ABSTRACT
Viscous Properties of Geomaterials E.FLAVIGNY & R.NOVA
Institut de Mécanique de Grenoble, France
1 INTRODUCTION
It is well known that time has an effect on the mechanical properties of geomaterials-soils, concrete or rocks. This effect is closely connected to a degradation of properties which is revealed by creep and relaxation phenomena, and by the influence of rate of strain. Several points arise: (1) What is the importance of the viscous part of the behaviour in comparison with the elastoplastic behaviour, which is often the only one considered? (2) How does one measure this effect in a laboratory without recourse to very long experiments, which are inevitably expensive? (3) For this reason the experimental basis available, which is the starting point for any constitutive modelling, is quite restricted.
