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Displacement Estimation Error in Laser Scanning Monitoring of Retaining Structures Considering Roughness
Hyungjoon Seo1, Yang Zhao2, Cheng Chen2
1Department of Civil Engineering and Industrial Design, University of Liverpool, Liverpool L69 3BX, UK.
Sensors (Basel, Switzerland)
|November 13, 2021
Summary
This study analyzes point cloud data from retaining structures to assess displacement calculation accuracy. The M3C2 method demonstrated the lowest error, offering optimized parameters for precise displacement analysis in civil engineering applications.
Area of Science:
- Geotechnical Engineering
- Laser Scanning Technology
- 3D Point Cloud Analysis
Background:
- Retaining structures like concrete panels, soil-nail walls (SMW), and sheet piles are critical in civil engineering.
- Accurate displacement monitoring is essential for structural integrity and safety.
- Laser scanning provides detailed 3D point cloud data for surface analysis.
Purpose of the Study:
- To evaluate the accuracy of different point cloud processing methods for displacement calculation.
- To analyze the impact of surface conditions (roughness, curvature) on displacement errors.
- To present optimized parameters for the M3C2 method for improved displacement analysis.
Main Methods:
- Acquisition of point clouds via laser scanning of concrete panels, SMW, and sheet piles.
- Analysis of local roughness and global curvature using varying kernel sizes.
- Generation of artificial displacements (100% to 20%) for point cloud datasets.
- Calculation of displacement and errors using C2C, C2M, and M3C2 algorithms.
Main Results:
- The C2C method's accuracy is sensitive to point cloud resolution.
- The C2M method tends to underestimate displacements due to point location biases in curved areas.
- The M3C2 method exhibited the lowest displacement analysis errors across different datasets.
Conclusions:
- The M3C2 method is the most reliable for displacement analysis of retaining structures using point cloud data.
- Optimized M3C2 parameters significantly enhance the accuracy of displacement calculations.
- This research provides a foundation for improved structural health monitoring in geotechnical applications.
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