2026 年 91 巻 843 号 p. 660-671
This study presents an integrated method that combines deep-learning models and image-processing algorithms to detect cracks in RC member damage images while distinguishing crossings, discontinuities, and branches. Cracks are parameterized by a luminance-based polyline approximation; widths at approximation nodes are classified by a trained model, and lengths are measured from nodes. Damage images from full-scale RC partial-wall lateral-loading tests served for training and evaluation. The image-based lengths achieved an average ratio of 0.99 relative to manual measurements, and width classification accuracy was 0.88. Findings indicate crack segments with quantitative length and width attributes can be extracted.