Research on bridge spatial deformation monitoring using light poles and displacement-relay theory

• Novel approach for bridge deformation monitoring using light poles and displacement-relay technology. • Practical sensor system designed for long-span structures, ensuring real-world applicability. • Advanced methods like sub-pixel recognition and wavelet denoising enhance measurement accuracy. • High-precision real-time monitoring scheme for continuous assessment of structural integrity. The growing traffic on municipal bridges demands effective methods for monitoring spatial deformations to ensure structural safety. Traditional measurement techniques often fall short in terms of efficiency and precision. This study presents an innovative bridge deformation measurement system that employs light poles and displacement-relay theory, integrated with high-resolution optical cameras, sub-pixel image recognition algorithms, and IMU data. Laboratory experiments involved chain camera units and multiple data processing methods, including sub-pixel recognition and wavelet denoising. Results showed that sub-pixel recognition with four-layer wavelet denoising achieved the highest accuracy, aligning closely matching the performance of commercial equipment. Field tests on the Xinwuyi and Dinghuaimen Bridges under varying traffic conditions confirmed the system’s reliability. The study concludes that the system effectively captures dynamic load variations, enhancing the accuracy of spatial deformation measurements. Future work will refine error analysis and data processing methods to further enhance the system’s practical applicability.