MSC Nastran; Patran Tutorial - Linear Statics; Pinned Truss Analysis Video

in this video I will be performing a
linear static analysis on this pin
troughs full details of this problem are
available on page 359 of the PDF linked
in the video description below
first thing I'll go ahead and do is
switch over to my new patch Ron database
per session I'll start a new patch on
database I'll call a problem a my units
for this exercise are inches pounds psi
and degrees Fahrenheit I'll click OK on
this dialog for my model all created
from scratch using only nodes and
elements so I'll go to my meshing tab
and here under node I'll click Edit and
here I'll create 4 nodes one of my
origin want to add 20 inches in the X
went at 20 inches in the X and y1 at 20
inches vertically up hit enter or apply
and you'll notice that the nodes are
just tiny points to reveal them I will
go back here and click node size and
you'll see one here here here and here
now I have to link the nodes together
with an element so go to the meshing tab
here click Edit for element your shape
will be a bar and simply connect a dots
so lmm 1 is from here to here element 2
is from here to here element 3 is from
here to here force from here to here 5
is from here to here and 6 is from here
to here so now I have the trust so I can
create my material and assign them to
this these elements by going to this tab
click isotropic call this material just
material
for input properties give it a Young's
modulus of 1 e 7 psi and Poisson ratio
0.3 your thermal expansion coefficient
is 1 e to the negative 6 or 1e negative
6 click OK and click apply you've
created this material it's time to
assign them to the various rods here so
under when do properties click rod two
elements in here have an area of point
seven zero seven inches that would be
this diagonal in this diagonal so I will
first call this rod to and forward to
apply two elements two and four this is
my name so then I go under input
properties and I select the material I
just created my area is 0.7 zero seven
inches click OK and apply it to these
two members and make sure you have this
beam element icon selected this allows
me to select just beam elements so so
like elements two and four
click OK and apply now for my next
property for the rest of the elements
one three five and six
my area is one inch my application
region would be these other elements so
select them add them okay and apply now
I can go on to define my boundary
conditions so I'll first create two pins
call it my XY pins so they prevent
translation in the x and y directions so
zero on the x is 0 on the y and the
freeze and the Z is free to translate at
the moment for application region we're
applying this directly to the fam or the
nodes so I'm just dragging so like these
two leftmost no
click ok and apply now we'll apply
restraints so this is not allowed to
move in the Z direction so here we'll
just call this next one Z constraint for
input data leave every t1 and t2 blank
except for t3 add a zero there click OK
or your application regions select all
the nodes you'll see they're circled in
a sort of pink square add them ok and
apply now I have to add my element
uniform temperature loads
so here's it zero degrees Fahrenheit
will be applied to all only one D
elements your Impa data will be just 0
degrees click OK your application region
just select every element except this
one add it added ok and apply I'll make
a new one called 100 F grandpa data it's
100 degrees Fahrenheit select this
element here added ok and apply now I
can run my analysis for the entire model
before I go ahead and do that I want to
modify my sub case so I'll modify a
default sub case by highlighting it my
output request I wish to output element
forces so make sure you have
displacement stress and force here so
I'll include it in this list click apply
here or you can click OK here on the
bottom or apply whichever is there click
on so after you hit apply hit apply to
submit the job to the embassy Nastran
once the analysis is done I'll reset the
graphics here to clean it up
reorient this to view it from the front
and now I can import my xtb results let
me go ahead and turn off these node
icons here
so here I've selected and I've hit apply
it's imported the results so now can
view various things so for my
displacements here under vector I would
display vectors indicating the
displacements so here I select
displacements translational amounts of
you components just in the X so when I
hit apply see my arrows here so I get up
1.82 and 1.82 here and I believe that is
not correct so I should be getting one
point two seven and seven point two
seven so when I look at this problem
again I forgot to include my load here
at this node so to add this I will have
to go back to my boundary conditions tab
under nodal force apply a load called F
and this load is 0 in the X 1000 and the
Y and 0 in the Z click OK your
application regions simply make sure
this is selected to FEM so you can only
select nodes select this node add it ok
and apply so now have all my boundary
conditions now can reanalyze this by
going to analysis analyze entire model
when I hit apply I'll be asked to
overwrite the previous job files and you
just click yes for bold dialogues once
that's done and forth X DB results click
apply under results go back to vector
select this result case select
displacements translational and for show
a select component xx and after you hit
apply
you get a one point two zero point zero
zero one to seven inches and this value
here for the bottom
and when you compare it to what we
should get we actually do get those
values now for the y-direction let me
clean this up simply switch that YY on
turn off xx turn it on or hit apply so
we get a six point three six and three
point six four six point three six and
three point six four so here for p1 we
get
mmm a compressive value or an element
force of six hundred three six pounds to
view that you're still in vector you
move up and select bar forces from
component you press or check X X and x
axis basically along the line so even if
diagonal X X element x axis down the
line so I'm going to hit apply I would
have to do is here select elements if I
had apply them and I do it yet what I
have to do is here's select none here's
select all the elements
imma love this thing I'm going to do
well I'm going to do that yet hit apply
and here you have a view of all the
values and they're not easy to read what
I can do is switch the suffix
click OK and hit apply so now I know
this has a force of 1 636 363 363 514
and 900 I'm going to look at these
values I get 636 900 363 514 363 and 0
and that conference what I get here now
to view the stresses I go back to select
results scroll to the bottom
click stress sensor here select
component for quantity and I want to
view my stresses and extractions so I
leave this checked click apply now I can
read it off as 363 and there should be
no difference for the bars with the area
of one inch squared we will notice the
difference for the diagonals so let me
go ahead and confirm the values of 727
12 72 that's what we get here and the
other ones should be the same as bar
forces with the area taking into account
clean it up save and the sense of this
exercise