Small strain stiffness in overconsolidated Pliocene clays

• Autorzy: Markowska-Lech K. , Lech M. , Bajda M. , Szymanski A.

Warianty tytułu

PL

Sztywność prekonsolidowanych iłów plioceńskich w zakresie małych odkształceń

• Języki publikacji: EN

Abstrakty

EN

A huge development of technical infrastructure, including the construction of many high-rise buildings, roads, railroads and extension of subway lines, took place over the recent years in Poland. Therefore, numerous planned investment projects require geotechnical data documenting the variation of soil parameters found in the subsoil. The shear wave velocity is one of the most important input parameters to represent the stiffness of the soil deposits. This paper focuses on the methods and devices using measurements of the shear wave velocity to estimate the initial shear modulus in cohesive soil. It is preferable to measure VS by in situ wave propagation tests, however it is often economically not feasible in all regions of Poland. Hence, a reliable correlation between shear wave velocity and parameters measured in triaxial cell or static penetration parameters would be a considerable advantage. This study shows results obtained from the bender elements tests and fi eld techniques – seismic cone penetration test and seismic flat dilatometer, performed on overconsolidated cohesive soils in Warsaw. On the basis of the test results possible correlations between shear wave velocity (initial shear modulus), mean effective stress and void ratio are considered and four original empirical relationships are proposed. Moreover, the proposed formulas by two different techniques using triaxial apparatus and also RCPT cone were examined. The proposed formulas show a reasonable agreement with direct shear wave velocity profiles for clays and might be incorporated into routine laboratory and field practice.

PL

Rozwój infrastruktury technicznej, w tym budowa wysokich budynków, dróg, linii kolejowych i rozbudowy linii metra wymaga danych geotechnicznych dokumentujących zmiany parametrów gruntów występujących w podłożu. Pomiar prędkości fali poprzecznej jest jednym z kluczowych parametrów reprezentującym sztywność podłoża. W niniejszym artykule przedstawione zostały metody i urządzenia mierzące prędkości fali poprzecznej i pozwalające oszacować moduł ścinania gruntu. W artykule przedstawione zostały wyniki badań laboratoryjnych (bender elements) i terenowych (SCPT i SDMT) prekonsolidowanych gruntów spoistych z rejonu Warszawy. Przeprowadzone badania pozwoliły na sformułowanie zależności pomiędzy parametrami mierzonymi w laboratorium a prędkością fali poprzecznej i modułem ścinania. Zaproponowane w artykule zależności zostały poddane weryfi kacji w terenie.

Słowa kluczowe

EN

Pliocene; clay; preconsolidation; deformation; shear modulus; wave velocity

• Wydawca: -
• Czasopismo: Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
• Rocznik: 2013
• Tom: 45
• Numer: 2
• Opis fizyczny: p.170-181,fig.,ref.

Twórcy

autor

Markowska-Lech K.

• Department of Geotechnical Engineering, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland

autor

Lech M.

• Department of Geotechnical Engineering, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland

autor

Bajda M.

• Department of Geotechnical Engineering, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland

autor

Szymanski A.

• Department of Geotechnical Engineering, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland

Bibliografia

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