Correlation Analysis of Large-Span Cable-Stayed Bridge Structural Frequencies with Environmental Factors Based on...

Area of Science:

• Structural Engineering
• Environmental Monitoring
• Civil Engineering

Background:

• Bridge dynamic characteristics are sensitive to environmental factors.
• Understanding temperature and humidity impacts is crucial for structural health assessment.

Purpose of the Study:

• To investigate the influence of environmental temperature and humidity on the modal frequencies of the Jintang Hantan Twin-Island Bridge.
• To establish a reliable method for assessing bridge structural health under varying environmental conditions.

Main Methods:

• Covariance-Driven Stochastic Subspace Identification (SSI-COV) to identify modal frequencies.
• Correlation analysis to examine frequency relationships with temperature and humidity.
• Support Vector Machine Regression (SVR) to model temperature effects on frequencies.

Main Results:

• Temperature was identified as the primary factor influencing frequency variations, showing a strong linear correlation.
• Humidity exhibited minimal correlation with frequency changes.
• The SVR model effectively predicted frequency based on temperature, with reliable fitting residuals.

Conclusions:

• Temperature significantly impacts bridge modal frequencies, while humidity has a negligible effect.
• The developed SVR model accurately captures and predicts temperature-induced frequency shifts.
• Post-analysis smoothing of frequency data, after accounting for temperature effects, revealed significantly reduced daily fluctuations, enhancing structural health assessment accuracy.