The variation of stress during creep convergence of a deep borehole excavat
ed in rock salt is examined. A non-associated elasto/viscoplastic constitut
ive equation is used to describe both compressibility and/or dilatancy duri
ng transient and steady-state creep, as well as evolutive damage possibly l
eading to failure. An in-house FEM numerical method is used for this purpos
e. The variation in time of radial convergence of the borehole walls and of
the stress state (at various distances from the borehole surface) is illus
trated by several figures. The significance of these variations for long-te
rm stability is discussed. (C) 2001 Elsevier Science Ltd. All rights reserv
ed.