multiPlas - Dynardo GmbH

This model guaranties a consistent dissipation of fracture energy during the softening process for different
sizes of elements. The stress-strain lines available in multiPlas are shown in Fig. 3-13. Thereby, a linear
elastic behaviour is assumed until the tensile strength is reached. After that, one of the following is
assumed as consequence of tensile fracturing:
** linear softening until the strain limit is reached εtr (mlaw = 0, 2) or
** exponential softening (mlaw = 1)
σ
Fig. 3-13 Stress-strain relation in multiPlas (mlaw=0, 2; mlaw = 1)
For the exponential softening model (mlaw = 1) one should assume
G E
h ≤ (3-24)
f
f
2
t
Über h gemittelte Spannungs-Dehnungslinie
f t
f t/E
(a)
(b)
"Snap-Back", wenn h groß
ε tr
h PR h
for the length h in order to avoid the numerically unstable „snap-back“ phenomena. This is preferably
achieved by choosing a proper mesh size. In multiPlas, the equivalent length will calculated automatically.
(a)
(b)
h PR
19
USER’S MANUAL, January, 2013
h
ε