Health-monitoring methods for long-span cable-stayed bridges

Abstract

It is important to consider the impact of non-uniform excitations on long structures, including bridges. This study investigates how the dynamic behaviour of a cable-stayed bridge is impacted by multiple sources of support excitation. The bridge is simulated by using the Abaqus software. The results indicate that various parameters, including cable stresses, tower and support base shear, and the influence of multiple sources of support excitation on a bridge, lead to significant changes in displacements. For instance, in non-uniform excitation mode, the two end supports display an average enhancement of approximately 25% in comparison with the uniform excitation mode; for the towers, the average increase is 23%. Moreover, an examination is conducted into the effectiveness of various health-monitoring techniques, such as mode-shape curvature and energy index (EI), to find the damages on the bridge, as bridges are important infrastructures and monitoring them during their operation could save lives and costs. In this regard, the Matlab software is used and the stiffnesses of some parts of the deck are decreased as intentional damages. After comparing the methods mentioned, the research indicates that using the EI based on strain responses is a highly effective means of detecting damage.