• Conducted the first comprehensive in-situ experimental investigation of vibration characteristics in high-speed railway turnouts (HSRT). • Identified spatial-frequency distribution patterns of vibrations across different rails within HSRT. • Analyzed the impact of various rail fastening methods and connection components on HSRT vibration behavior. The High-Speed Railway Turnout (HSRT) is a complex, non-periodic assembly structure with asymmetric longitudinal distribution along the track, subjected to broadband wheel-rail impact loads. These features lead to highly intricate mechanical behavior. Gaining insight into the vibration characteristics of the HSRT is essential for understanding and optimizing its structural performance and ensuring the service safety of railway infrastructure. This study, for the first time, conducted a systematic in-situ vibration test to reveal the spatial-frequency distribution patterns of vibration characteristics across different rails of the HSRT and to investigate the influence of rail fastening methods and various connection components on its dynamic behavior. The findings indicate that the vibration characteristics of each HSRT rail vary continuously along the track due to special structures, such as variable rail cross-sections and connection components, which generally amplify low-frequency responses below 120 Hz. Above 790 Hz, the RPDFRF amplitudes exhibit a “striped” distribution due to the half-wavelengths of “pinned–pinned” and similar modes approximately matching the sleeper spacing, though this pattern is less pronounced in variable cross-section regions. In these regions, the increased railhead width raises the system mass, lowering the natural frequency and causing an overall shift of the RPDFRF amplitudes toward lower frequencies. Different fastening methods mainly affect RPDFRF amplitudes and peaks below 240 Hz, while fastening constraints significantly reduce amplitudes in the 867–1820 Hz range. Various connection components predominantly influence the RPDFRF amplitude and peak distribution within 300 Hz for each rail.
Ma et al. (Sun,) studied this question.