Comprehensive Evaluation of Elasto-Magnetic Parameters for High-Performance Cable Force Monitoring Under the Effect of Temperature

The elasto-magnetic (EM) method is a promising pathway for cable force monitoring in cable-stayed bridges. The cable-stayed bridges are usually installed outdoors experiencing daily variations in temperatures, which is believed to have a noticeable influence on EM signal. In this study, EM calibration experiments were performed on a seven-wire steel strand to measure the variation in the main flux. Comprehensive indicators considering sensitivity, hysteresis error, and cable force resolution were used to examine the performances of classic EM parameters and new candidate ones. Seven parameters picked up by the comprehensive indicator were further compared in experiments considering both the effects of force and temperature. Through comparative study, two new parameters demonstrated outstanding ability for both cable force measurement and temperature insensitivity. They were recommended for practical application in cable force monitoring.