Vibration-Based Monitoring for Transverse Cooperative Working Performance of Assembled Concrete Multi-Girder Bridge: System Design, Implementation and Preliminary Application

The hinge joints of the assembled concrete multi-girder bridge (ACMGB) are the main components of transverse transmission of loads and the decline of their transmission capacity would lead to the degradation of the transverse cooperative working performance (TCWP) of the multi-beam system. As the key working performance of this kind of bridges, its severe degradation would result in the single-girder-bearing phenomenon inducing bridge collapse. In order to detect TCWP degradation timely, this paper proposes a vibration-based monitoring scheme of the ACMGB, where structural vibration information are collected by accelerometers and dynamic strain guages at the bottom of girders in mid-span. These monitoring data are then used for identifying transverse mode shape of the multi-beam system and its derivated index in order to evaluate TCWP. This scheme has been implemented on three adjacent ACMGBs in Tongji Road Viaduct and the preliminary analysis of monitoring data proves the effectiveness and rationality of the monitoring scheme proposed in this paper, which has the potential of the TCWP evaluation.