Creep Behaviour and Constitutive Equation of Sanjome Andesite and Kawazu Tuff

Abstract

Special attention has been given in this study to measure the strain-time characteristics of samples in tertiary creep. Tertiary creep is signified by a continuous increase of strain rate. An interesting feature of this strain rate increase was found; The strain rate ata certain time in tertiary creep is inversely proportional to the time up to final failure.A constitutive equation has been proposed based on the experimental results of creep.The simulation was carried out numerically and the calculated results were compared with the experimentally obtained stress-strain curves.The calculated ones well coincide with theexperimental. It should be emphasized that the proposed constitutive equation can be applied to not only pre-failure region but also post-failure region to some extent.