Page 265 - Marine Structural Design
P. 265
Chapter 12 A Theoly of Nonlinear Finite Element Analysis 24 1
1
ax =ax -am, 0, =ay -urn, 6, =az -am,
ax +ay +a,
lYm = t (A. 12)
3 ’
zxy =tmr rv =rp, r, =z,
The most widely used yield criterion for metallic materials is Mises’s yield criterion, in which
the hnction f in Eq.(A.l 1) is only expressed as a function of the secondary invariant of
deviatoric stress, J’, .
f =J3J,-ao (A. 13)
where, 0, is the yield stress for the uniaxial loading. Here, J’, is ,
.I; -(a;a; + 6;a; + a;a;)+ r; + r; + rg
=
(A. 14)
If the equivalent stress a is defined as,
(A. 15)
Figure A.4 Isotropic Hardening Rule.
