Disease Evaluation of Existing Tunnel Lining Based on AHP-Extenics

The existing tunnel lining structure is easily affected by geological conditions, disturbance in the early stage of construction and operation in the later stage. This paper analyzes the main factors affecting the lining structure diseases of existing tunnels from three aspects of engineering construction, natural environment and engineering geology, starting from 13 independent factors affecting the lining structure diseases of existing tunnels. First of all, the index system of the formation factors of lining diseases in the reconstruction and expansion tunnel is established by using the analytic hierarchy process (AHP), and the hierarchical index system is put forward. Based on AHP-Extenics model, the evaluation method of lining structure disease of existing tunnel is proposed. Then, combined with engineering practice and expert scoring, the weight of safety evaluation index is determined, and the safety evaluation index and weight are expanded by using correlation function. Finally, the disease evaluation grade of the existing tunnel lining structure is obtained. This method uses the formal Extenics comprehensive evaluation model, which makes the calculation results more objective and provides a new method for the disease evaluation of the existing tunnel lining structure.