PROCEDURE TO PREDICT ULTIMATE FRACTURE FAILURE HISTORY FOR PLANE-STRESS PLASTICITY PROBLEMS

A finite element solution procedure is presented to predict the load-displacement history up to ultimate fracture failure for a structural system. Incremental plasticity theory for the von Mises yield criterion and isotropic strain hardening are used to march along the uniaxial stress-strain curve of the material up to fracture. When an element fractures its strain energy is distributed into the unfractured elements using an element nodal release method. If another element fractures during this redistribution process, then unstable crack growth is said to occur, and the total load at this stage is termed the ultimate fracture failure load of the structural system. The analysis steps to automate the solution procedure are described. Numerical results obtained for a center pre-cracked panel tension specimen are reported and compared with experimental results available in the literature.