Analyzing Coupled Risk Mechanisms and Key Factors in Coal Mine Fires: An N-K Model and Complex Network Approach

Coal mine fires represent one of the major threats constraining sustainable and safe production in the coal industry. To investigate the mechanisms of accident causation and coupling evolution, this study proposed a fire risk analysis method integrating the N-K model (a model for quantifying interactions among system components) with complex network theory. Seventy-five coal mine fire accident cases were selected as samples to identify the coupling types and coupling mechanisms among human, management, technology, environment, and equipment risk factors. The N-K model was employed to determine accident coupling types and calculate risk coupling values. Based on association rule mining among risk factors, a coal mine fire risk network model was constructed. By integrating accessibility characteristics derived from complex network analysis with the N-K model, the normalized out-degree of network nodes was adjusted using N-K coupling values to better reflect node influence, thereby identifying key risk factors. The results showed that management factors were the dominant dimension driving risk coupling, and an increase in the number of coupled factors significantly affected the level of coal mine fire risk. The top four key risk factors were inadequate safety supervision by regulatory authorities, insufficient safety training and education, illegal production organization, and incomplete safety technical measures. Finally, targeted prevention and control strategies were proposed. The findings provide critical support for advancing sustainable and safe coal mine production by informing targeted safety interventions and optimizing resource allocation in safety management.