A comparative study of the tension estimation methods for cable supported bridges

Abstract

This paper presents a comparative field study of the available vibration-based tension estimation techniques for cable supported bridges. The various techniques have been applied to the four inclined stay-cables on the Seohae Grand Bridge and the seven double hangers on the Yeongjong Grand Bridge. The estimated tensions have been compared with those of static tests. For stay cables on cable-stayed bridges, it is seen that the accuracy of the estimation results is affected by the sag-to-span ratio and the bending stiffness of cables. For the hangers on suspension bridges, the clamp location ratio and the effective length are the critical factors that affect the accuracy of the estimation results. Among the various techniques, the frequency-based system identification technique shows a consistent estimation error bound of 3% for a wide range of applications.