The occurrence of geologic hazards often results in widespread failures of road transportation infrastructures， significantly affecting regional transportation activities. To assess the transportation system’s resilience to disasters， this study introduces a method for evaluating the robustness of road networks， considering the influence of geologic disasters. Utilizing historical disaster data， the impact of disasters on road transportation is quantified as the damage probability to network segments. The vulnerability index of road segments is defined based on the damage probability and indicators of the importance of road segments. Employing percolation theory， the study evaluates network robustness from structure and performance perspectives， simulating and comparing changes in robustness indicators under different attack strategies. Structurally， the critical percolation threshold is determined through the connectivity subgraph scale as the robustness index. Regarding performance， overall network accessibility is used to assess performance changes during the percolation process. Results show that the network is most vulnerable to attacks based on road segment vulnerability indicators， with both structural and performance assessments indicating that the primary network components constitute 40%~50% of the overall structure. Meanwhile， the study identifies potential critical road sections using the percolation threshold and the peak of robustness metric changes and proposes a method to distinguish effective critical road sections by comparing their impact on the overall network. The research framework， spanning from robustness assessment to critical section identification， offers insights for evaluating and enhancing the robustness of transportation networks， providing theoretical support for network planning and management.