Error: Property pb_radius of contact model linearpbond is read only!

PFC
1

Hello everyone,

I am trying to assign the following parallel bond properties in PFC3D:

contact property pb_ten 2.111e4 pb_coh 3.0e3 pb_fa 35 pb_rmul 2.5 pb_r 0.5

However, I receive the following error:

*** Property pb_radius of contact model linearpbond is read only!
While processing line 210 of source triaxial new.dat in Editor.

My questions are:

  1. Why is pb_radius (pb_r) a read-only property?

  2. Is the bond radius supposed to be controlled only through pb_rmul (radius multiplier), or is there another method to specify the bond radius?

  3. If I want to define a bond radius equal to 0.5 times the minimum particle radius, what is the correct approach?

  4. Has the syntax for setting the bond radius changed in recent versions of PFC3D?

I am using the Linear Parallel Bond contact model and would appreciate any guidance on the correct way to define the bond radius.

Thank you in advance for your help.

2

Thank you for your use of PFC. Here follow my replies to your four questions. (1) It is read-only because to set it you must use the property pb_rmul (e.g., {contact property pb_rmul 0.7}); (2) yes, see item 1; (3) write a FISH function to loop over all contacts, then select those that have the pbond contact model, determine the desired radius by checking the radii of the two balls at the contact (use FISH functions contact.end1() and contact.end2()), then assign the value with FISH function contact.prop() {contact.prop(cp, ‘pb_rmul’) = 0.7}; (4) no.