Hi
I am using ELLA to determine envelopes for a vehicle moving in lane, A. To use in further investigations i am extracting the position of the vehicle for highest and lowest section forces in a specific element. For some reason there are a big differences between the section forces found in the envelope, and the maximum and minimum forces for the specific element (see pictures below)
Why could there be this big difference?
Code used:
+prog sofiload urs:50.2
ECHO ACT
ACT L
ECHO LANE,LOAD
GAX ‘A’ S #lane X #Cx+0.5*#dlaneSC Y #Cy-#lane/2 Z 0 NX 0 NY 1 NZ 0 ! Axis A creation
LANE ‘A’ TYPE EN WR #dstradxP/2 WL -#dstradxP/2
LC 91 TYPE L TITL ‘Straddle carrier Lane 1’; TRAI USER DIR B DIRT B
TRPL 2*#Pstraddle PFAC 1 B #dstradxP
TRPL 2*#Pstraddle PFAC 1 DIST ABS #dstrady1P B #dstradxP
TRPL 2*#Pstraddle PFAC 1 DIST ABS #dstrady2P B #dstradxP
TRPL 2*#Pstraddle PFAC 1 DIST ABS #dstrady1P B #dstradxP
TRPL 2*#Pstraddle PFAC 1 DIST MIN 0.75 B #dstradxP
TRPL 2*#Pstraddle PFAC 1 DIST ABS #dstrady1P B #dstradxP
TRPL 2*#Pstraddle PFAC 1 DIST ABS #dstrady2P B #dstradxP
TRPL 2*#Pstraddle PFAC 1 DIST ABS #dstrady1P B #dstradxP
+PROG ELLA urs:6
HEAD EVALUATE WITH A TRANSVERSE INFLUENCE LINE
ECHO FULL YES
ECHO LPOS FULL
$SIZE -URS 0 HDIV 5
$SHOW AXIS.0 QUAD 5,14 ; ECHO IL 1+4
LSEL A.0 INT 5 B #dstradxP BWH #dstradxP
CALC MXX 1 2 SYST SPAC ! Max/Min MXX envelope saved as 101/102
CALC MYY 3 4 SYST SPAC ! Max/Min MYY envelope saved as 103/104
CALC VXX 7 8 SYST SPAC ! Max/Min VXX envelope saved as 107/108
CALC VYY 9 10 SYST SPAC ! Max/Min VYY envelope saved as 109/110
CALC NXX 11 12 SYST SPAC ! Max/Min NXX envelope saved as 111/112
CALC NYY 13 14 SYST SPAC ! Max/Min NYY envelope saved as 113/114
SAVE 100 TITL ‘transverse’ ! Base for saving of load cases
CASE 1 GR1 ! Case 1 is defined as a gravity load GR1
POSL A.0 91 P 0.0 ! In lane A loadcase 91 (LM71) is placed
COMB A0 L1 1.00 F1 1.00
sto#MAMI ‘MAX’, ‘MIN’, ‘MAX’, ‘MIN’, ‘MAX’, ‘MIN’, ‘MAX’, ‘MIN’, ‘MAX’, ‘MIN’, ‘MAX’, ‘MIN’,
sto#SF ‘MXX’, ‘MXX’, ‘MYY’, ‘MYY’, ‘VX’, ‘VX’, ‘VY’, ‘VY’, ‘NXX’, ‘NXX’, ‘NYY’, ‘NYY’
sto#SFnr 1, 2, 3, 4, 7, 8, 9, 10, 11, 12, 13, 14
END
+prog sofiload urs:63.1
head Extract moving load positions
! LC 999/1000 MAX/MIN MXX
lc no 999 type none
copy no 101 fact 1.0 type ella ref A.0 case 1 nre 101751
lc no 1000 type none
copy no 102 fact 1.0 type ella ref A.0 case 1 nre 101751
end
PROG ASE urs:4
HEAD LINEAR LOAD CASE
LC 999 ! ASE linear calculation with only train load
LC 1000 ! ASE linear calculation with only train load
END