Performance Alarming for Stay Cables Based on a Frequency–Deformation Relationship Model

Stay cables are vital load-bearing components of cable-stayed bridges that are prone to corrosion and fatigue. Damaged or deteriorated cables can endanger the safety of bridges. In this paper, a performance alarming method for stay cables based on a frequency–deformation relationship (FDR) model is proposed. First, the FDR model, which represents a normal relationship between the frequency and the deformation of a certain intact cable, was established according to the stress–strain relationship of the cable. Second, the performance alarming for a stay cable was realized by constructing a mean value control chart for the estimation error of the baseline FDR model, followed by an implementation procedure for the early warning method. Last, the long-term monitoring data of a large-span bridge are utilized to validate the effectiveness of the performance alarming method. The results demonstrate that the modeling and prediction capabilities of the proposed FDR model are satisfactory and that the performance alarming for stay cables can be carried out effectively by the proposed method.