...
Unlinking
...
a
...
parametric
...
model
...
The
...
bridge
...
model
...
should
...
be
...
developed
...
using
...
one
...
of
...
the
...
parametric
...
definitions
...
of
...
the
...
Bridge
...
menu.
...
Users
...
may
...
then
...
make
...
manual
...
changes
...
using
...
the
...
Bridge
...
>
...
Update
...
Linked
...
Bridge
...
Model
...
>
...
Convert
...
to
...
Unlinked
...
Model
...
option.
...
This
...
should
...
only
...
be
...
done
...
to
...
finalize
...
the
...
bridge
...
model,
...
however,
...
in
...
that
...
users
...
will
...
no
...
longer
...
have
...
the
...
advantages
...
of
...
parametric
...
definition.
...
Further,
...
users
...
may
...
want
...
to
...
copy
...
the
...
file
...
before
...
converting
...
to
...
an
...
unlinked
...
model.
...
Users
...
will
...
then
...
have
...
the
...
option
...
to
...
revert
...
to
...
a
...
previous
...
version
...
in
...
case
...
parametric
...
changes
...
are
...
necessary.
...
Please
...
ensure
...
that
...
design
...
done
...
using
...
the
...
bridge
...
modeler
...
is
...
not
...
overwritten
...
during
...
linked
...
model
...
update.
...
Verify moving-load
...
analysis
...
using
...
a
...
static
...
load
...
case
...
A
...
moving-load
...
analysis
...
envelopes
...
the
...
internal
...
forces
...
resulting
...
from
...
a
...
series
...
of
...
possible
...
truck
...
locations.
...
Users
...
may
...
verify
...
step-by-step
...
and
...
influence-based
...
moving-load
...
analysis
...
results
...
through
...
a
...
simple
...
static
...
load
...
case.
...
Static
...
loads
...
simulating
...
truck
...
positioning
...
should
...
induce
...
maximum
...
response
...
for
...
the
...
parameter
...
being
...
observed.
...
Static
...
response
...
should
...
be
...
equal
...
to
...
or
...
slightly
...
less
...
than
...
the
...
moving-load
...
results.
...
Multiple vehicles in a single lane
Users may model multiple vehicles acting simultaneously on a single lane by specifying a Special Vehicle on the General Vehicle Data form. This vehicle should be defined to include two vehicles separated by a fixed or variable distance. For example, two HL93 trucks would contain six axles, three for each vehicle.
Pinned condition for both abutment and bearings
Local instability will arise when both the abutment bearing and the abutment foundation spring are defined as pinned. To provide for rotational stiffness at the abutment, one of these two links should be fully fixed.
Mixed model introduction
A mixed model is a bridge system designed using both the bridge modeler and the conventional software interface. Mixed modeling may be necessary for irregular, specialty, or highly customized systems. The typical procedure entails building the model core using parametric features of the bridge modeler, then unlinking the model to incorporate elements for which templates are not provided.
Please see the mixed modeling article for more information.