On damage diagnostics of aircraft structures

Methods of evaluation of damage in constructions are discussed on the example of specimen’s tests under loading programs of aircraft structures in operation. The appearing damages in the form of cracks, causing the increase of displacements of specimens, testify to the degree of damage of a structural component. By estimating the rate of increase of displacements, one can estimate the approach to the final fracture of this component. The same can be done by measuring the inelastic behavior of the structure associated with the damage. The difference in displacement during loading and unloading is a sensitive measure in the assessment of structure’s damage.