Abstract:In order to evaluate the stability of tunnel surrounding rock scientifically and reasonably, the cloud model theory is introduced to establish the evaluation system based on the cloud model. First of all, by analyzing the influencing factors of the stability of the surrounding rock of the tunnel, a comprehensive stability evaluation index system is established. Secondly, the subjective and objective weights of the indexes are determined by the improved AHP and the improved critic, the combined weights of the indexes are determined by the game theory, the digital characteristics of the cloud are determined according to the stability grading standard, the index cloud chart is generated, and the different grades of the evaluation objects are calculated. Based on the principle of maximum membership degree, the stability grade of surrounding rock is determined. Finally, the game theory combined weighting cloud model comprehensive evaluation model is applied to the tunnel stability evaluation, and compared with the extension theory and improved entropy-attribute recognition evaluation model, the research results show that the evaluation results of the established evaluation model are accurate and reliable, practical, which has a certain guiding significance for tunnel construction, and provides a new quantifiable thinking for the tunnel surrounding rock stability evaluation.