距离判别法在公路隧道围岩分类中的应用

Application of Distance Discriminant Analysis Method in Classification of Surrounding Rock Mass in Highway Tunnel

将距离判别分析方法应用于公路隧道围岩类别判定问题中,结合前人研究经验,选用隧道洞室围岩岩石单轴饱和抗压强度σc、节理平均间距d、岩石质量指标RQD、地下水情况作为围岩类别判定的距离判别分析模型判别因子,以前人实际工程中公路隧道围岩实测数据资料作为训练样本进行分析计算,建立围岩类别判定的距离判别分析模型。采用回判估计方法对判别结果进行验证,误判率为零,将对样本数据的回判结果与前人应用神经网络方法判别结果对比,判别结果一致。运用距离判别分析模型对浙江省诸永高速公路枫树岭隧道围岩类别情况进行判别,将所选洞段围岩情况判定为Ⅳ类,与规范方法判定结果一致。

A method of distance discriminant analysis is used to classify the surrounding rock of highway tunnel. Based on experiences, several key factors, such as the uniaxial compressive strength σc, average spacing of joints d, values of rock quality RQD and groundwater condition, are selected to be parameters of discriminant analysis model. So a model of distance discriminant analysis is established though training a large set of surrounding rockmass samples which come from a series of tunnel projects. The discriminant results are validated and have a low misjudgment ratio. The results are also the same as the results from ANN method. Furthermore, the analysis result of the class Ⅳ for surrounding rock in selected parts of Fengshuling tunnel of Zhuyong highway in Zhejiang Province, which is calculated by the method of distance discriminant analysis, is in good agreement with standard method.