Comprehensive assessment of geological hazard safety along railway engineering using a novel method: a case study of the Sichuan-Tibet railway, China

The Sichuan-Tibet Railway (STR) in China is of profound significance for Tibet's long-term development. Construction of railway reshapes the landscape it passes through and consequently influences the geological hazard risk. Despite the importance of railway construction, there remains a paucity of previous studies involving this factor. In this paper, we make a straightforward development on our previous study that a novel index system, notably considering the effect of railway construction is proposed for geological hazard assessment. Different from regional assessment, the concept of the line element is introduced, and the geological hazard risk along STR is comprehensively evaluated using matter-element extension model (MEEM), gray correlation model (GCM), and support vector machine (SVM). Receiver operating characteristic curve (ROC) analysis demonstrates that SVM performs better among the models. Results further indicate that a reduced performance of SVM in the ROC test appears to accompany with the absence of the construction factor. This finding highlights the essential role of construction in geological hazard assessment for the railway.