Keyword expand in PFC tutorial

Hey everyone,

In the code ‘MakeSpecimen.dat’ of the PFC tutorial “Probing a Granular Sepcimen” I noticed the word ‘expand’. When using the search function, I couldn’t find its meaing. Can somebody help me out?
Thank you in advance!


Dear Nick,
it seems like we missed the keyword “expand” in the documentation. Thank you for making us aware of that!
What the keyword does is fairly simple: It expands the created walls by the value that you specify. See the two figures below for better understanding.

Figure 1: Using: wall generate name ‘vessel’ box -0.035 0.035 expand 1.5

Figure 2: Using: wall generate name ‘vessel’ box -0.035 0.035

1 Like

Hello Nick, I’m Jane. Would you mind to tell me how to post a question in this forum? I can’t find the post button in this website, but I can reply other people’s question posts. Thank you in advance.

Dear Jane,
you can create a new post by clicking on the “New Topic” button in the top right corner of the form-homepage: Itasca Software Forum - Let’s help each other (

If you can not see that button you probably have not provided a license during your registration. As explained in the “Welcome to Discourse”-Post ( Welcome to Discourse - Itasca Software Forum ( you need a valid software license do post any questions. You can add a license to your account in the “Profile” tab of your accounts preferences.