data on dense sand. In addition, the selection of the start point for extrapolation is shown to influence the estimates. The latter 50% of the post-peak data is found to be reliable.
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spelling doaj.art-47f3d500fb4a4b39953169bafebdb1c52024-01-29T13:43:45ZengMDPI AGApplied Sciences2076-34172024-01-0114269410.3390/app14020694Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless SoilHaifeng Zhang0Guohui Lei1Key Laboratory of Geomechanics and Embankment Engineering of the Ministry of Education, Geotechnical Research Institute, Hohai University, 1 Xikang Road, Nanjing 210024, ChinaKey Laboratory of Geomechanics and Embankment Engineering of the Ministry of Education, Geotechnical Research Institute, Hohai University, 1 Xikang Road, Nanjing 210024, ChinaWithin the strain level attainable in drained triaxial tests, it is not uncommon for dense cohesionless soil to be sheared insufficiently to reach the critical state. Linear fitting of the correlative data from the maximum stress ratio or minimum dilatancy to the end of the test, and then extrapolating these fitted lines to the critical stress ratio or zero dilatancy has been frequently used to estimate the critical state void ratio. However, the linear extrapolation method is empirical and involves different choices of correlative test data, which leads to different estimates. Therefore, a series of simulations of drained tests on dense Toyoura sand are performed using a state-dependent model. Multiple data sets are generated, including void ratio <i>e</i>, volumetric strain <i>ε<sub>v</sub></i>, stress ratio <i>η</i>, and dilatancy <i>D</i>. The linear extrapolation accuracy of the <i>e</i>–<i>η</i>, <i>e</i>–<i>D</i>, and <i>ε<sub>v</sub></i>–<i>D</i> data sets is examined. It turns out that the <i>e</i>–<i>η</i> data set is best suited. The goodness of the <i>e</i>–<i>η</i> data set is examined against 18 sets of experimental data on dense sand. In addition, the selection of the start point for extrapolation is shown to influence the estimates. The latter 50% of the post-peak data is found to be reliable.https://www.mdpi.com/2076-3417/14/2/694critical statevoid ratiostress ratiodilatancylinear extrapolation
spellingShingle Haifeng Zhang
Guohui Lei
Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless Soil
Applied Sciences
critical state
void ratio
stress ratio
dilatancy
linear extrapolation
title Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless Soil
title_full Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless Soil
title_fullStr Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless Soil
title_full_unstemmed Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless Soil
title_short Use of Linear Extrapolation to Estimate Critical State Void Ratio from Drained Triaxial Shear Tests on Dense Cohesionless Soil
title_sort use of linear extrapolation to estimate critical state void ratio from drained triaxial shear tests on dense cohesionless soil
topic critical state
void ratio
stress ratio
dilatancy
linear extrapolation
url https://www.mdpi.com/2076-3417/14/2/694
work_keys_str_mv AT haifengzhang useoflinearextrapolationtoestimatecriticalstatevoidratiofromdrainedtriaxialsheartestsondensecohesionlesssoil
AT guohuilei useoflinearextrapolationtoestimatecriticalstatevoidratiofromdrainedtriaxialsheartestsondensecohesionlesssoil