Interpretation of shear modulus degradation tests

• Autorzy: Srokosz P. , Dyka I. , Bujko M.

Identyfikatory

DOI

10.2478/sgem-2018-0015

• Języki publikacji: EN

Abstrakty

EN

The problem is a continuation of the research conducted at the University of Warmia and Mazury in Olsztyn, Institute of Building Engineering. It concerns the development of methods for the interpretation of the shear modulus measurements based on the tests conducted on a torsional shear (TS) apparatus. The issue has significant importance in determining the deformation parameters, essential to perform numerical simulations of the interaction between a geotechnical structure and the subsoil. The purpose of this study was to conduct a comparative analysis of the various methods of interpretation of research results based on direct and reverse analysis, as well as automated classification of the first cycle of the relationship between the shear stress and the shear strain components obtained from the TS test. The methodology for verification of the presented interpretative methods consists in carrying out a series of laboratory tests on non-cohesive and cohesive samples of different granulation and state parameters. The course of the research includes the following steps: elaboration of the granulometric composition of several samples of soil, determination of soil index properties and execution of TS tests. Various methods of interpretation of obtained results were taken into account, in addition to conducting a comparative analysis. The study used a non-standard interpretation approach consisting of analysing onefourth of the hysteresis loop of the first load-unload cycle of the tested samples. The obtained results confirmed the hypothesis that it is possible to estimate the degradation value of the shear modulus based on a part of the TS test results carried out under quasi-monotonic load conditions. The proposed methods of interpreting test results have confirmed their high usefulness, which is devoid of the uncertainty associated with standardised resonant column/TS testing.

Słowa kluczowe

EN

torsional shear; back analysis; cluster analysis; shear modulus; small strains

• Wydawca: De Gruyter
• Czasopismo: Studia Geotechnica et Mechanica
• Rocznik: 2018
• Tom: Vol. 40, nr 2
• Strony: 125--132
• Opis fizyczny: Bibliogr. 21 poz., rys., tab.

Twórcy

autor

Srokosz P.

• Faculty of Geodesy, Geospatial and Civil Engineering, University of Warmia and Mazury in Olsztyn

autor

Dyka I.

• Faculty of Geodesy, Geospatial and Civil Engineering, University of Warmia and Mazury in Olsztyn

autor

Bujko M.

• Faculty of Geodesy, Geospatial and Civil Engineering, University of Warmia and Mazury in Olsztyn

Bibliografia

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Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2018).