Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 Analyses
Assessing the constrained modulus is a critical step in calculating settlements in granular soils. This paper describes a novel concept of how the constrained modulus can be derived from seismic tests. The advantages and limitations of seismic laboratory and field tests are addressed. Based on a com...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-12-01
|
| Series: | Geotechnics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2673-7094/4/1/2 |
| _version_ | 1827306112564592640 |
|---|---|
| author | K. Rainer Massarsch |
| author_facet | K. Rainer Massarsch |
| author_sort | K. Rainer Massarsch |
| collection | DOAJ |
| description | Assessing the constrained modulus is a critical step in calculating settlements in granular soils. This paper describes a novel concept of how the constrained modulus can be derived from seismic tests. The advantages and limitations of seismic laboratory and field tests are addressed. Based on a comprehensive review of laboratory resonant column and torsional shear tests, the most important parameters affecting the shear modulus, such as shear strain and confining stress, are defined quantitatively. Also, Poisson’s ratio, which is needed to convert shear modulus to constrained modulus, is strain-dependent. An empirical relationship is presented from which the variation in the secant shear modulus with shear strain can be defined numerically within a broad strain range (10<sup>−4</sup>–10<sup>−0.5</sup>%). The tangent shear modulus was obtained by differentiating the secant shear modulus. According to the tangent modulus concept, the tangent constrained modulus is governed by the modulus number, <i>m</i>, and the stress exponent, <i>j</i>. Laboratory test results on granular soils are reviewed, based on which it is possible to estimate the modulus number during virgin loading and unloading/reloading. A correlation is proposed between the small-strain shear modulus, <i>G</i><sub>0</sub>, and the modulus number, <i>m</i>. The modulus number can also be derived from static cone penetration tests, provided that the cone resistance is adjusted with respect to the mean effective stress. In a companion paper, the concepts presented in this paper are applied to data from an experimental site, where different types of seismic tests and cone penetration tests were performed. |
| first_indexed | 2024-04-24T18:14:50Z |
| format | Article |
| id | doaj.art-854393f83c4f4a42b7cfc83497e34d9a |
| institution | Directory Open Access Journal |
| issn | 2673-7094 |
| language | English |
| last_indexed | 2024-04-24T18:14:50Z |
| publishDate | 2023-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Geotechnics |
| spelling | doaj.art-854393f83c4f4a42b7cfc83497e34d9a2024-03-27T13:43:29ZengMDPI AGGeotechnics2673-70942023-12-0141184010.3390/geotechnics4010002Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 AnalysesK. Rainer Massarsch0Geo Risk and Vibration Scandinavia AB, SE 168 41 Bromma, SwedenAssessing the constrained modulus is a critical step in calculating settlements in granular soils. This paper describes a novel concept of how the constrained modulus can be derived from seismic tests. The advantages and limitations of seismic laboratory and field tests are addressed. Based on a comprehensive review of laboratory resonant column and torsional shear tests, the most important parameters affecting the shear modulus, such as shear strain and confining stress, are defined quantitatively. Also, Poisson’s ratio, which is needed to convert shear modulus to constrained modulus, is strain-dependent. An empirical relationship is presented from which the variation in the secant shear modulus with shear strain can be defined numerically within a broad strain range (10<sup>−4</sup>–10<sup>−0.5</sup>%). The tangent shear modulus was obtained by differentiating the secant shear modulus. According to the tangent modulus concept, the tangent constrained modulus is governed by the modulus number, <i>m</i>, and the stress exponent, <i>j</i>. Laboratory test results on granular soils are reviewed, based on which it is possible to estimate the modulus number during virgin loading and unloading/reloading. A correlation is proposed between the small-strain shear modulus, <i>G</i><sub>0</sub>, and the modulus number, <i>m</i>. The modulus number can also be derived from static cone penetration tests, provided that the cone resistance is adjusted with respect to the mean effective stress. In a companion paper, the concepts presented in this paper are applied to data from an experimental site, where different types of seismic tests and cone penetration tests were performed.https://www.mdpi.com/2673-7094/4/1/2cone penetration testconstrained modulusPoisson’s ratiosandseismic testingshear modulus |
| spellingShingle | K. Rainer Massarsch Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 Analyses Geotechnics cone penetration test constrained modulus Poisson’s ratio sand seismic testing shear modulus |
| title | Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 Analyses |
| title_full | Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 Analyses |
| title_fullStr | Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 Analyses |
| title_full_unstemmed | Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 Analyses |
| title_short | Determination of Constrained Modulus of Granular Soil from In Situ Tests—Part 1 Analyses |
| title_sort | determination of constrained modulus of granular soil from in situ tests part 1 analyses |
| topic | cone penetration test constrained modulus Poisson’s ratio sand seismic testing shear modulus |
| url | https://www.mdpi.com/2673-7094/4/1/2 |
| work_keys_str_mv | AT krainermassarsch determinationofconstrainedmodulusofgranularsoilfrominsitutestspart1analyses |