Stability of a column

BEAM6—four quadrilaterals

$u=v=0$ at node 11
$v=0$ at node 23

The unit end force is replaced with the equivalent surface traction as $$q_x=\frac{-1}{0.01\times 0.02}=-5000\text{ Pa},\quad q_y=0\text{ Pa}.$$

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

beam56g2.bat

rmd2 beam6g2.i1
rpd2 beam6g2.i2
srh2 beam6g2.i3
fefs beam6g2.i4
geo2 beam6g2.iG
heig beam6g2.iE
stab beam6g2.iS

beam6g2.i1

;  NELEM NNOD ITED  ...  KSS
IP   4    23    6   6*0  -1
;  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)
EL E 1:4 N =A 1 3 4 2 =A =B 12 14 13 11 =B
           =2A =3B =4A =6B =6A =9B
EN
EN

beam6g2.i2

;  KREST
IP   1
         ; E    α ν   ρ
MP 1 T 1 V 2e11 0 0.3 0
SV 1 T 9 V -5000 0 0 ; Fx = -1 N

AS 1 /M 1
  /B 0 N 11 /B 0 C 2 N 23
  /S 1 E 4 S1

EN
EN

beam6g2.i3

;  KREST
IP   1
EN
EN

beam6g2.i4

;  KREST
IP   1
EN
EN

beam6g2.iG

;  ILC
IP  1
EN
EN

beam6g2.iE

;  KREST NROOT NITERX KTPR KEVP
IP   1     1      0     0    1
EN
EN

beam6g2.iS

IP 1
EN
EN

beam6g2.oS

IP 1                                                                            
EN                                                                              
EN                                                                              


                              LOADING PARAMETERS
  0.139941E+04

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