Three-Dimensional Discrete Element Analysis of Jointed Rock Slope Stability Based on the Universal Elliptical Disc Model

A three-dimensional representation of the random distribution of fractures in rock masses, known as the discrete fracture network (DFN), is widely used to analyze the stability of jointed rock slopes. In this paper, a new framework for constructing three-dimensional DFN models in rock masses has been proposed to overcome the limitations of conventional circular or polygon-based models. The framework utilizes the universal elliptical disc (UED) model and integrates it with the discrete element method in 3DEC for the stability evaluation of jointed rock slopes. This paper starts by introducing the basic principles of the UED model. The procedures for constructing a three-dimensional DFN using the UED model is then outlined. In the present study, a case study of a rock slope in Zhejiang Province, China is used to demonstrate the implementation of the proposed framework. A comprehensive comparative study is conducted to investigate the impacts of several UED model parameters, including the ratio of major axis to minor axis and rotation angle, and discontinuity density, on the stability of rock slopes and compared to the conventional Baecher disc model. The results show that the framework can effectively integrate the UED model into 3DEC and provide a realistic representation of the three-dimensional DFN, leading to improved accuracy and efficiency in the stability evaluation of jointed rock slopes. The framework also shed light on the interactive effects of the UED model parameters and discontinuity density on the rock slope stability, providing a strong reference for using the UED model in constructing DFN models for rock slopes. Three-dimensional discrete fracture networks (DFNs) of rock masses are successfully constructed using the universal elliptical disc (UED) model.Python subroutines are developed in 3DEC to construct 3D DFNs using the UED model for improved discrete element analyses of jointed rock slopes.The effects of several characteristic parameters of the UED model on the stability of jointed rock slopes are investigated.Based on a key block model, the mechanisms underlying the relationship between jointed rock slope stability and fracture discontinuity are rigorously explained.The advantages of the UED model over the conventional Baecher disc model are comprehensively discussed based on a rock slope case study.