Influence of geometrical distribution of rock joints on deformational behavior of underground opening

Influence of Joint Dip Angle on Seismic Behaviors of Rock Foundation

“…The numerical results indicate that in the case of α = 60°, the total deformation of rock mass reaches the maximum under the combined action of the normal and tangential deformations of joints. The dynamic simulation results of this study have similar tendencies to the static simulation results reported by Wang 16) and Jiang,25) demonstrating that the joint dip angle has analogous effects on the deformation of rock masses under static and dynamic loading conditions. Figure 10 shows the change of the maximum horizontal stress with the joint dip angle at monitoring point M obtained from the DEM simulations, where positive values represent compressive stresses.…”

Fault-Related Instability Problems of Tunnels - The Host Rock Slip Criterion and Characteristics of the Tunneling-Induced Shear Displacements

“…And by substituting Equation 4 into Equation 5, the following equation is led to: denotes the criterion to evaluate whether rock would slide along the fault or not, and it is a local criterion, and not for the rock along the whole fault. For deep hard rock engineering, the fault cohesion was always assigned to be zero [21,27]. And for a simplified analysis, cohesion of fault is not considered ( According to Equation 6, lim  is dependent on the horizontal stress ratio k , dip angle of fault  and the distance between the fault plane and circular tunnel center d .…”

“…In the numerical model, rock was assumed to be elastic medium and fault followed Coulombslip criterion. Properties of rock mass were taken from the research of Jiang et al [27], and properties of fault were evaluated under the constant normal stress conditions [29,30]. In order to prevent the fault from opening, tensile strength of the fault was set at a relatively high value up to 10GPa.…”

Review: Mathematical expressions for estimating equivalent permeability of rock fracture networks

“…Since Mandelbrot (1982) introduced the concept of fractal dimension to represent the size distribution of the islands on the surface of the earth, fractal dimension has been rapidly utilized in many scientific aspects in geology and hydrology (e.g., Yu and Li 2001;Jiang et al 2006b;Wu and Yu 2007;Yun et al 2008). Researchers found that the distribution of pores in porous matrix show fractal properties (Yu and Cheng 2002;Yu et al 2005Yu et al , 2009Cai et al 2010;Miao et al 2014), and other researchers verified that the fracture distribution in fractured rock masses also exhibits fractal characteristics at both the macro-structural (i.e., geometry of fracture networks; Berkowitz and Hadad 1997;Babadagli 2001;Bagde et al 2002;Jiang et al 2006a;Kruhl 2013;Miao et al 2015a) and micro-structural (i.e., geometry of single fractures; Odling 1994; Kulatilake et al 1995;Babadagli and Develi 2003;Jiang et al 2006b;Askari and Ahmadi 2007;Li Y and Huang 2015;Babadagli et al 2015) levels.…”