ABSTRACT
The number of independent variables is the primary problem in accurately identifying bridge cable and pole parameters, which is analyzed from three aspects: transcendental equation form, finite element form, and dynamic stiffness form. According to the π theorem of the dimensional analysis, there are two independent variables in the frequency characteristic equation. For the uniform equal-length cables described discretely by finite elements, the vibration frequency matrix has the characteristics of band sparseness, symmetry, positive definiteness, and periodicity, and the LU triangular decomposition technique is used to prove the existence of two independent variables inductively. On this basis, it is shown that there are also two independent variables in the form of the dynamic stiffness frequency characteristic equation. Finally, the numerical example verifies that there are two independent variables in the finite element discrete model independent of the cell's discrete form.
