*HEADING Test for loading/unloading/perturbation/reloading - COH3D8, Explicit *NODE 1,0.0,0.0,1.0 2,1.0,0.0,1.0 3,1.0,0.0,0.0 4,0.0,0.0,0.0 5,0.0,1.0,1.0 6,1.0,1.0,1.0 7,1.0,1.0,0.0 8,0.0,1.0,0.0 11,1.25,1.25,2.25 12,2.25,1.25,2.25 13,2.25,1.25,1.25 14,1.25,1.25,1.25 15,1.25,2.25,2.25 16,2.25,2.25,2.25 17,2.25,2.25,1.25 18,1.25,2.25,1.25 *NSET,NSET=FRONT1 2,3,7,6 *NSET,NSET=BACK1 1,4,8,5 *NSET,NSET=FRONT2 12,13,17,16 *NSET,NSET=BACK2 11,14,18,15 *NSET,NSET=QA_TEST FRONT1,BACK1,FRONT2,BACK2 *nset,nset=qa_test_axial 2, *nset,nset=qa_test_shear 12, *ELEMENT,TYPE=COH3D8,ELSET=ALL 1,1,2,3,4,5,6,7,8 11,11,12,13,14,15,16,17,18 *elset,elset=qa_test_axial 1, *elset,elset=qa_test_shear 11, **SOLID SECTION, ELSET=ALL, MATERIAL=STEEL *COHESIVE SECTION,elset=all,material=steel,thickness=geometry,stack direction=1,response=traction separation,controls=contr *section controls, name=contr,element deletion=no *MATERIAL, NAME=STEEL *ELASTIC,type=traction **,, 1.0E6,1.0E6,1.0E6 *DAMAGE INITIATION,CRITERION=QUADS **, , 61.0,68.0,68.0 *DAMAGE EVOLUTION,TYPE=ENERGY,MIXED MODE BEHAVIOR=BK,POWER=1.45 **,, 0.075, 0.60,0.60 *DENSITY 100.0, *amplitude,name=amp1,definition=smoothstep 0.0,0.0,1.0,1.0 *amplitude,name=amp2,definition=smoothstep 0.0,1.0,1.0,0.0 ********************* ** Step 1 - Loading ********************* *STep *dynamic,explicit,direct 0.001,1.0 ** apply boundary conditions *BOUNDARY,amplitude=amp1 ** loading of element 1 (axial stretch) ** **displacement at mode I damage initiation: (ultI)/(Emod) = 6.1E-05 **displacement at full damage=2*GIc/(ultI)=0.002459 FRONT1,1,1,0.00075 FRONT1,2,3,0.0 BACK1,1,1,-0.00075 BACK1,2,3,0.0 ** loading of element 2 (shear deformation) ** **displacement at mode II damage initiation: (ultII)/(Emod) = 6.8E-05 **displacement at full damage=2*GIIc/(ultII)=0.017647 FRONT2,1,1,0.0 FRONT2,2,2,0.0045 FRONT2,3,3,0.0 BACK2,1,1,0.0 BACK2,2,2,-0.0045 BACK2,3,3,0.0 *********************** *OUTPUT, FIELD,num=5,var=preselect,timemarks=yes *output,field,num=1 *node output,nset=qa_test_axial u, *node output,nset=qa_test_shear u, *OUTPUT,HISTORY,timeint=0.005 *node output,nset=qa_test_axial u1, *element output,elset=qa_test_axial s33, *node output,nset=qa_test_shear u2, *element output,elset=qa_test_shear s23, *ENERGY OUTPUT,VAR=PRESELECT *END STEP ********************* **Step 2 - Unloading ********************** *STep *dynamic,explicit,direct 0.001,1.0 ** apply boundary conditions *boundary,amplitude=amp2 FRONT1,1,1,0.00075 FRONT1,2,3,0.0 BACK1,1,1,-0.00075 BACK1,2,3,0.0 ** loading of element 2 (shear deformation) ** **displacement at mode II damage initiation: (ultII)/(Emod) = 6.8E-05 **displacement at full damage=2*GIIc/(ultII)=0.017647 FRONT2,1,1,0.0 FRONT2,2,2,0.0045 FRONT2,3,3,0.0 BACK2,1,1,0.0 BACK2,2,2,-0.0045 BACK2,3,3,0.0 *END STEP *********************** **Step 4 - Reoading *********************** *STep *dynamic,explicit,direct 0.001,1.0 ** apply boundary conditions *BOUNDARY,amplitude=amp1 ** loading of element 1 (axial stretch) ** **displacement at mode I damage initiation: (ultI)/(Emod) = 6.1E-05 **displacement at full damage=2*GIc/(ultI)=0.002459 FRONT1,1,1,0.00150 FRONT1,2,3,0.0 BACK1,1,1,-0.00150 BACK1,2,3,0.0 ** loading of element 2 (shear deformation) ** **displacement at mode II damage initiation: (ultII)/(Emod) = 6.8E-05 **displacement at full damage=2*GIIc/(ultII)=0.017647 FRONT2,1,1,0.00 FRONT2,2,2,0.0090 FRONT2,3,3,0.0 BACK2,1,1,0.0 BACK2,2,2,-0.0090 BACK2,3,3,0.0 *END STEP ********************************* **Step 5 - Unloading ***************************** *STep *dynamic,explicit,direct 0.001,1.0 ** apply boundary conditions *boundary,amplitude=amp2 FRONT1,1,1,0.00150 FRONT1,2,3,0.0 BACK1,1,1,-0.00150 BACK1,2,3,0.0 ** loading of element 2 (shear deformation) ** **displacement at mode II damage initiation: (ultII)/(Emod) = 6.8E-05 **displacement at full damage=2*GIIc/(ultII)=0.017647 FRONT2,1,1,0.0 FRONT2,2,2,0.0090 FRONT2,3,3,0.0 BACK2,1,1,0.0 BACK2,2,2,-0.0090 BACK2,3,3,0.0 *END STEP *********************************** **Step 6 - Reloading in compression ********************************* *STep *dynamic,explicit,direct 0.001,1.0 ** apply boundary conditions *BOUNDARY,amplitude=amp1 ** loading of element 1 (axial stretch) ** **displacement at mode I damage initiation: (ultI)/(Emod) = 6.1E-05 **displacement at full damage=2*GIc/(ultI)=0.002459 FRONT1,1,1,-0.000150 FRONT1,2,3,0.0 BACK1,1,1,0.000150 BACK1,2,3,0.0 *END STEP