split interface 45 into a and b to avoid rogue dof

...soil_with_inner_patch-realistic-different-model-change.py

.../TP-TP-layered_soil_with_inner_patch-realistic-pure-dd.py

.../Archive/TP-TP-layered_soil_with_inner_patch-realistic.py

...e-with-inner-patch/TP-TP-layered_soil_with_inner_patch.py

...nner_patch-realistic-different-model-change_mesh_study.py

...red_soil_with_inner_patch-realistic-pure-dd_mesh_study.py

...h_study/TP-TP-layered_soil_with_inner_patch_mesh_study.py