Damage detection through bilinear stiffness estimation in multi-degree-of-freedom frame structures

GARRIDO HERNÁN; CURADELLI, OSCAR

International Journal of Lifecycle Performance Engineering

Inderscience Enterprises Ltd

Lugar: Reino Unido; Año: 2014 vol. 1 p. 380 - 397

During its lifetime, the integrity of structures may be affected byexposure to dynamic loads such as earthquakes. In these cases, structures mightbecome damaged, and an early overall evaluation of their integrity is necessary.A particular pattern of damage is that produced by the existence of breathingcracks. These cracks are characterised by their opening and closure during theoscillation of the cracked structural element. In this paper, it is proposed amethod for detection of breathing cracks in multi-degree-of-freedom framestructures. The method is based on bilinear stiffness direct estimation,individually for each story of the structure, by using a least-squares approach.The proposed method is demonstrated through a numerical example using theFEM to model a planar structure which presents several breathing cracks. Theresults suggest that this approach is more sensitive and precise than approachesbased on linear stiffness models in detecting and localising damage due tobreathing cracks.