Any possibility to apply forces inside the beam

1

Hello everybody,

valu Etyp he8

preprocessing

geometry

seto beam
pnt p0 0 0 0
pnt p1 10 0 0

line l0 p0 p1
seta se0 l l0

swep se0 se1 tra 0 0 20
swep se1 se2 tra 0 0 40

seta ses1 A001
swep ses1 ses2 tra 0 4 0 2
swep ses2 ses3 tra 0 100 0 10
swep ses3 ses4 tra 0 4 0 2

seta ses5 A002
swep ses5 ses6 tra 0 108 0 10

seta rear A008
seta front A003

setc beam

elty beam Etyp
mesh beam
send beam abq

view elem

send rear abq surf
send front abq surf
send rear abq spc 2
send rear abq pres 12750 # g/mm^2
send front abq pres 12750 # g/mm^2

;; to do this way, it does not work. May someone suggest how to apply press in such situations, please.

plus s rear
does not work as well.

plus n beam
works fine so and I can see the nodes where the press is applied but how to do it, no idea yet.
kg/mm^2 is easy to apply to surface, kg is applied to a node and if there are many nodes I have to kg / number-of-nodes and apply a result to each node then?

2

Hello,
these command send rear abq pres works only if you have faces of elements in your set
please put in the command
prnt se and you will see, that there is 0 with f:0
so you have to use the comp up and down command to put in the neccessary elements:

seta front A003
comp rear up

** Pressure based on rear
33, P1, 1.275000e+04
73, P1, 1.275000e+04
33, P6, 1.275000e+04

3

I tried

seta rear A008
comp rear up
seta front A003
comp front up

prnt se
prints f:0 still

seta rear A008
comp rear do
seta front A003
comp front do

prnt se
prints f:0 as well.

I do not get how comp works yet.

4

only
“prnt se”
and not
prints f:0

5

prnt se
1 all stat:o n:645 e:384 f:448 p:22 l:39 c:0 s:22 b:4 L:0 S:0 se:0 sh:0 v:1
3 beam stat:c n:645 e:384 f:448 p:22 l:39 c:0 s:22 b:4 L:0 S:0 se:0 sh:0 v:0
4 se0 stat:c n:3 e:0 f:0 p:0 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
5 se1 stat:c n:5 e:0 f:0 p:2 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
6 se2 stat:c n:5 e:0 f:0 p:2 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
7 ses1 stat:c n:9 e:0 f:4 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
8 ses2 stat:c n:25 e:0 f:0 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
9 ses3 stat:c n:25 e:0 f:0 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
10 ses4 stat:c n:25 e:0 f:16 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
11 ses5 stat:c n:9 e:0 f:4 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
12 ses6 stat:c n:25 e:0 f:16 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
13 rear stat:c n:9 e:0 f:0 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
14 front stat:c n:9 e:0 f:0 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
15 -NJBY stat:c n:0 e:0 f:0 p:0 l:0 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0

6

maybe these works:
“comp rear up”
and
“plot f rear”
at the end

7

this works
plus sa rear

all of your suggestions do not work on my site yet.

$ cgx --version
on a Linux machine, nodename bla-bla, release 5.15.0-56-generic, version #62-Ubuntu SMP Tue Nov 22 19:54:14 UTC 2022, machine x86_64
The HOME was detected:/home/bla
parameters:2 arguments:2
Version 2.17

8

One more thing

comp rear up
plus f rear
prnt se
1 all stat:o n:645 e:384 f:448 p:22 l:39 c:0 s:22 b:4 L:0 S:0 se:0 sh:0 v:1
3 beam stat:c n:645 e:384 f:448 p:22 l:39 c:0 s:22 b:4 L:0 S:0 se:0 sh:0 v:0
4 se0 stat:c n:3 e:0 f:0 p:0 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
5 se1 stat:c n:5 e:0 f:0 p:2 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
6 se2 stat:c n:5 e:0 f:0 p:2 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
7 ses1 stat:c n:9 e:0 f:4 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
8 ses2 stat:c n:25 e:0 f:0 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
9 ses3 stat:c n:25 e:0 f:0 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
10 ses4 stat:c n:25 e:0 f:16 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
11 ses5 stat:c n:9 e:0 f:4 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
12 ses6 stat:c n:25 e:0 f:16 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
13 rear stat:c n:99 e:192 f:0 p:0 l:0 c:0 s:1 b:2 L:0 S:0 se:0 sh:0 v:0
14 front stat:c n:9 e:0 f:0 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
15 -NJBY stat:c n:0 e:0 f:0 p:0 l:0 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
comp front up
prnt se
1 all stat:o n:645 e:384 f:448 p:22 l:39 c:0 s:22 b:4 L:0 S:0 se:0 sh:0 v:1
3 beam stat:c n:645 e:384 f:448 p:22 l:39 c:0 s:22 b:4 L:0 S:0 se:0 sh:0 v:0
4 se0 stat:c n:3 e:0 f:0 p:0 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
5 se1 stat:c n:5 e:0 f:0 p:2 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
6 se2 stat:c n:5 e:0 f:0 p:2 l:1 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0
7 ses1 stat:c n:9 e:0 f:4 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
8 ses2 stat:c n:25 e:0 f:0 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
9 ses3 stat:c n:25 e:0 f:0 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
10 ses4 stat:c n:25 e:0 f:16 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
11 ses5 stat:c n:9 e:0 f:4 p:0 l:0 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
12 ses6 stat:c n:25 e:0 f:16 p:4 l:4 c:0 s:1 b:0 L:0 S:0 se:0 sh:0 v:0
13 rear stat:c n:99 e:192 f:0 p:0 l:0 c:0 s:1 b:2 L:0 S:0 se:0 sh:0 v:0
14 front stat:c n:99 e:192 f:0 p:0 l:0 c:0 s:1 b:2 L:0 S:0 se:0 sh:0 v:0
15 -NJBY stat:c n:0 e:0 f:0 p:0 l:0 c:0 s:0 b:0 L:0 S:0 se:0 sh:0 v:0

comp front up adds 90 nodes, 192 elements and 2 bodies

9 
valu Etyp he8
seto beam
pnt p0 0 0 0
pnt p1 10 0 0

line l0 p0 p1
seta se0 l l0

swep se0 se1 tra 0 0 20
swep se1 se2 tra 0 0 40

seta ses1 A001
swep ses1 ses2 tra 0 4 0 2
swep ses2 ses3 tra 0 100 0 10
swep ses3 ses4 tra 0 4 0 2

seta ses5 A002
swep ses5 ses6 tra 0 108 0 10

seta rear A008
seta front A003
comp rear u
setc beam

elty beam Etyp
mesh beam
send beam abq

prnt se
send rear abq surf
send front abq surf
send rear abq spc 2
send rear abq pres 12750
send front abq pres 12750
plot f rear

image
image1283×650 47.1 KB

10

no way on my site

seta rear A008
seta front A003
comp rear u

setc beam

elty beam Etyp
mesh beam
send beam abq

view elem

send rear abq surf
send front abq surf
send rear abq spc 2
send rear abq pres 12750 # g/mm^2
send front abq pres 12750 # g/mm^2
plot f rear

11

Hello,

to apply dload inside volume elements is bit tricky.
If i remember right, there should be a post with these issue.

One Solution is maybe, that you delete the neighbour elements for selecting the faces
and then select by hand with command “qadd new f” and i as integer
or by hand like these

seta new e 33 43 53 63
seta new e 73 83 93 103
seta new e 113 123 133 143
seta new e 153 163 173 183
zap new

seta new e 42 52 62 72
seta new e 82 92 102 112
seta new e 122 132 142 152
seta new e 162 172 182 192
zap new

** Pressure based on rear
203, P3, 1.275000e+04
205, P3, 1.275000e+04
and so on

image
image534×631 2.87 KB

12

I left the idea with faces and come to the idea of applying force to nodes but I did not touch CalculiX for some time and it is not easy to do the input deck stuff to justify my idea right away.

valu Etyp he8
seto beam
pnt p0 0 0 0
pnt p1 10 0 0

line l0 p0 p1
seta se0 l l0

swep se0 se1 tra 0 0 20
swep se1 se2 tra 0 0 40

seta ses1 A001
swep ses1 ses2 tra 0 4 0 2
swep ses2 ses3 tra 0 100 0 10
swep ses3 ses4 tra 0 4 0 2

seta ses5 A002
swep ses5 ses6 tra 0 108 0 10

seta rear se ses3
seta front se ses2

setc beam

elty beam Etyp
mesh beam
send beam abq

send rear abq force 0 12000 0
send front abq force 0 -12000 0
send front abq spc 2

beam.inp

*HEADING
Model: CalculiX Beam Input File for internally applied force on nodes
*INCLUDE,INPUT=beam.msh
*BOUNDARY
*INCLUDE,INPUT=front_2.bou
*MATERIAL,NAME=EL
*ELASTIC
2e6, 0.3
*SOLID SECTION,ELSET=Ebeam,MATERIAL=EL
*STEP
*STATIC
*DLOAD
*INCLUDE,INPUT=rear.frc
** *NODE PRINT
** U
*NODE FILE ** It adds to Datasets → 1 DISP
U
*EL FILE ** It adds to Datasets → 2 STRESS
S
*END STEP

come up with

*ERROR reading *DLOAD. Card image:
112,2,12000.000000

where
112 name of the node
2 no idea what it is
12000.000000 load on the node

*CLOAD must be used instead of *DLOAD card in this case.

13

2 is the directon (degree of freedom) of the load force of the global or local coordinte system
what about *pre-tension section card?

wbr

14

*pre-tension section card

The parameter NODE is required as well as one of the parameters SURFACE and ELEMENT.
The latter two parameters are mutually exclusive.

In my case, it looks like, there is no SURFACE or ELEMENT parameter. No *pre-tension section card can be used. I appreciate if you show me otherwise.

15

Coordinate system
only x coordinate matches with drawing area while z and y are not.