Analysis of the Dynamic Characteristics of Taxiway Bridges During Different Phases of Aircraft Taxiing

Airport taxiway bridges characterized by large span-to-width ratios exhibit significant spatial mechanical behavior. Given the substantial magnitude of aircraft loads and the comparable scale of landing gear wheelbase to bridge span length, the mechanism by which aircraft influence the dynamic characteristics of taxiway bridges during different stages of taxiing remains inadequately understood. This investigation initially evaluates the effects of additional mass loads and spring-mass loads applied at various locations on the dynamic performance of the taxiway bridge. Subsequently, a coupled aircraft-bridge vibration analysis framework was utilized to examine the bridge's dynamic response throughout each stage of aircraft traversal. Results indicate that the influence of the added mass model on the frequencies of each mode of the taxiway bridge is positively correlated with the amplitude of that mode at that location. The closer the added mass position is to the node line of that mode, the smaller its impact on that frequency. In the aircraft-bridge coupled vibration analysis, the staged dynamic response of the taxiway bridge provides better identification of bridge modal information compared to using the full-process dynamic response of the bridge during aircraft passage. Aircraft loads crossing the bridge at off-center positions can excite and measure more bridge modal information. When the nose landing gear is on the bridge, the higher-order bridge modes obtained based on the bridge response are relatively more accurate. When the main landing gear is on the bridge, the lower-order bridge modes obtained are clearer and more accurate. When both the nose and main landing gears are on the bridge, relatively richer modal information can be obtained.