Concrete surface deterioration detection and classification using YOLO26n: an AI-driven approach

An efficient and reliable system for the classification and detection of concrete surface deterioration is essential for timely maintenance and extending the service life of concrete structures. Conventional manual inspection methods are labor-intensive, time consuming, and prone to human error, which can lead to delayed remediation and increased repair costs. This study presents an artificial intelligence–based approach using the You Only Look Once 26 Nano (YOLO26n) model to automatically detect and classify various types of concrete surface degradation, including exposed reinforcement, rust stains, scaling, spalling, cracks, and efflorescence. A dataset comprising 6,806 images, collected and manually annotated from publicly available sources, was partitioned into training, validation, and test sets using an 80%, 10%, 10% split. To enhance model robustness and generalization, multiple data augmentation techniques such as scaling, translation, and color jittering were applied. The proposed model was implemented using the Ultralytics YOLO framework, and its performance was evaluated using precision, recall, F1 score, and mean Average Precision (mAP). Experimental results demonstrate that the YOLO26n model achieves a precision of 95.8%, recall of 97.7%, F1-score of 0.967, mAP@50 of 98.9%, and mAP@50–95 of 85.5%. These results indicate strong detection accuracy and localization performance, outperforming traditional manual inspection methods as well as existing deep learning models such as YOLOv5n, YOLOv8n, YOLO11n, and YOLO12n. The proposed automated system significantly reduces inspection time, improves detection consistency, and enables efficient and cost-effective infrastructure maintenance.