Comparison of the Track Geometry Indices of Various Countries: A Case Study of Beijing-Guangzhou Railway

Effective maintenance of railway track geometry is crucial for ensuring better ride quality and operational performance of the track, prompting substantial investments by railway authorities. Track geometry indexes (TGIs) are an essential statistical measure that are used to assess the track quality based on various geometric parameters. This study provides a detailed comparison between TGIs of different countries, that is, the Chinese track quality index (CTQI), the Indian track geometry index (ITGI), Poland (J-coefficient), and Sweden (Q-index). The track geometry data from the Guangzhou-Beijing track line in China was collected using a track inspection vehicle. This study investigates the relationships between geometric parameters and TGIs using Pearson correlation analysis and artificial neural network (ANN). The research findings showed that ITGI identified the need for basic maintenance in specific sections of railway tracks, while the TGIs of other countries showed such sections in good condition, showcasing the significant efficacy of ITGI. The correlation coefficient and ANN model highlighted a less pronounced relationship between gauge and TGIs. Also, the sensitivity analysis by the ANN method, showed the influence of vertical and horizontal geometric parameters on TGIs of all four countries, with effect size values of 97.7%, 97.0%, 72.8%, and 72.8% for ITGI, Sweden Q-index, Poland J-coefficient, and CTQI, respectively. The results showed that vertical and horizontal geometric parameters are the most significant factors influencing the overall TGI values. ITGI provides better results by assigning more weight to the track’s alignment (horizontal parameter). These results provide valuable guidance to railway managers to enhance track performance and quality by scheduling efficient maintenance.