Deformation and disease detection of Tulou based on multi-source 3D point cloud fusion

This study applies high-precision industrial metrology to the conservation of rammed-earth buildings (Tulou), establishing a structural health monitoring (SHM) framework based on 3D laser scanning and UAVs. By fitting “ideal” geometric reference surfaces through reverse engineering and incorporating efficient point cloud subsampling algorithms to significantly enhance processing efficiency, we utilized graphical data to develop specific deformation detection methods for irregular walls. This enabled the precise quantitative assessment of roundness, verticality, flatness, and column inclination. This approach effectively bridges the gap between advanced point cloud processing and traditional architectural pathology, successfully transforming assessments from subjective manual inspections to industrial-grade, objective geometric diagnoses. These findings not only enhance the scientific accuracy of World Heritage conservation but also provide a reproducible digital technical solution for the preservation of rammed-earth heritage globally.