Abstract: In order to solve the deficiency of fuzziness and complexity in the stability evaluation of the construction site above the old goaf,based on the triangular fuzzy analytic hierarchy process and cloud model,the stability evaluation of the construction site in the goaf section of Mianluan Expressway is studied.First of all,taking into account the hydrogeological conditions,mining technical conditions,site deformation characteristics and external disturbance,a comprehensive evaluation model of construction site stability above the old goaf is established.Secondly,considering the complexity and uncertainty of the evaluation process,the analytic hierarchy process of triangular fuzzy function is proposed to determine the weight of each evaluation index.Finally,the evaluation set of the influencing factors in the study area is transformed into the digital characteristics of the cloud model by using the cloud model,and the stability grade of the study area can be obtained by combining the weight of the evaluation index.The study results are applied to the stability evaluation of the construction site of Mianluan Expressway.The results show that the stability of construction site is mainly stable and basically stable,and based on this,the countermeasures of subgrade and pavement treatment that are applicable to the goaf section of Mianluan Expressway are proposed.

Key words: goaf,triangular fuzzy analytic hierarchy process,cloud model,stability evaluatio