Multi-level fuzzy evaluation model for karst highway tunnel safety
To analyze tunnel safety, the coupling effect of multi-factor should be taken into account. Referring to railway tunnel health evaluation model, the karst highway tunnel safety is classified into five grades. After that, the factors affecting tunnel safety are dealt with by the way of Analytic Hierarchy Process (AHP). Then, the qualitative indexes are classified into five levels according to tunnel safety. Furthermore, the membership function, which follows the Gaussian Distribution, is applied to determine quantitative evaluation indexes. Meanwhile, relied on the expert scoring method of system theory, those factors are assigned weights and the treated karst caves are set up as uncompacted backfill model, and then the three-grade fuzzy comprehensive evaluation model is built for inservice highway tunnel safety in karst area. With this model, the safety of Huilong-shan tunnel is evaluated and the safety value is judged by the maximum membership law.