Peridynamics Tensil test with LAMMPS

Hi everyone.

I am trying to do a tensile test on Ti metal in peri dynamics and calculate the stress and strain amounts. but I couldn’t get good and expected results! I applied the “move” fix command to the top region of box and the bottom is fixed. my approach is to calculate the stress and strain in the same way I did before in MD simulation. my LAMMPS input file was attached.

I am using “Microsoft Windows [Version 10.0.22621.2134]” LAMMPS.
my simulation box is 0.0030.0060.003 m and 2000 particles included in the box.
It will be appreciated if you could help me to figure out what is the problem with my code.
thank you,
pd.txt (3.8 KB)

I have 0 knowledge on peridynamics, but

obviously this is not the lammps version but rather the Windows version :slight_smile:

my bad!! thanks for your attention

Sorry, but it is not likely that somebody here will want to spend time to explain your research to you. Please keep in mind, that LAMMPS will perform the simulation with the parameters and settings that you feed it. So what you get as a result is a consequence of your input. If the consequence is not what you expect, then either your input is not suitable or your expectations are not correct. In both cases, this is something you need to discuss with somebody that is familiar with your research. There is no “magic” switch that will make any LAMMPS input go from “bad” to “good”. You will have to go back and review every little bit of input that you enter and check if this is suitable.

Thanks for your reply.
I studied a lot of papers, thesis and input files of LAMMPS and did some successful modelling in MD, but in PD I have some issues with using LAMMPS.
There are many examples in fracture or indentation problems, but I couldn’t find any useful resources to help me to do tensile test. I don’t have any problem with the concepts of peridynamics, and tried many ways to modify my input file but I have faced with many errors and unexpected results.
I already have the PD modelling results in MATLAB, but I really want to tack same with LAMMPS! I calculated my PMB parameters with considering the rotation effects and I don’t think that it is my script problem!
I don’t expect someone to solve my problem, but maybe just a suggestion or experience in this way, can be helpful! what is common in this forum.

To get helpful advice you are not providing specific enough information. All you are saying is: here is my input. I don’t get the results I expect. What you don’t say is what you do expect and why you do expect this. You don’t say what your system should represent, where exactly and how exactly you derived the parameters. How you did the MD simulations you are talking about and how specifically those were similar or different from your PD run. You say you have computed the same in MATLAB, but how can we know that is correct? How do you know?
Bottom line, unless somebody is an expert in peridynamics and knows about your level of experience and skill and knows what your research project is about specifically and what you have done so far, it is next to impossible to help you. Or one would need to be a long-distance mind reader…