Recursive optimization method for monitoring of tension loss in cables of cable-stayed bridges

A simple method is introduced for the detection of damage in the cables of cable-stayed bridges. The approach presented herein utilizes the change in support reactions to localize and quantify the damage in the cables. Determination of support reactions was achieved by detection of the deck element shear forces adjacent to the supports. The analytical approach is formulated as a recursive optimization damage detection technique, in which model updating is employed to account for the changes in the cable stiffness as a result of damage. The efficiency of this approach was evaluated on a reduced-scale cable-stayed bridge in the laboratory. In addition to the laboratory experiments, the proposed approach was also evaluated by simulating damage in an actual cable-stayed bridge through numerical studies. Several different damage scenarios with various levels of damage were considered in the experiments, as well as in the numerical simulations. The results indicate that the proposed method is capable of identifying the location of the damaged cables in the bridge for cases involving up to two damaged cables.