A Rough Discrete Fracture Network Model for Geometrical Modeling of Jointed Rock Masses and the Anisotropic Behaviour

Abstract

The geometry of the joint determines the mechanical properties of the rock mass and is one of the key factors affecting the failure mode of surrounding rock masses. In this paper, a new rough discrete fractures network (RDFN) characterization method based on the Fourier transform method was proposed. The unified characterization of the complex geometric fracture network was achieved by changing the different Fourier series values, which further improved the characterization method of the RDFN model. A discrete element numerical calculation model of the complex RDFN model was established by combining MATLAB with PFC code. Numerical simulation of the anisotropic mechanical properties was performed for the RDFN model with a complex joint network. Based on the results, the geometry of the joint network has a significant influence on the strength and failure patterns of jointed rock masses. The failure modes of the opening are highly affected by the orientation of the fracture sets. The existence of the rough fracture sets could influence the failure area of different excavation situations. The study findings provide a new characterization method for the RDFN model and a new characterization approach for stability analysis of complex jointed rock masses.

The Confinement-Affected Strength Variety of Anisotropic Rock Mass

“… The analytical and experimental strength of anisotropic dolomitic limestone (modified based on [ 34 ]). ( a – d ) represent the results under triaxial compression at different confining pressure ( ) of 20, 40, 60, 80 MPa, respectively.…”

“…Extensive compression tests have been put forward to explore the strength and failure features of various anisotropic rock masses at uniaxial and triaxial compression conditions in the laboratory, e.g., slate [ 18 , 19 , 20 ], schist [ 13 , 20 , 21 , 22 , 23 , 24 ], phyllite [ 13 , 25 ], marble [ 13 , 23 ], sandstone [ 3 ], shale [ 26 , 27 , 28 ], limestone [ 28 , 29 , 30 ], mudrock [ 31 ], columnar basalt [ 32 ], and artificially anisotropic rock specimens [ 3 , 33 ]. Numerical studies have also been conducted to investigate the mechanical behavior of anisotropic rock mass intrinsically [ 12 , 34 ]. These effective studies reflect that the deformation and strength properties are largely dominated by the angle between the normal anisotropic structural plane and the direction of minimum principal stress ( ).…”

Research on Water Pressure Distribution Characteristics and Lining Safety Evaluation of Deep Shaft in Water-Rich, Large, Fractured Granite Stratum

“…Gottron., S. Nadimi., etc., show that this model is suitable for rock masses with small fracture density and large fracture size [14][15][16][17]. The above mathematical model can effectively simulate fractured rock mass at the technical level, and the simulation of fractured rock mass depends not only on the selection of model, but also on the construction of fracture network.…”