A Practicable Algorithm for Cable Force Identification Based on the Slenderness Indicator

This paper proposes a slenderness indicator (SI)-based algorithm for identifying cable force in bridge engineering. First, the cable dynamic equation is reduced through time-space coordinate transformation in the dimensionless system, and the fractional power function relationship of the dimensionless frequency-ratio and the slenderness indicator is established through the Taylor series expansion method. On this basis, a practicable algorithm is constructed, which calculates the cable force for each order frequency, and a clear engineering application scope of the algorithm for each order mode is established. The accuracy of the SI-CFI (slenderness indicator-based cable force identification) algorithm is verified through the finite element examples. The feasibility of the SI-CFI algorithm is demonstrated based on the frequencies of the bridge cables using the radar interferometry technology. The overall average error of cables is within 0.9%. It can be seen that the proposed method excels in both error control and identification stability. The algorithm is simple, intuitive, and theoretically supported, which can cover the applicable range of slenderness indicators for engineering cables, providing engineers with a standardized and practicable cable force identification solution.