[Bug Report] Axis Variable doesn't work at all?

SOFiSTiK Teddy
#1

First of all, here is the Teddy .dat file link: three span box girder bridge.dat (4.8 KB)

Basiclly it’s a 3-span concrete single box with two cells girder bridge.

The cross section has 26 independent variables, like ‘H’ - box total height, ‘Wt’ - top slab width, ‘Tt’ - top slab thickness, etc

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The cross section also has 38 derived variables.

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The cross section can be drived by previous mention 26 independent variables,
e.g. H=1.5m 1

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H=3.0m 1

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I create an axis variable H (box height) in SofimshC

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the result looks correct to me
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BUT, the generated bridge has constant sections, NO variation along the axis

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#2

I find the reason why axis variable doesn’t work: If you use derived variable, then axis variable is not able to work.

I strongly suggest Sofstik allowing derived variable, cause derived variable will make defining parameterized cross section more convenient.

#3

Hello,

First: It is possible to use derived variables.

These variables have to marked as variables in the formulas with a #: e.g. Yrt ‘=0.5*#Wt-#Wf’

Regarding the second issue with the variable H in SOFiMSHC (or in SOFiPLUS): For an interpolation of the cross section, it is necessary to set the reference on the axis. If only the structural lines are input in SOFiMSC (or in SOFiPLUS) no interpolation of the cross section is done.

If the problems persist, please contact support@sofistik.com and send the input file.

With kind regards
Sabine Fahrendholz
Product Management

#4

Hello Sabine,

I know that derived variable can work. But if derived variable works together with axis variable, then the axis variable will NOT work.

E.g.
I want to define an Axis Variable “H”, which is the height of a rectangule section.

I find that if the vertices of the section doesn’t EXPLICITLY includes “H”， then the Axis Variable “H” doesn’t work.

I define such section as below
TVAR ‘B’ 1
TVAR ‘H’ 1
TVAR ‘a’ ‘=#H+1-1’ $ derived variable

POLY    TYPE    MNO
    O   1
VERT    NO  Y   Z   REFP
    0   0   0
    1   '=#B/2' 0   0
    2   0   '=-#a'  1
    3   '=-#B'  0   2
    4   0   '=#a'   3
END

Although ‘a’ equals to ‘H’ mathematically (TVAR ‘a’ ‘=#H+1-1’), the Axis Variable “H” doesn’t work, because ‘a’ doesn’t EXPLICITLY includes ‘H’

Teddy dat file is attached.
1.dat (1.8 KB)