Polymeric materials often have the topological transformation such as the fracture, but the simulation of these systems is difficult for the nonlinearity and the topological exchange. We perform FEM fracture simulations using a Delaunay triangular lattice in the Eulerian-Lagrangian pictures. We calculated the stress, the diverged stress profile around the edge, andJ⁁-integral using a virtual crack extension method in our simulator. Then we introduce the crack generation and evolution on the multi droplet system and the gel shrinking system. ©2000 American Institute of Physics.