Abstract
We investigate how a highly elliptical and mechanically rigid clast embedded in an infinite rock mass respond to the far-field stresses. The numerical analysis is carried out on elliptical clasts with aspect ratios ranging from 13.5 to 58.5, oriented at a right angle to the maximum far-field stress. A 2D plane strain model has been adopted to decipher the states of stress inside elliptical clasts. We argue that the tensile stress within the clasts gets enhanced and develops systematic mode-I (tensile) fractures within it as the far-field stress increases. We conclude that the intra-clast tensile stress decreases with increasing clast ellipticity, i.e., tensile fractures develop more easily within clasts with higher aspect ratios (~>20) while a higher far field tensile stress is required to fracture clasts with lower aspect ratios. We also interpret that stress enhancement is independent of the clast area and inter-focii distance of the clast, whilst the aspect ratio of the clast is found to be crucial for the development of tensile fractures within the elliptical clast for a constant material property.
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ACKNOWLEDGMENTS
The author Paramita Das acknowledges Indian Statistical Institute for Visiting Scientist research grant. She thanks Dr. Shiladri S. Das (Indian Statistical Institute, Kolkata, India) for providing the logistic supports. The authors are grateful to Sreyashi Bhowmick (Tel Aviv University International, Tel Aviv, Israel). The authors are thankful to anonymous reviewers for helpful comments and to Editor M.N. Shoupletsova (Geological Institute of Russian Academy of Sciences, Moscow, Russia) for thorough editing the manuscript.
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This work was supported by Indian Statistical Institute research grant to Tridib Kumar Mondal.
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Das, P., Acharyya, S.S., Mondal, T.K. et al. Evaluating Tensile Fractures in Rigid Clasts with Very High Aspect Ratio. Geotecton. (2024). https://doi.org/10.1134/S0016852124700080
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DOI: https://doi.org/10.1134/S0016852124700080