Structural damage localisation based on generalised flexibility change rate curvature and data fusion technology

Damage localisation is the key to structural damage identification. Based on the study of damage index using the flexibility method, this paper presents a damage localisation index using the generalised flexibility matrix before and after structural damage. To enhance the accuracy of structural damage localisation, it is necessary to improve the sensitivity of damage index. Therefore, this paper puts forward a generalised flexibility change rate curvature index with the objective of improving the accuracy in localising structural damage. The curvature index is defined as the second-order difference of the generalised flexibility change before and after damage. Consequently, the curvature-based index usually is more sensitive to structural damages. To enhance the accuracy and efficiency of multiple damage localisation, the generalised flexibility change rate curvature index is combined with data fusion technology based on Dempster-Shafer’s theory. Numerical simulations and experimental studies have validated the capability and efficiency of the proposed method for damage localisation also in the case of multiple damages, noise impact, and limited modal orders.