Experiments of creep rate for over-consolidated clay under plain strain condition and a simple correlation

Abstract

Soft foundations of high embankments exhibit significant time-dependent effect on deformation in decades after construction, and there is a lack of simple method for predicting the creep rate of over-consolidated soft clay under plain strain condition. In this paper, laboratory creep tests under plain strain consolidation with different principal stress ratio were shown. The variation of stress in zero strain direction (σ y ) under different degree of consolidation was analysed. Linear relationship between (σ y ) and the applied principal stress σ x (or σ z ) was found. And then, the creep rate of volumetric strain (C α ) and vertical strain (β) were calculated and linked to volumetric stress defined ratio of over-consolidation (OCR p ) and stress ratio (K). Finally, the new parameter K•OCR p was found to have a good correlation with the creep rate (C α or β).

Creep behaviour of saturated clay subjected to cyclic loading in plain strain condition

“…The isotache model ( [1,2]) was initially proposed for considering the time effect on the settlement of soft soil. Based on the framework of the isotache model, many constitutive models Fukazawa, Shimomura, Murakam, Li et al [17][18][19][20] and Yuzhou et al [21] have been developed which use different assumptions for evaluating the starting time for the secondary compression. They proposed a onedimensional EVP model based on the concept of "equivalent times" during time dependent straining.…”