Different Results

Question:

Hi all,

you find 2 model on attached, the difference is dimension of mesh, but results are about 50% differets, please let me know your opinion

thnaks

regards



Answer:

Hello,

Due to mesh size, there can be minor difference.  But generally when the difference is very high for time history analysis, it due to improper time history load case definition.  It was noted that the time loading function has least time duration in multiple of 0.0001 sec, while the time history load case had a time increment of 0.01 sec.  This would lead to an impact sort of loading on the structure when the loading suddenly appears at a node.  To avoid this, just increase the time increment to 0.0001 sec in the time history load case as indicated in the image below.


It could be noted that on making the change as indicated in the image above, the difference in result is negligible.  The modified model wherein this has been done just for one case have been attached for your review.  Kindly let us know if further assistance would be required.

Regards,
Nandeep
Technical Manager, MIDAS
Creation date: 10/17/2018 9:16 PM (dklee@midasit.com)      Updated: 10/18/2018 6:47 AM (dklee@midasit.com)
Files   
16+815.zip
16+815_mesh 0.25.mcb
16+815_mesh 0.37.mcb
DataImage69.png
Difference results.pptx