Analyzing the relationship between strain and displacement in a beam model

- May 24, 2024 at 12:15 pm
  
  Jannick
  Subscriber
  
  Hello everyone, I need some assistance with LS-Dyna. I am currently working on a beam model and I am interested in understanding how the strain of each element relates to the overall displacement. I can already generate curves for stress over time using history - elements. I extract the displacement data through an ASCII-nodout. Normally, I would create an XY plot and cross-reference these values, but this is not possible with stress data. My goal is to create a histogram in python that shows x% of the values are within a range of x-x at a displacement of x mm. Is there perhaps a better method to achieve this? Thank you in advance for your help.
- May 31, 2024 at 2:02 am
  
  Ushnish Basu
  Ansys Employee
  
  For integrated beams, you can get axial strain at beam integration points by setting BEAMIP (*database_extent_binary) to the number of beam integration points. Then, after running the model, read d3plot into LS-PrePost and click History > Int.Pt. > Etype: Beams > (click on any beam element) > Axial Strain > Plot.
- June 5, 2024 at 12:07 pm
  
  Jannick
  Subscriber
  
  Thank you for your feedback. Unfortunately, I use Shell Elements for my simulation, so the beam Elements does not work. What I have found out. I can add a history database and save the elout. The file contains the strain in xx,yy,zz and xy,yz and zx. Can I somehow calculate plastic strain from this using a formula? Unfortunately, I have not found anything suitable.
- July 5, 2024 at 9:56 pm
  
  Ushnish Basu
  Ansys Employee
  
  The plastic strain is actually a stress-related quantity (see https://lsdyna.ansys.com/radial-return/), and is available in elout along with the stresses