The significance of rate effects in modelling the Sackville test embankment

It has been reported that conventional methods of analysis could not adequa tely describe all aspects of the behaviour of a geotextile-reinforced test embankment constructed to failure on a soft clayey silt with some organics at Sackville, New Brunswick (Canada). This paper presents the results of an analysis of the Sackville embankment using a fully coupled elasto-viscopla stic constitutive model with an elliptical cap yield surface. The importanc e of modelling the rate sensitive characteristics of the Sackville foundati on soil is demonstrated. A comparison of calculated and measured behaviour of the Sackville test embankment demonstrates that the single elasto-viscop lastic yield surface model adequately described much of the measured time-d ependent behaviour of the Sackville test embankment including post construc tion increases in pore pressure, deformation and reinforcement strain.