Nonzero traction error in spontaneous rupture model


I have modified step13 in hex8 (slip-weakening fault friction in a quasistatic problem) to build a spontaneous rupture model for my own fault. I have encountered an error regarding the tractions on the fault. The fault is planar with a fine mesh. Here’s what pylith is returning:

“terminating with uncaught exception of type std::runtime_error: WARNING! Fault opening with nonzero traction., v_fault: 1735, opening: 9.60479e-07, normal traction: -1.05722e-05”

I tried attaching the json file but I get an error saying “new users cannot upload attachments”. I can provide it via email if that would help solve the problem.

Thank you,


You need to adjust the solver tolerances. See the discussion of solver tolerances in the slides of the 2017 CDM tutorial 2-D Subduction Zone: Fault Friction.

Thank you, Brad.

I have tried using the tolerances recommended in the slides but continue to get the same error. I have also tried increasing the tolerances while respecting the suggestions in the tutorial (keeping ksp_atol and snes atol larger than zero_tolerance) with no luck. Increasing the tolerance of the zero_tolerance_normal to 10^-3 made it crash much later, yet it still ultimately brought up the same error.

Thank you for your help,