Tension estimation for cross-linked cables based on vibration frequencies with a dynamic stiffness approach

Using vibration measurements to determine tension forces is a well-established technique for diagnosing tensioned slender members. Traditional approaches are unsuitable for cables attached to transverse fasteners or intersect clamps. Therefore, the assessment process for linked cables generally requires unlocking and reconnecting the fasteners and clamps during vibration tests. This paper introduces an integrated idea of using single vibration measurements with simple analytical models to develop a practical scheme to estimate the tension of individual members for cross-linked cables. The development of the method relies on using simple dynamic stiffness formulas of the string model such that iterative approximations or optimised searching with numerical coding can be effectively executed for both the backward estimation and forward verification stages of the assessment procedure. The effectiveness of the proposed methodology has been numerically studied and verified with selected data from field tests. The procedure can provide a better on-site tool for the vibration tests of fastener-restrained suspenders and cross-linked cables.