Study on the dynamic characteristics of the suspender with additional dampers and a frequency-based multiple parameter identification method for the system

The measurement of tensile forces inside suspenders plays an important role in safety inspection and monitoring during construction and operation of large structural engineering projects, including arch bridges and suspension bridges. The frequency-based method is one of the most widely used methods for tension force measurement of such structure components, but it is affected by many factors, such as the additional damping from a damper and various boundary conditions. In this study, the equation of damped motion for a suspender-damper system is derived, a numerical solution method based on the finite difference scheme is given, and a frequency-based multiple parameter identification method is proposed based on the derivative of the system eigenvalue. The study shows that the position and damping coefficient of the damper exert an important effect on the frequency and the plural mode of the suspender-damper system. The influence mechanism is discussed in the study. The numerical examples indicate that the proposed parameter identification algorithm can identify multiple system parameters of the suspender with a high precision and the maximum error is no more than 1%. The influence of the errors in the frequencies is also discussed in this study.