Creep model of over-consolidated soft clay under plane strain

All right reserved. The creep behavior of over-consolidated soft clay was studied through plane strain tests for undisturbed soft clay using a new measuring device. The results show that the new measuring device can measure the lateral deformation of over-consolidated soft soil under plane strain and eliminate the influence of the accuracy in volumetric deformation measurement. There is a good correlation between the lateral deformation and the over-consolidation shear stress ratio (OCRq), and the OCRqreflects the effects of shear stress and stress history on the lateral deformation. Both the volumetric creep coefficient and the axial creep coefficient have a good correlation with the OCRq. On the basis of the plane strain creep tests to the over-consolidated soft soil under different principal stress ratios, an empirical model with four parameters was developed. The variables in the model are the principal stress ratio and OCRq. The empirical model takes into consideration of the normally consolidated state of soft soils and reflects reasonably the influence of principal stress ratio and stress history in the creep process under plane strain condition.