Page 232 - Analysis and Design of Energy Geostructures

Deformation in the context of energy geostructures 205

jj. The concept of critical state plasticity is associated with the
mechanical behaviour of materials for which a continuous distor-
tion caused by shearing eventually leads to a well-defined critical
state. Under critical state conditions, the material flows as a fric-
tional fluid, so that yielding occurs at constant volume and con-
stant stresses.
kk. The critical state theory can be employed to describe the mechanical
behaviour of both coarse- and fine-grained materials.
a. True
b. False
ll. The critical state line (CSL) can be identified in the relevant planes
q 2 p and v e 2 lnp as

q 5 M c p

~
Γ 5 v e 1 λlnp

mm. The concepts of multisurface and bounding plasticity are aimed at
capturing with accuracy the mechanical behaviour of materials
characterised by a smooth transition from a reversible to an irre-
versible behaviour, as well as subjected to reversal (i.e. cyclic)
loadings.