ABSTRACT
This paper describes the results of an experimental programme carried out to evaluate the influence of relatively fast thermal pulses on the stiffness degradation of two Tertiary argillaceous rocks (a plastic clay rock and a stiff claystone). Heating pulses were performed using a specially developed setup installed in a microwave oven. Low-strain shear moduli using bender elements were measured before and after each of the heating pulses to track the evolution of the thermally induced degradation. An important stiffness reduction was observed on both samples. In addition, mercury intrusion porosimetry tests to analyse the pore size distribution changes between unaltered and post-mortem samples were performed to have further insight into the degradation phenomena undergone by the materials.
