Non-probabilistic interval identification method for structural damage

An interval damage-identification method for a structural system with uncertainties in the excitation force and measurements is proposed based on the acceleration responses of structural time-domain. The uncertainties were considered as bounded interval numbers. Based on the referencial finite element model and the measured acceleration response, the interval models for undamaged and damaged structures were obtained by the proposed two-step interval updating procedure. Then, the possibility of damage existence (PoDE) was defined to estimate the damage possibility of each element. A 10-bar truss structure is employed for the damage identification calculation, and the damage identification results obtained by the interval analysis method and probabilistic method, respectively, were compared with each other, and the effects on the detection results of the damage level and uncertain level were discussed in detail. Numerical example illustrates the feasibility and the validity of the proposed method.