Health monitoring methods on long-span cable-stayed bridges

It is important to consider the impact of nonuniform excitations on long structures including bridges. This study investigates how the dynamic behavior of a cable-stayed bridge is impacted by multiple sources of support excitation. The bridge is simulated by applying the ABAQUS software. The results show that different parameters such as stresses in cables, base shear of towers and supports, and when multiple sources of support excitation affect a bridge, the displacements undergo significant changes. For instance, in nonuniform excitation mode, the two end supports display an average enhancement of approximately 25%, in contrast, the towers exhibit an average increase of 23% in comparison with the uniform excitation mode. Moreover, an examination is conducted into the effectiveness of various health-monitoring techniques, such as mode-shape curvature (MSC) 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, 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 indicated that using the EI rest on strain responses is a highly effective means of detecting damage.