Rock Mechanics
amir rezaei; vahab sarfarazi; mohammad fatehi marji; mohammad omidi manesh
Abstract
This study provides an in-depth examination of the failure characteristics of rock salt samples subjected to punch shear testing, emphasizing the analysis of fracture processes and the material’s mechanical response. Given the diverse industrial applications of rock salt, the need for more detailed ...
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This study provides an in-depth examination of the failure characteristics of rock salt samples subjected to punch shear testing, emphasizing the analysis of fracture processes and the material’s mechanical response. Given the diverse industrial applications of rock salt, the need for more detailed studies in this field is evident. The study employs an integrated approach combining practical experiments and numerical simulations using PFC2D software. The results reveal that the failure response of rock salt is governed by critical factors such as the loading rate and the material’s inherent mechanical properties. Laboratory observations indicate that fractures primarily initiate from structurally weak zones, with stress concentration at contact areas being the main cause of tensile-shear failures in the samples. The findings of this study can serve as a foundation for establishing novel quality evaluation criteria for rock salt, underscoring the need for continued research efforts to improve safety and performance in related engineering applications.
Amir Rezaei; Vahab Sarfarazi; Nima Babanouri; Mohammad Omidi manesh; Shirin Jahanmiri
Abstract
Non-persistent joints are geologic occurrences in rocks that weaken pillars because they are present within them. Using practical tests and numerical models, it has been determined how edge notches affect the way pillars break. Gypsum samples that are notched and have dimensions of 70 mm by 70 mm by ...
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Non-persistent joints are geologic occurrences in rocks that weaken pillars because they are present within them. Using practical tests and numerical models, it has been determined how edge notches affect the way pillars break. Gypsum samples that are notched and have dimensions of 70 mm by 70 mm by 50 mm are created. Gypsum's Young modulus, Poisson ratio, compressive strength, and tensile strength are 5.5 GPa, 0.27, 8 MPa, and 1.1 MPa, respectively. 10-, 20-, and 30-degree notch angles are used. The model receives an axial stress at a rate of 0.05 mm/min. On a rock pillar, numerical simulation is carried out concurrently with an experimental test. The findings indicate that the joint angle is mostly responsible for the failure process. The fracture pattern and failure mechanism of the pillars are connected to the compressive strengths of the specimens. At the notch points, two significant splitting tensile fractures spread vertically until coalescing with the top and lower boundaries of the models. On the left and right sides of the pillar, two rock columns are also taken out. The overall number of cracks rises as sample loading increases. The model's deformation at the start of loading reflect a linear elastic behavior, and the number of fractures steadily grows. When the number of cracks increases, the curve becomes non-linear, and the force being applied peaks. When the sample can no longer tolerate the applied force, a dramatic stress decrease occurs. The macro-failure over the whole model is what leads to the greater stress decrease following the peak load. In actuality, the reduced stress reduction is accompanied by more overall fractures. Similar findings are shown in both the experimental testing and numerical modeling.
