Evaluation of rock stability based on combined weighting-unascertained measurement theory

Owing to multi-objectivity and uncertainty in the evaluation of rock stability, the modified analytic hierarchy process (AHP) and the entropy method are used to calculate the weights of factors. On this basis, a new combination rule is proposed to determine the weight which can help us to get a relatively objective and accurate result. According to the influence factors and grading standards of the rock stability, six qualitative indices and eight quantitative indices are selected. Based on the combined weighting-unascertained measurement theory coupled valuation model, the stabilities of 12 surrounding rocks in the study area are assessed and analyzed by using the unascertained measurement function, combination weighting and confidence criterion. The stability of each surrounding rock is obtained. Compared with the results of field evaluation and fuzzy matter-element, the evaluated results are consistent with the actual situations. Therefore, the combination weighting- unascertained measurement theory evaluation model is scientifically reasonable for the rock stability. The integrality of assessment object information is ensured, and the accuracy, objectivity and reliability of the evaluated results are guaranteed. The proposed model can be applied to the actual projects.