Risk assessment of water inrush accident during tunnel construction based on FAHP-I-TOPSIS

This study introduces an innovative risk assessment method, namely FAHP-I-TOPSIS, for evaluating water inrush risks during tunnel construction. Its primary objective is to address the challenges posed by various fuzzy and uncertain factors in risk assessment, aiming to enhance the reliability of on-site risk evaluation. The method combines the Fuzzy Analytic Hierarchy Process for weight calculation and the Ideal Solution Similarity Ranking Preference Interval Technique for risk interval computation. Firstly, a comprehensive risk assessment framework is established, categorizing factors influencing tunnel water inrush into geological factors (N_i), construction technology and management (M_i), and the inherent vulnerability of the tunnel itself (V_i). These three indicator layers are further subdivided based on corresponding risk factors. The method is applied to the risk analysis of water inrush in the Shijingshan Tunnel in Zhuhai, analysing the risk weights of 16 influencing factors. It is observed that cracks and fault zones have the most significant impact on the occurrence of the incident. Through a comparison with traditional TOPSIS and VIKOR methods, which calculate a single risk value, the study demonstrates that FAHP-I-TOPSIS effectively integrates various fuzzy and uncertain factors, providing a reasonable level of risk assessment. It enhances adaptability to on-site errors, significantly improving the robustness of water inrush risk assessment during tunnel construction and sustainable management.