# Structural modification and consideration of factors

**URL:** <https://community.dlubal.com/t/strukturmodifikation-und-berucksichtigung-von-faktoren/5526>\
**Category:** Product Support\
**Tags:** structure-modification, rfem-6\
**Created:** [November 4, 2026, 6:16am UTC](https://community.dlubal.com/t/strukturmodifikation-und-berucksichtigung-von-faktoren/5526 "2026-11-04T06:16:25Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Andreas1705](https://community.dlubal.com/letter_avatar_proxy/v4/letter/a/ee59a6/32.png) [@Andreas1705](https://community.dlubal.com/u/Andreas1705)\
**Post date:** [November 4, 2026, 6:16am UTC](https://community.dlubal.com/t/strukturmodifikation-und-berucksichtigung-von-faktoren/5526/1 "2026-11-04T06:16:25Z")

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As part of my master's thesis, I am using the student version of Dlubal RFEM 6. I have noticed that the stiffness modification does not appear to work as expected.  
When I multiply the stiffness by a factor of 0.5 using the stiffness modification, it is actually multiplied by a factor of 0.25.  
A simple comparison calculation for a fixed-ended bar confirmed this behavior: reducing the stiffness by a factor of 0.5 results in four times the deformation instead of the expected double the deformation.  
Could you please look into this and let me know whether it might be a bug, or whether I may be overlooking something in how I enter or apply the stiffness modification?

Thank you in advance.

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**Author:** ![marco.nikoleizig](https://community.dlubal.com/user_avatar/community.dlubal.com/marco.nikoleizig/32/102_2.png) [@marco.nikoleizig](https://community.dlubal.com/u/marco.nikoleizig)\
**Post date:** [November 4, 2026, 8:46am UTC](https://community.dlubal.com/t/strukturmodifikation-und-berucksichtigung-von-faktoren/5526/3 "2026-11-04T08:46:48Z")

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Hi Andreas1705,

Thanks for your message!

To analyze the problem more closely, the **model file** would be very helpful:

➡ Click _File_ → _Save As_ and choose the following settings to reduce the file size:

 ![image](https://community.dlubal.com/uploads/default/original/1X/8b1a4d47ea10737b559f12b01985d0ad3b4a8096.png)

➡ Then upload the file here (e.g. \*.rf6, \*.rs9) so the community can help find a solution too.

🦉 Would you rather not share the file publicly? No problem — send it to me in a direct message: click my _profile picture_ or _username_ → _Message_.

Best,  
Marco Nikoleizig

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**Author:** ![Andreas1705](https://community.dlubal.com/letter_avatar_proxy/v4/letter/a/ee59a6/32.png) [@Andreas1705](https://community.dlubal.com/u/Andreas1705)\
**Post date:** [November 4, 2026, 8:58am UTC](https://community.dlubal.com/t/strukturmodifikation-und-berucksichtigung-von-faktoren/5526/4 "2026-11-04T08:58:46Z")

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[Test Structure Modification.rf6](https://community.dlubal.com/uploads/short-url/9gwFMlsN6gd3xIAI1xTwx1orPvP.rf6) (1.1 MB)

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<div class="post-metadata">

**Author:** ![marco.nikoleizig](https://community.dlubal.com/user_avatar/community.dlubal.com/marco.nikoleizig/32/102_2.png) [@marco.nikoleizig](https://community.dlubal.com/u/marco.nikoleizig)\
**Post date:** [November 4, 2026, 1:31pm UTC](https://community.dlubal.com/t/strukturmodifikation-und-berucksichtigung-von-faktoren/5526/5 "2026-11-04T13:31:42Z")

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Hi Andreas1705,

The effect you describe is exactly right. In the structural modification, the checkbox for Gamma\_M1 is selected. This gamma value is read from the material properties. You had also set k = 0.50 here, as shown in the image:

 ![image](https://community.dlubal.com/uploads/default/original/2X/1/12b883f09ffb7f55d26922a7d94a37755a618abe.png)

Solution: Either disable Gamma\_M1 in the structural modification or set k = 1.0 in the material.

Best regards,  
Marco Nikoleizig