Faulted Rock Slope Stability Under Blasting Excavation Using Copula‐Based Rotated Anisotropic Random Fields

Abstract

ABSTRACT Blasting excavation can induce permanent displacement in faulted rock slopes and adversely affect slope stability. Most existing stability assessments use deterministic approaches and therefore do not adequately account for the spatial variability and cross‐correlation of geomechanical properties. In addition, conventional assumptions of transverse anisotropy and the arbitrary selection of copula models may bias blast‐design assessments. This study develops a stochastic framework that integrates rotated anisotropic random fields with copula models to characterize spatially variable rock properties. The effects of copula selection and rotated anisotropy on the statistical distributions of permanent displacement and a displacement‐based risk index are investigated. The framework is demonstrated through an engineering case study and compared with conventional deterministic analysis. The results indicate that the commonly used Gaussian copula tends to overestimate slope stability, whereas strata orientation, scale of fluctuation, and the correlation between cohesion and friction angle significantly affect the response statistics. The case study illustrates the applicability of the framework to comparative stability assessments of blast‐affected faulted rock slopes.