ABSTRACT
In recent years many researches have shown that
rock salt exhibits pronounced time-dependent de-
formation or creep under relatively low stress level
and has low permeability and porosity. Rock salt
creeps to a large strain without fracturing and tends
to be self-healing. So rock salt is often considered as
an ideal material for storage of natural gas, petro-
leum and wastes, or nuclear waste (Yang et al.
