Joint Identification of Cable Force and Bending Stiffness Using Vehicle-Induced Cable–Beam Vibration Responses

Abstract

Cables play an important role in the structure of cable-stayed bridges. The cable force is an important indicator for the construction control, health monitoring, and performance evaluation of cable-stayed bridges. In practice, the boundary conditions of the cable are complex and changeable, and most of the existing formulas for cable force identification are derived from the assumption of some ideal boundary conditions. The boundaries of the cable are disturbed due to vehicle-induced beam vibration during the operation of bridges. The purpose of this study is to establish the cable–beam transmissibility function (CBTF) from the vehicle-induced vibration response of the main beam and cable and propose a new joint identification method for cable force and bending stiffness considering boundary disturbances. First, a theoretical model of the cable considering boundary disturbances is established. Then, the response transfer relationship between the anchorage of the beam end of the cable and a point on the cable is derived, as is the CBTF. Next, a parametric study is carried out to verify that the CBTF can characterize the inherent properties of cables under boundary disturbances. Then, the joint identification algorithm for determining cable force and bending stiffness is proposed. Finally, the feasibility of the proposed CBTF for identifying cable force and bending stiffness is verified by numerical simulations of a single cable and a cable-stayed bridge. The proposed method is suitable for studying the excitation of random vehicles during bridge operations, which is very significant for the safe service and timely maintenance of bridge cables.