fracture mechanics and crack growth using ansys 12.1 workbench n-code

      i am a student of 4th year mechanical engineering.

     i working on  project of fracture mechanics. in this project we consider flat square plate with a central hole having specified dimenstion and material. initially we assume symmetric crack around a hole. i want to find out crack growth under different tensile load condition and using this i want to find out stress intensity factor and  when it reaches to cataschrophic failure. plz give ans as soon as possible