Influence of strings on the propagation of bending energy in beams

Structural dynamics does not account for the process of energy transmission within a structure, which limits its application to super-large bridge structures. Unlike previous studies, this research employs energy distribution analysis. A combined beam-string structure, simulating a cable-stayed or suspension bridge, is used to analyze the law of energy transfer. Displacement consistency and internal force continuity are applied to establish the governing equations, which are then solved using the incident wave method. Finite element simulations are conducted to validate the theoretical predictions of energy distribution ratios. The results indicate that as the incident wave frequency increases, the proportion of energy transmitted into the string decreases, thereby reducing its energy diversion effectiveness. This study reveals that the string plays a highly effective auxiliary role in resisting low-frequency energy generated in the main beam by forces such as wind and earthquakes. Furthermore, a larger inclination angle between the string and the main beam significantly enhances the energy diversion capability of the string.