隧道围岩分级的距离判别分析模型及应用

Study and Application on Distance Discriminant Analysis Model in Tunnel Surrounding Rock Classification

隧道围岩的分级是隧道工程中的一项重要研究工作。将距离判别分析方法应用于隧道围岩分级问题中,建立隧道围岩分级的距离判别分析模型,选用岩石等级、风化程度、岩体弹性纵波波速、岩体结构、地质构造影响程度、节理裂隙发育程度和地下水情况7项指标作为距离判别分析模型的判别因子,以工程岩体实测数据作为学习样本进行训练,建立相应判别函数对待判样本进行分级,并利用回代估计方法进行检验。并将建立的模型运用到实际隧道工程的围岩分级判别中。研究结果表明距离判别分析模型分级性能良好,预测精度高,回代估计的误判率很低,是隧道围岩分级的一种有效方法,可以在实际工程中进行推广。

Classification of tunnel surrounding rock is an essential research subject in tunnel engineering. Based on the principles of distance discriminating analysis （DDA）, the distance discriminating analysis model for tunnel surrounding rock classification is established in this paper. Seven indexes,i, e. , the rock grade, rock weathering degree, rock mass structure, elasticity longitudinal-wave velocity of rock mass, influence degree of geological structure, developing of joint fissure and groundwater regime, are used as the discriminating factors. Learning samples are trained with the measured data of rock mass. Corresponding discriminating functions are obtained to classify the samples to be discriminated. The re-substitution method is introduced to verify the DDA model . The model has been applied in engineering practices. It has been proved that the proposed model has good classifying performance, high prediced accuracy and low misdiscrimination rate and can be used on a wide scale in practical engineering.