Patent ID: 8606532

Claim:
A fracture determination method for determining a fracture of a metal structure, the method comprising: a deformation analyzing step of performing deformation analysis from start of deformation to end of deformation of the metal structure; and a fracture determination step of extracting a fracture determination target portion from a deformation state of the metal structure obtained in the deformation analyzing step, and when the extracted fracture determination target portion has returned from a plastic state to an elastic state, given that a stress when the portion returned to the elastic state is (x, y)=(σ 2 , σ 1 ) (maximum principal stress: σ 1 , minimum principal stress: σ 2 ) on a (x, y) coordinate plane, performing fracture determination of the fracture determination target portion using a re-yield stress determined by an intersection between a straight line satisfying a relation y=(σ 1 /σ 2 )x and an yield curve obtained from the plastic state of the fracture determination target portion.