Key Takeaways & Executive Findings
- •• Long-term tracking of CRTSⅢ slab ballastless track reveals that irregularities with wavelengths longer than 10 m show larger amplitudes, faster evolution, and linear growth, primarily impacting vehicle stability. • Shorter-wavelength irregularities (<10 m) exhibit minimal evolution and mainly affect vehicle safety, highlighting the need for wavelength-specific management. • The arching of 32 m simply-supported beam bridges induces periodic irregularities with evolution rates significantly higher than other wavelengths, requiring focused monitoring. • Recommended classified limits for track irregularity are proposed based on limit-exceeding probability of safety and stability indexes, aiding maintenance strategies for high-speed railways.
Abstract
Abstract: As one of the major high-speed railway ballastless track structures in China, CRTSⅢ slab ballastless track has been laid for more than 6500 km. However, there are no detailed studies on its track irregularity deterioration throughout extended service periods, which may threaten the safety and stability of high-speed vehicles (HSV). In this study, a long-term tracking detection of CRTSⅢ slab ballastless track irregularities has been conducted, revealing its annual evolution law. An HSV-track coupled dynamics model was established to investigate the HSV dynamic responses under annual evolution of track irregularities. Considering the potential deterioration of track irregularities to extremely bad condition, the recommended classified limits for irregularity are proposed by analyzing the limit-exceeding probability of the safety and stability indexes of HSV. The results show that: taking 10 m wavelength as a demarcation, longer-wavelength irregularities exhibit larger amplitudes, faster evolution rates and a linear increasing trend, primarily affecting the stability of HSV. Conversely, shorter-wavelength irregularities exhibit smaller amplitudes and an insignificant evolution trend, predominantly affecting the safety of HSV. Furthermore, the periodic irregularity induced by the arching of 32 m simply-supported beam bridge should be paid closer attention to, as their evolution rate significantly surpasses that of irregularities at other wavelengths.
1. Introduction
High-speed railway (HSR) plays an increasingly important role in the national economy with its fast, convenient, safe and stable transportation. CRTSⅢ slab ballastless track is one of the main ballastless track structures of HSR in China [1, 2], with a laying mileage of more than 6500 km. Track irregularities of high-speed railway (HSR) exhibit pronounced nonlinear characteristics, which significantly impact the safety and stability of high-speed vehicles (HSVs) [3]. Scholars have carried out researches on the characteristics of track irregularities of HSR ballastless track [4 −6]. In general, the track regularities of CRTS Ⅲ slab ballastless track are excellent so far, and the safety and stability of HSV operation are good.
It is worth noting that the track regularities will gradually deteriorate during long-term service rather than keep a respectively stable condition. MA et al [7] carried out the research of the track state analysis, evolution law and prediction method based on the long-term track inspection data of Wuhan-Guangzhou HSR line (CRTS Ⅰ double-block ballastless track paved). XU et al [8] regarded the deterioration of track geometric irregularities as the evolution of its power spectral density (PSD), and constructed the mathematical relationship between the dynamic responses of HSV and the evolutions of track spectra, but the theory lacks the measured track irregularity data as empirical support. In general, there is a paucity of research on the deterioration characteristics of CRTS Ⅲ slab ballastless track irregularities based on track inspection data, which hinders a comprehensive understanding of the broader context surrounding the deterioration of CRTS Ⅲ slab ballastless track irregularities.
As the track irregularity is the excitation source of vehicle-track coupled system, the annual evolution of track irregularities may lead to severe dynamic responses of HSV [9], which will affect the safety and stability of HSV driving [10, 11]. Up to now, scholars have carried out a lot of researches on the influence of HSR track irregularities on HSV dynamic responses by means of system coupled dynamic model, machine learning and on-site measurements [12 −14]. LEI et al [15] studied the parameters influencing the irregularity-response coherence relationship through dynamics simulations. KARIS et al [16] derived the PSD functions of the responses of the vehicle by analytical method and studied the causes of periodic fluctuations of response spectra. ZHAO et al [17] and XIN et al [18] carried out research on the influence of short-wave (0.5 −2 m) and long-wave (above 40 m) on the HSV dynamic responses, respectively. However, the common shortcoming of these studies is that the evolution characteristics of track irregularities are not fully considered.
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GAO Rui-kai, XIN Tao, GAO Liang, MA Shuai, LIU Xiu-bo (2025). Influence of deterioration of CRTSⅢ slab ballastless track irregularity on the safety and stability of high-speed vehicles. Journal of Central South University. https://doi.org/10.1007/s11771-025-6124-y
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Frequently Asked Questions
What is the main focus of this study?
The study investigates the deterioration of track irregularities in CRTSⅢ slab ballastless track over time and its impact on the safety and stability of high-speed vehicles, proposing classified limits for irregularity management.
How was the research conducted?
Long-term tracking detection of track irregularities was performed, and a vehicle-track coupled dynamics model was established to simulate vehicle responses under annual evolution of irregularities. Limit-exceeding probability analysis was used to propose recommended limits.
What are the key findings regarding wavelength effects?
Irregularities with wavelengths longer than 10 m show larger amplitudes and faster evolution, primarily affecting vehicle stability, while shorter wavelengths mainly affect safety. Periodic irregularities from bridge arching evolve fastest.
Why is this research important for high-speed railways?
It provides insights into track degradation patterns and offers practical limits for maintenance, ensuring the long-term safety and stability of high-speed train operations.
What are the practical applications of the proposed limits?
The recommended classified limits can be used by railway operators to prioritize maintenance interventions based on wavelength-specific deterioration, improving cost-effectiveness and safety.
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