Causes of structural defects to bus rapid transit (BRT) facilities: Example of Xiamen BRT system

Based on the health diagnosis data of structural defects in reinforced concrete components of Xiamen Bus Rapid Transit (BRT) system, this paper presents a principal component analysis (PCA) - based method to detect the causes of structural crack defects of BRT. The defect data are collected from the health diagnosis work on facilities of Xiamen BRT system, and is divided into six categories: a) aged structure, b) structural weight, c) weather-caused, d) external force, e) BRT operation and f) facility-use. The six dimensions of causes are mapped into the PCA model to calculate the contribution degrees - according to which, the causes of structural defects of BRT facilities are categorized and evaluated. Finally, the main reasons for the structural defects of the BRT system are weighted and discussed.