Abstract Equivalent continuum models estimating the deformability of complexly fractured rock masses may incur significant discrepancies. This paper proposes an equivalent discrete fracture network (E-DFN) method to proficiently capture the non-continuous characteristics of rock masses while significantly reducing computational cost compared with traditional discrete fracture network (DFN) models. A significance index of individual fractures is defined to quantitatively evaluate their impact on the elastic modulus. Accumulative significance indices are then generated to define E-DFNs containing representative quantities of fractures. Numerical simulations are conducted with E-DFN models using UDEC (universal distinct element code). The relationship between elastic moduli of complexly fractured rocks and models with E-DFNs is established by an extrapolation function obtained through regression analyses based on an assumption of the marginal diminishing effect of modulus reduction. The proposed method is validated by stochastic DFNs with different geometric configurations. The results show that reasonable estimation with small errors is achieved by the extrapolation of density-reduced E-DFN models. The E-DFN method strikes a balance between result reliability and computational intensity.

中文翻译：

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复杂裂隙岩体变形能力数值估计的等效离散裂缝网络方法

摘要 估计复杂裂隙岩体变形能力的等效连续介质模型可能会产生显着差异。本文提出了一种等效离散裂缝网络（E-DFN）方法，以熟练地捕捉岩体的非连续特征，同时与传统的离散裂缝网络（DFN）模型相比，显着降低了计算成本。定义单个裂缝的显着性指数以定量评估它们对弹性模量的影响。然后生成累积显着性指数以定义包含代表性裂缝数量的 E-DFN。使用 UDEC（通用不同元素代码）对 E-DFN 模型进行数值模拟。复杂裂缝岩石的弹性模量与具有 E-DFN 的模型之间的关系是通过基于模量减少的边际递减效应的假设通过回归分析获得的外推函数建立的。所提出的方法通过具有不同几何配置的随机 DFN 进行验证。结果表明，通过密度降低的E-DFN模型外推实现了具有较小误差的合理估计。E-DFN 方法在结果可靠性和计算强度之间取得了平衡。结果表明，通过密度降低的E-DFN模型外推实现了具有较小误差的合理估计。E-DFN 方法在结果可靠性和计算强度之间取得了平衡。结果表明，通过密度降低的E-DFN模型外推实现了具有较小误差的合理估计。E-DFN 方法在结果可靠性和计算强度之间取得了平衡。