...
For
...
...
static,
...
and
...
nonlinear
...
...
...
analyses,
...
users
...
may
...
simulate
...
...
behavior
...
by
...
assigning
...
concentrated
...
plastic
...
hinges
...
to
...
...
and
...
...
objects.
...
Elastic
...
behavior
...
occurs
...
over
...
member
...
length,
...
then
...
deformation
...
beyond
...
the
...
elastic
...
limit
...
occurs
...
entirely
...
within
...
hinges,
...
which
...
are
...
modeled
...
in
...
discrete
...
locations.
...
Inelastic behavior is obtained through integration of the plastic strain and plastic curvature which occurs within a user-defined hinge length, typically on the order of member depth (FEMA-356).
...
To
...
capture
...
plasticity
...
distributed
...
along
...
member
...
length,
...
a
...
series
...
of
...
hinges
...
may
...
be
...
modeled.
...
Multiple
...
hinges
...
may
...
also
...
coincide
...
at
...
the
...
same
...
location.
...
Plasticity
...
may
...
be
...
associated
...
with
...
force-displacement
...
behaviors
...
(axial
...
and
...
shear)
...
or
...
moment-rotation
...
(torsion
...
and
...
bending).
...
Hinges
...
may
...
be
...
assigned
...
(uncoupled)
...
to
...
any
...
of
...
the
...
six
...
DOF.
...
Post-yield
...
behavior
...
is
...
described
...
by
...
the
...
general
...
backbone
...
relationship
...
shown
...
to
...
the
...
right.
...
The
...
modeling
...
of
...
strength
...
loss
...
is
...
discouraged,
...
to
...
mitigate
...
load
...
redistribution
...
(which
...
may
...
lead
...
to
...
progressive
...
collapse)
...
and
...
to
...
ensure
...
numerical
...
convergence
...
.
...
Software
...
automatically
...
limits
...
negative
...
slope
...
to
...
10%
...
of
...
elastic
...
stiffness,
...
though
...
overwrite
...
options
...
are
...
available.
...
For
...
informational
...
purposes,
...
additional
...
limit
...
states
...
(IO,
...
LS,
...
CP)
...
may
...
be
...
specified
...
which
...
are
...
reported
...
in
...
analysis,
...
but
...
do
...
not
...
affect
...
results.
...
Unloading
...
from
...
the
...
point
...
of
...
plastic
...
deformation
...
follows
...
the
...
slope
...
of
...
initial
...
stiffness.
...
Both P-M2-M3
...
...
and
...
...
...
are
...
available
...
to
...
capture
...
coupled
...
axial
...
and
...
biaxial-bending
...
behavior.
...
The
...
P-M2-M3
...
hinge
...
is
...
best
...
suited
...
for
...
nonlinear
...
static
...
pushover,
...
whereas
...
the
...
fiber
...
hinge
...
is
...
best
...
for
...
hysteretic
...
dynamics.
...
Additional
...
information
...
on
...
hinges
...
can
...
be
...
found
...
in
...
the
...
...
...
...
(Frame
...
Hinge
...
Properties,
...
page
...
131).
...
| List of resources2 |
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