论文部分内容阅读
为降低岩体各评价指标间的冲突性和评价过程中的模糊性与不确定性对评价结果的精度和信度带来的不利影响,构建基于D-S证据理论的岩体质量综合评价模型。首先,依据岩体质量影响指标和分级标准,运用欧氏距离法衡量各指标与各质量等级之间的关联程度,进而确定岩体质量基本概率分配函数(BPA)。然后,根据指标间距离以及指标间的相似度与支持程度确定指标权重,并修正BPA。最后,对修正的证据运用D-S组合规则,得出质量等级。将该方法应用到某工程实例中,并在评价过程中与可拓法进行比较,以验证其优缺点。实例研究表明,用该方法得到的评价结果与工程实际相吻合,与可拓法相比,该方法在评价精度和定量反映指标间的一致性程度上有明显优势。
In order to reduce the conflict between evaluation indexes of rock mass and the influence of the fuzziness and uncertainty in evaluation process on the accuracy and reliability of evaluation results, a comprehensive evaluation model of rock mass quality based on D-S evidence theory is established. First of all, according to the rock mass quality index and grading standards, the Euclidean distance method is used to measure the degree of association between each index and each quality level, and then the basic probability distribution function (BPA) of rock mass quality is determined. Then, according to the distance between indicators and the similarity between the indicators and the degree of support to determine the index weight, and amend the BPA. Finally, applying the D-S combinatorial rule to the amended evidence leads to a quality grade. The method is applied to an engineering example and compared with the extension method in the evaluation process to verify its advantages and disadvantages. The case study shows that the evaluation result obtained by this method agrees well with the engineering practice. Compared with the extension method, this method has obvious advantages in evaluating the accuracy and quantitatively reflecting the consistency between the indexes.