Multiaxial

Multiaxial states of stress are very common in structures and components. We suggest that you review the constant amplitude section first if you are unfamiliar with the basic fatigue analysis methods and terminology. Fatigue is usually a surface phenomina so that the state of stress is biaxial because the stress normal to a free surface is zero. Biaxial loading includes states of stress where the individual components of stress and strain can be either in-phase or out-of-phase, sometimes called proportional and nonproportional loading. The multiaxial fatigue calculators are designed for evaluating these situations. Unlike uniaxial fatigue, there is no consensus as to the best fatigue damage model. Indeed it is unlikely that a single model will be applicable for all materials and states of stress and the multiaxial fatigue calculators will give estimates from more than one model.

Experienced user mode is off. Turn experienced user mode on for a more concise page.

Fatigue Calculators

  •  Stress-Life
    Use this method for constant amplitude multiaxial loading situations where all of the stresses and strains remain elastic.
  •  Strain-Life
    Use this method for constant amplitude multiaxial loading situations where plasticity around stress concentrations is important.

Fatigue Analyzers

Sign in or sign up to use these analyzers

  •  Variable Amplitude Stress-Life
    Use this method for variable amplitude multiaxial loading situations where all of the stresses and strains remain elastic.
  •  Variable Amplitude Strain-Life
    Use this method for variable amplitude multiaxial loading situations where plasticity around stress concentrations is important.

Finders

Technical Background