FREQUENCY CALCULATION OF CABLES CONSIDERING BENDIING STIFFNESS MODIFIED BY CABLE TENSILE FORCES

The natural frequency of cables is largely influenced by their bending stiffness. The present researches on this topic all consider the bending stiffness as a constant parameter under any circumstances. However, recent experimental and theoretical studies have shown that cable bending stiffness is related to its tensile forces. Thus, cable bending stiffness should be modified by its tensile forces when utilized to calculate the natural frequencies. A nonlinear model for the determination of bending stiffness is thusly proposed. The analytical expression for the calculating of cable natural frequency is derived. The numerical analysis demonstrates that the modified bending stiffness is significant for obtaining a more precise frequency of cables, especially for relative short cables.