Finite element and experimental analyses of fatigue crack closure for structural steel

Crack closure levels derived from the finite element analysis and from the local compliance measurements for structural steel are compared. It is shown that the observed crack opening stress values fall in between the numerical results obtained assuming the plane strain conditions and the plane stress conditions at the crack tip. The present work implies that the finite element model, once properly validated through high accuracy crack closure measurements, can be applied to calibrate the strip-yield type crack growth prediction models.