$u=v=0$ at node 11
$v=0$ at node 27
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.
rmd2 beam4g2.i1 rpd2 beam4g2.i2 srh2 beam4g2.i3 fefs beam4g2.i4 geo2 beam4g2.iG heig beam4g2.iE stab beam4g2.iS
; NELEM NNOD ITED ... KSS IP 8 27 4 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 1:8 N =P 1 3 2 =P =Q 12 13 11 =Q =R 3 4 2 =R =S 15 14 13 =S =2P =4Q =2R =4S =4P =8Q =4R =8S =6P =12Q =6R =12S EN EN
; 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 27 /S 1 E 8 S2 EN EN
; KREST IP 1 EN EN
; KREST IP 1 EN EN
; ILC IP 1 EN EN
; KREST NROOT NITERX KTPR KEVP IP 1 1 0 0 1 EN EN
IP 1 EN EN
IP 1 EN EN LOADING PARAMETERS 0.140350E+04 * END OF STAB * TOTAL CPU: 00:00:00