Integrated UAV-Based Surface Curvature Analysis and Intelligent Compaction Monitoring for Nondestructive Evaluation of Road Embankment Quality

Nondestructive testing (NDT) techniques are increasingly required in earthwork construction to overcome the spatial limitations of conventional point-based quality control methods. In road embankment construction, surface flatness and compaction homogeneity strongly influence structural performance and long-term durability. This study presents a nondestructive and noncontact evaluation framework integrating UAV-based photogrammetry with intelligent compaction monitoring. High-resolution UAV imagery was used to generate digital elevation models (DEMs), from which surface roughness was extracted using fast Fourier transform (FFT) filtering. Terrain curvature indices were applied to characterize local surface irregularities, while continuous compaction control (CCC) data were collected using an intelligent vibratory roller equipped with GNSS and acceleration sensors, providing compaction meter value (CMV) distributions over the entire embankment. Field experiments demonstrated that curvature anomalies identified from UAV data corresponded well with zones of low CMV, and strong correlations with conventional quality tests confirmed that the proposed framework enables full-area nondestr