Learning Forum

[TAOUFIK]

Hi

I try to apply a moving load (=10^8N) on on a bridge model using transient analysis, but i get very different results compared to statical analysis

I think the problem is related to the time increment and the number of substeps parameters

 

[Ashish Khemka]

Hello,

Can you elaborate on how the results are different? What were you expecting? If you leave out the transient part from the response of transient analysis then do you see similarity in steady state portion of the response when compared with static analysis results?

Regards,

Ashish Khemka

[TAOUFIK]

i would first to thank your for your reply ,

In fact, i have applied the moving load on the named selection "noeuds hourdis" that contains 2240 nodes using different values of end time and time increment, but results of deformation of the deck were very lower (0.002m) than those of the statical analysis (3.44m)

So i think that the force is not correctly applied on the different nodes !

Please could you explain how to set these parameters in this case

 

[Ashish Khemka]

Can you share snapsjot of how you applied the forces in both analysis types?

Regards,

Ashish Khemka

[TAOUFIK]

statical

transient

Regards

[TAOUFIK]

Could any one help please?

[Ashish Khemka]

Hi,

What is the duration of tranisent analysis, what is the maximum value of above function during the analysis? Also, check for large deflection effects - are they on in both the analysis (static and transient)?

It would be difficult to comment further without looking into the model. Ansys employees cannot look into the model. Do you have access to Ansys Support? If yes then you raise a support case.

Regards,

Ashish Khemka

[TAOUFIK]

Hi Ashish

My question is how to choose the duration of tranisent analysis and time step in order that the load (=10^8N) be applied on all nodes

the load function depends on the time step

large deflection effects are off for both analysis

Thanks

[Ashish Khemka]

Hi,

End time is something to be decided by the user. For a sample, I tried following data points and see that force increases with time for location x=0:

You should have large deflections turned on in both the analysis system.

Regards,

Ashish Khemka

[TAOUFIK]

Thanks

My problem is solved, i deactivate the option 'divide load by nodes' so i have the same results

Regards