Numerical Analysis for the Progressive Failure of Binary-Medium Interface under Shearing

Abstract

Binary-medium specimens were fabricated using the particle flow code, and the shear strength, dilatancy, and failure behavior of the binary-medium specimens with different bond strength ratios (0.25, 0.5, 0.75, and 1.0) under different normal stresses were studied. Numerical results show that the bond strength ratio and normal stresses considerably influence the shear strengths of binary-medium interface. Shear strength increases as the bond strength ratio and normal stress increase. e dilation of interfaces with high bond strength ratios is more evident than those of interfaces with lower bond strength ratios, and the curves for the high bond strength ratio exhibit remarkable fluctuations during the residual stage. At increased normal stress and bond strength ratio, the peak dilation angle shows decreasing and increasing trends successively. In this study, the specimens exhibited three kinds of failure modes. In mode II, the sawtooth experienced shear failure, but some tensile cracks appeared on the interface of the binarymedium. In mode III, no sawtooth was cut off, indicating tensile failure on the interface. At a low bond strength ratio, damage or failure is mostly concentrated in the upper part of the model. Failure parts gradually transfer to the lower part of the model when the bond strength ratio and normal stress increase. Furthermore, evident tensile cracks occur on the interface. When the bond strength ratio reaches 1.0, the failure mode of the specimen gradually transforms from sheared-off failure to chip-off failure. e number of microcracks in the specimens indicates that the lower the bond strength ratio, the more severe the damage on the specimens.

Crack Initiation, Propagation, and Failure Characteristics of Jointed Rock or Rock‐Like Specimens: A Review

“…In recent years, many numerical methods have been widely used in rock mechanics and rock engineering. ese include the FEM or XFEM [144][145][146][147][148][149][150][151], DDA [152][153][154][155], NMM [156][157][158], smoothed particle hydrodynamics [159][160][161][162], and PFC [17,[163][164][165][166][167][168][169][170][171][172]. Overall, most of the numerical results show good agreement with experimental results.…”

An empirical statistical constitutive relationship for rock joint shearing considering scale effect

“…The Lemaitre model assumes that the damaged part cannot bear the load, which is evidently inconsistent with the residual strength properties of the rock material. In fact, the damaged material can also bear a certain load [45][46][47][48], that is, the nominal stress σ suffered by the rock and soil material is shared by two parts.…”

Numerical Analysis for Shear Behavior of Binary Interfaces under Different Bonded Conditions

“…Ghazvinian, Taghichian [14] carried out simulations of the shear mechanical behavior of a weak interlayer between two rocks with high strength differences and proposed an equation on the relationship between the roughness coefficient parameter and surface statistical fractal parameters. Cao, Tang [15] investigated the shear strength, shear expansion, and damage behavior of binary interfacial specimens with different bond strength ratios under different normal stresses. Yan, Long [16] found that the shear stress at the mortar-rock interface was much smaller than that at the bolt-mortar interface for bolted rock slopes containing weak interlayers, and the shear stress distribution and the debonding damage process at the bolted interface of slopes under seismic action were obtained.…”