<abstract xmlns="http://www.w3.org/1999/xhtml">

Stress history acquired by any cohesive soil influences, to a large extent, three groups of fundamental properties indispensable in geotechnical design i.e. state of soil, shear strength, and stiffness characteristics. The basic stress history parameter (from which other parameters are derived) determined directly from laboratory tests is a preconsolidation stress <italic>σ′</italic>p. Since the first method proposed by <xref ref-type="bibr" rid="j_sgem-2023-0017_ref_006">Casagrande in 1936</xref>, value <italic>σ′</italic>p is determined in the oedometer test as a border between overconsolidated (OC) and normally consolidated (NC) zones. Approach based on division between predominantly elastic, (recoverable) strain, and plastic (irrecoverable) strain is a main principle of several methods of <italic>σ′</italic>p determination, which have been proposed over the past eighty-six years.
Accumulated experiences have revealed that any laboratory procedure based on the oedometer test does not provide realistic value of preconsolidation stress, especially in heavy preconsolidated soils. The major reason for that results from the fact that the mechanism responsible for natural overconsolidation is more complicated than mechanical preloading. Therefore, there is a necessity to reevaluate effectiveness of standard methods and look for another solution of evaluation yield stress <italic>σ′</italic>Y in natural soils.
This article presents the comparison between <italic>σ′</italic>Y determined for various soils with use of standard methods based on conventional oedometer test and yield stress determined on the basis of alternative procedures. The latter are represented by various approaches as e.g. based on SHANSEP procedure or initial shear modulus and others. The most promising among these alternative methods is a new concept based on dilatancy phenomenon that takes place during shearing of a dense soil. The parameter reflecting stress history is derived from pore pressure response and is based on characteristic values of Skempton's parameter A record. Consistency of data concerning stress history parameters profile obtained for deep subsoil on the basis of various methods is shown for comparison.
</abstract>

Stress history acquired by any cohesive soil influences, to a large extent, three groups of fundamental properties indispensable in geotechnical design i.e. state of soil, shear strength, and stiffness characteristics. The basic stress history parameter (from which other parameters are derived) determined directly from laboratory tests is a preconsolidation stress σ′p. Since the first method proposed by Casagrande in 1936, value σ′p is determined in the oedometer test as a border between overconsolidated (OC) and normally consolidated (NC) zones. Approach based on division between predominantly elastic, (recoverable) strain, and plastic (irrecoverable) strain is a main principle of several methods of σ′p determination, which have been proposed over the past eighty-six years.
Accumulated experiences have revealed that any laboratory procedure based on the oedometer test does not provide realistic value of preconsolidation stress, especially in heavy preconsolidated soils. The major reason for that results from the fact that the mechanism responsible for natural overconsolidation is more complicated than mechanical preloading. Therefore, there is a necessity to reevaluate effectiveness of standard methods and look for another solution of evaluation yield stress σ′Y in natural soils.
This article presents the comparison between σ′Y determined for various soils with use of standard methods based on conventional oedometer test and yield stress determined on the basis of alternative procedures. The latter are represented by various approaches as e.g. based on SHANSEP procedure or initial shear modulus and others. The most promising among these alternative methods is a new concept based on dilatancy phenomenon that takes place during shearing of a dense soil. The parameter reflecting stress history is derived from pore pressure response and is based on characteristic values of Skempton's parameter A record. Consistency of data concerning stress history parameters profile obtained for deep subsoil on the basis of various methods is shown for comparison.

Reliability of Methods for Determination of Stress History Parameters in Soils

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution 4.0 International License.

{"article-title":"Reliability of Methods for Determination of Stress History Parameters in Soils"}

Stress history acquired by any cohesive soil influences, to a large extent, three groups of fundamental properties indispensable in geotechnical design i.e....

Reliability of Methods for Determination of Stress History Parameters in Soils

Article Category: Special Issue 19th KKMGiIG

Online veröffentlicht: 07. Okt. 2023

Seitenbereich: 350 - 361

Eingereicht: 13. März 2023

Akzeptiert: 18. Aug. 2023

DOI: https://doi.org/10.2478/sgem-2023-0017

Schlüsselwörter
cohesive soils, stress history, preconsolidation stress, lab methods

© 2023 Małgorzata Wdowska et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Reliability of Methods for Determination of Stress History Parameters in Soils

Article Category: Special Issue 19th KKMGiIG

Online veröffentlicht: 07. Okt. 2023

Seitenbereich: 350 - 361

Eingereicht: 13. März 2023

Akzeptiert: 18. Aug. 2023

DOI: https://doi.org/10.2478/sgem-2023-0017

Schlüsselwörtercohesive soils, stress history, preconsolidation stress, lab methods

© 2023 Małgorzata Wdowska et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Schlüsselwörter
cohesive soils, stress history, preconsolidation stress, lab methods