岩体块度指数及其工程意义

Rock-mass block index and its engineering practice significance

根据《水利水电工程地质勘察规范》中对岩体结构的分类标准 ,提出了岩体块度指数的概念 ,将实测岩芯长度按 3～ 10cm、 10～ 30cm、 30～ 5 0cm、 5 0～ 10 0cm和大于 10 0cm等 5级岩芯长度 ,获得率进行加权平均 ,综合表征岩体块度特征及结构类型 .通过大量实测资料证明岩体块度指数在一定程度上能反映岩体的完整性与相应力学性质的变化特点 .比岩石质量指标更能准确地反映岩体块度及其结构特征 ,其工程意义更为显著 .

Rock\|mass block index ( RBI ) for indicating the properties of rock is proposed. The index is defined as the sum of weighted drill\|core recovery ratio for differnet lengths. Based on the current code for classification of rock\|mass structure in China, 5 grades of length are suggested, namely 3-10cm,10-30cm,30-50cm,50-100cm and >100cm. The correlation analyses of relationship between RBI and rock quality designation, RBI and coefficient of rock\|mass sound\|degree, RBI and deformation modulus of rock\|mass show that the RBI can synthetically reflect the rock\|mass block properties and its structure.