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.
Rock Mechanics
M. B. Eslami Andargoli; K. Shahriar; A. Ramezanzadeh; K. Goshtasbi
Abstract
During the recent decades, the design and construction of underground spaces into rock salt have been particularly regarded for storing petroleum fluids, natural gas, and compressed air energy, and also for disposing nuclear and chemical wastes. The rock salt hosting such spaces will be subjected to ...
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During the recent decades, the design and construction of underground spaces into rock salt have been particularly regarded for storing petroleum fluids, natural gas, and compressed air energy, and also for disposing nuclear and chemical wastes. The rock salt hosting such spaces will be subjected to various types of monotonic/cyclic, short-term/long-term stresses during the construction and/or operation phases. On this basis, it is necessary to investigate the mechanical behavior of the rock salt under the effects of various monotonic short-term/long-term stresses. Out of the most important factors affecting the creep behavior of rock salt are the composition of minerals and size of the crystals comprising the rock salt, humidity, temperature, time, loading scheme, loading rate, strain rate, and loading period. In the present research work, a loading scheme and a loading period were considered. On this basis, in order to achieve a true understanding of the creep behavior of rock salt, it is necessary to determine the creeping coefficients via laboratory tests. Thus, twenty cylindrical (length to diameter ratio > 2) specimens of rock salt were prepared for conducting the creep tests. Two stepwise short-term creep tests (each at three stress levels, namely 4.4, 10.1, and 11.9 MPa, and 7.5, 12, and 17 MPa, respectively) and eighteen long-term creep tests (at six stress levels, namely 5.5, 7.5, 10, 12, 14, and 18 MPa) were conducted. Then, first, the creep coefficients were determined according to the Lubby 2 constitutive model. These coefficients were adjusted using the results of the creep tests. Afterwards, a creep experimental model was presented using linear and nonlinear regression of the creep test data. For validation of the results obtained, both the adjusted Lubby 2 constitutive model and the proposed experimental model were compared with the results obtained for the creep tests. Both models had fairly good agreements with the data for the creep tests at a determination factor of about 93%.
