The significance of rate effects in modelling the Sackville test embankment

Abstract

It has been reported that conventional methods of analysis could not adequately 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-viscoplastic constitutive model with an elliptical cap yield surface. The importance of modelling the rate sensitive characteristics of the Sackville foundation soil is demonstrated. A comparison of calculated and measured behaviour of the Sackville test embankment demonstrates that the single elasto-viscoplastic yield surface model adequately described much of the measured time-dependent behaviour of the Sackville test embankment including post construction increases in pore pressure, deformation and reinforcement strain.Key words: Embankment; soft soil; geosynthetic; reinforcement; analysis; field case, viscoplasticity