The influence of overconsolidation ratio on the "Gs - ε 1" dependence for cyclic loading of cohesive soils in the range of small strains

• Autorzy: Jastrzębska M.
• Języki publikacji: EN

Abstrakty

EN

The subject of the paper comprises testing of a cohesive soil response to cyclic loading applied in the range of small strains (10(-5)÷10(-3)). To this end, tests of undrained cyclic shear in a triaxial apparatus were carried out on homogeneous material - kaoline from Tułowice. The tests were carried out on a modernised test bed, enabling full saturation of specimens using the back pressure method as well as a precise, local measurement of small strains by means of contactless microdisplacement sensors. While maintaining a constant deformation rate, during 10 cycles of unloading and reloading, the influence of overconsolidation ratio (OCR) at various levels of the deviator stress amplitude (A1 = 0.75∇q and A2 = 0.375∇q ) on the "Gs - ε 1" stiffness characteristics was investigated. When analysing the results obtained it has been found that the overconsolidated soils feature higher Gs values as compared with normally consolidated soils, where the differences are more significant for higher deviator stress amplitudes. In addition, the deviator stress amplitude increase results in a decline in the shear modulus Gs. At the same time soil strengthening in consecutive cycles is observed.

Słowa kluczowe

PL

współczynnik prekonsolidacji; OCR; prekonsolidacja; właściwości gruntu; grunty spoiste; odkształcenia gruntu

• Wydawca: De Gruyter
• Czasopismo: Studia Geotechnica et Mechanica
• Rocznik: 2010
• Tom: Vol. 32, nr 1
• Strony: 23--34
• Opis fizyczny: bibliogr. 20 poz.

Twórcy

autor

Jastrzębska M.

• Silesian University of Technology, Gliwice,

Bibliografia

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