Train-Induced Vibration Monitoring of Track Slab under Long-Term Temperature Load Using Fiber-Optic Accelerometers

Area of Science:

• Civil Engineering
• Structural Health Monitoring
• Geophysics

Background:

• Real-time monitoring of high-speed railway track slab deformation is crucial for operational safety.
• Existing methods may lack the precision or long-term capability required for continuous assessment.
• Train-induced vibrations offer a potential data source for structural health monitoring.

Purpose of the Study:

• To develop and validate a novel, long-term, real-time monitoring method for track slab deformation.
• To investigate the relationship between train-induced vibrations, wavelet packet energy (WPE), and track slab deformation.
• To assess the influence of temperature loads on track slab deformation and its correlation with vibration responses.

Main Methods:

• Utilized fiber optic accelerometers to record train-induced vibrations over an extended period.
• Applied wavelet packet energy (WPE) analysis to the frequency bands corresponding to train-induced vibrations.
• Conducted a year-long field test on the Beijing-Shanghai high-speed railway.

Main Results:

• Established a vibration response law linking track slab deformation to the WPE of specific frequency bands.
• Observed maximum WPE characteristic index values in winter and summer, correlating positively with temperature differences.
• Demonstrated consistency between WPE-based findings and track slab deformation patterns under daily and long-term temperature loads.

Conclusions:

• The proposed method using fiber optic accelerometers and WPE enables effective long-term, real-time monitoring of track slab deformation.
• This approach provides a new tool for understanding and managing the structural health of high-speed railways.
• The findings highlight the significant impact of temperature variations on track slab behavior and its detectability through vibration analysis.