基于漂移度的隧道围岩质量分级组合评价方法

针对现有隧道围岩质量分级方法评价结果存在非一致性问题的特点，首先引入组合评价思想，选取多种已有围岩质量分级方法作为基础分级方法，建立了融合各基础分级方法优越性的隧道围岩质量分级组合评价计算模型；其次，依据不同基础分级方法评价指标的物理意义和量纲不同的特点，建立了评价指标的标准化方法，使不同基础分级方法评价结果具有可比性，以解决组合评价计算模型的组合计算方法问题；然后，针对不同基础分级方法评价结果的合理性存在差异的特点，引入漂移度概念，建立了基础分级方法合理程度的度量方法，并在此基础上，提出基础分级方法权重分配的合理确定方法，进而建立了隧道围岩质量分级的新型组合评价方法，该方法不仅可以解决不同基础分级方法评价结果的非一致性问题，更重要的是可以充分发挥各基础分级方法的优势，避免它们的不合理性，使隧道围岩质量分级更为合理；最后，通过工程实例分析，表明了该方法的合理性与可行性。

Combination evaluation method for classification of surrounding rock quality of tunnel based on drifting degree

Considering the inconsistency among the evaluation results drawn by different classification methods for surrounding rock quality of tunnels,combination evaluation idea is introduced.A model for classification of surrounding rock quality based on combination evaluation is formulated by selecting several existing classification methods for surrounding rock quality of tunnels as the fundamental methods,which may integrate the advantages of the fundamental methods.Since the physical meanings and dimensions of the evaluation indexes drawn by the fundamental methods are different,a standardized method for evaluation indexes is developed to make the evaluation results of different fundamental methods comparable so as to solve the computational problem of the calculation model based on the combination evaluation.Taking into account the differences of rationality between the evaluation results of the fundamental methods,a method for reasonable degrees of the fundamental methods is established by introducing drifting degree,based on which the weight calculation is developed.Then the combination evaluation method for classification of surrounding rock quality of tunnels is developed to make the classification method of surrounding rock quality of tunnels more reasonable,which can not only solve the problem of inconsistency among the fundamental methods,but also give full play of the fundament methods’ advantages and avoid the un-reasonability.Finally,the proposed method is used to analyze practical projects.It is shown that the proposed method is feasible and reasonable.