April 18, 2011
|
RISA-3D,
Loads,
New
RISA-3D
will
now
check
your
model
for
errors
by
summing
the
reactions
in
your
model
and
comparing
them
to
the
applied
loads.
This
occurs
for
the
global
X,
Y,
and
Z
directions.
If
RISA
identifies
that
the
reactions
do
not
equal
the
applied
loads
then
the
software
will
show
a
warning
message
to
the
user.
There
are
three
main
reasons
why
this
might
happen:
You
have
used
a
Fixed
call
out
in
the
Boundary
Conditions
spreadsheet:
There
are
instabilities
in
your
model,
causing
locked
joints:
These
locked
joints
may
have
an
actual
reaction
coming
out,
but
because
the
program
was
forced
to
lock
it
there
is
no
calculation
of
this
reaction.
Fix
the
instabilities
and
the
message
will
likely
go
away.
Areas
of
high
rigidity
simulating
boundary
conditions
(sometimes
referred
to
as
ghost
reactions):
If
you
have
an
area
of
your
model
that
has
a
concentrated
amount
of
very
stiff
elements
and/or
single
elements
that
have
very
high
stiffness,
then
these
areas
may
approach
the
stiffness
of
a
boundary
condition
and
erroneously
take
load
out
of
your
model.
Common
reasons
why
this
might
happen:
Setting
the
E
and
I
values
for
your
Material
or
Section
Set
overly
high.
A
rule…
