Experimental and FEM Study on Damaged Granitic Rock Using Second Rank Crack Tensor

Document Type : Research Article

Authors

Tarbiat Modares University

Abstract

Any investigative approach towards rock behavior will necessitate inherent deficiencies such as pores and cracks to be taken into consideration. One of the methodologies employed to study cracked rock is to consider an equivalent continuum as for the domain with defects which will lend flexibility to experimental and numerical schemes due to its seamless effects on the constitutive relationships, hence reducing computational costs as well as experimental restraints in the laboratory. A case in point in such approach is the crack tensor model which is based upon the idea to represent cracks’ size, orientation, and number density as one single entity through which proper geometric characterization of the in-situ rock is carried out. Following the introduction of crack tensor concept and its application in the technical literature, the current work focuses on the determination of second rank crack tensor using P-wave velocity measurements on damaged granite. The benefit of such approach is emphasized via its role in boosting the degree of accuracy of the numerical analysis code developed in Matlab that implements different compliance matrices for four different stages of loading. The calculation results showed promising trends in agreement with those of the experimental data. Apparently, more experimental procedure is required to improve results’ accuracy in projects for which fulfilling more stringent regulatory requirements is a must.

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References

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Amirkabir Journal of Civil Engineering
Volume 51, Issue 3
September and October 2019
Pages 415-424

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