Obsah

Semi-loofs, BEAM61G1

Problem

Stability of a column

Mesh

element type nodes
1 61 1 2 4 3 11 13 14 12 
2 61 3 4 6 5 14 16 17 15
3 61 5 6 8 7 17 19 20 18
4 61 7 8 10 9 20 22 23 21

Boundary conditions

$u=v=w=0$ at node 1
$u=w=0$ at nodes 2, 11
$v=w=0$ at node 9
$w=0$ at nodes 10 23

Computation

The unit end force is replaced with the equivalent edge traction as $$l_x=\frac{-1}{0.02}=-50\text{ N/m},\quad l_y=0\text{ N/m},\quad l_z=0\text{ N/m}.$$

The initial stress matrix is then computed from the stress field obtained by the standard linear analysis.

The computation is executed with the following commands:

beam61g1.bat
rmd3 beam61g1.i1
rpd3 beam61g1.i2
srh3 beam61g1.i3
fefs beam61g1.i4
geo3 beam61g1.iG
heig beam61g1.iE
stab beam61g1.iS

Input

beam61g1.i1
;  NELEM NNOD ITED
IP   4    23   61
;  CRIT SCALE THDEF
RP 1.01   1    0.01
XY N 1:10 X 2*0 2*0.25 2*0.5 2*0.75 2*1
          Y 5*(0 0.02)
          Z 10*0
EL E 1:4 N =A 1 2 4 3 =A =B 11 13 14 12 =B
           =2A =3B =4A =6B =6A =9B
EN
EN
beam61g1.i2
;  KREST
IP   1
         ; E    α ν   ρ
MP 1 T 1 V 2e11 0 0.3 0
LV 1 T 9 V -50 0 0 ; Fx = -1 N

AS 1 /M 1
  /B 0 N 1 /B 0 C 1 3 N 2 11      ; left end
  /B 0 C 2 3 N 9 /B 0 C 3 N 10 23 ; right end
  /L 1 E 4 L3

EN
EN
beam61g1.i3
;  KREST
IP   1
EN
EN
beam61g1.i4
;  KREST
IP   1
EN
EN
beam61g1.iG
;  ILC
IP  1
EN
EN
beam61g1.iE
;  KREST NROOT NITERX KTPR KEVP
IP   1     1      0     0    1
EN
EN
beam61g1.iS
IP 1
EN
EN

Output

beam61g1.oS
IP 1                                                                            
EN                                                                              
EN                                                                              


                              LOADING PARAMETERS
  0.329326E+04

                                * END OF STAB *
 TOTAL CPU: 00:00:00