LAUSR

To obtain the design basis for the dynamic characteristic parameters of bridges commonly used in superconducting electromagnetic suspension transportation, a refined magnetic force calculation model is established to analyze the dynamic load characteristics of null-flux coils. The dynamic response laws of simply supported beams under four types of equivalent train loads are compared, demonstrating that concentrated superconducting coil load sequences provide sufficient accuracy for bridge dynamic factor analysis. Furthermore, parametric analyses are conducted to investigate the effects of vehicle spacing, bridge spans, and train formations on bridge dynamic factors, and the preferred range of common bridge spans and strategies for regulating dynamic factors are discussed. The results show that the optimal range for common bridge spans is 1.5 to 1.75 times the vehicle spacing. When the ratio of bridge span to vehicle distance is 1.5, first-order resonance of the bridge is suppressed, and the dynamic factors of first-order superharmonic resonance increase with the number of train formations. When the ratio is 1.75, it is necessary to increase the vertical fundamental frequency of the bridge to avoid first-order resonance within the range of train operating speeds. Matching a 24.3 m vehicle spacing with a 37.8 m span bridge, under a 14-car formation, both the first-order resonance and superharmonic resonance dynamic factors of the bridge are less than 1.8. This configuration represents the optimal design scheme for high-speed superconducting electrodynamic suspension systems in terms of vehicle spacing and standardized bridge spans.