An extended TODIM-based model for evaluating risks of excavation system

This paper presents a risk evaluation model of excavation system. The model is developed based on extended TODIM method (TODIM is an acronym in Portuguese for Interactive Multi-criteria Decision Making). Developed model consists of three phases: data collection and benchmark risk level classification, extended TODIM method application and risk status perception. Excavation system is divided into 19 sub-systems based on monitored scheme, and twelve influential factors are determined. Sub-systems of excavation in high risk status are identified via the developed model. Impacts of coefficient θ in extended TODIM method on risk status results are investigated. An excavation construction project in Tianjin is adopted. Evaluation results show that sub-systems with high-risk status can be identified, which are consistent with the engineering practices. Finally, sensitivity analysis is conducted to increase the robustness of developed model. The developed model can provide a comprehensive risk status perception of sub-systems of excavation which can mitigate and manage the risks during excavation construction.