节理网络分形在隧道超前地质预报中的应用

Application of fractal description of rock mass joint and cracks network to advanced geological forecast of tunnels

分形几何是20世纪70年代以来发展起来的研究非线性现象的理论和方法,这一理论的诞生为揭示隐藏于混乱复杂现象的精细结构和定量地描述它们提供了理论基础。将分形的方法引入到隧道的超前地质预报,通过岩体结构面网络的分维值来预测岩体的质量。结合工程实例可以看出,岩体结构具有良好的分形特征,其分形描述可作为评价结构岩体质量的标准之一。分形方法是评价岩体性质的一个有效的方法,具有广泛的应用前景。

The fractal geometry is the theory used in the field of studies of the nonlinear phenomenon which has been developed since 1970s. Based on the theory, the fine structures hidden in the chaotic and complicated phenomenon have been described quantitatively. The method of fractal has been taken into the research on the advance geological forecast of tunnels ;and the rock mass quality has also been predicted by the fractional dimension of the net of the rock mass structural plane. Combining the theory with the practical constructions, some conclusions have been drawn： the fractal characteristics of the rock mass structure are obvious; and the fractal descriptions can be used as the criterion to evaluate the rock mass quality. Therefore, the fractal method is an effective method for evaluating the properties of rock masses; and it has the extensive using prospect.