A proposed up-scaling based micromechanical damage model for brittle rock and its validation in the laboratory scale

Document Type : research - paper

Authors

1 amirkabir university of technology

2 Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Polytechic of Tehran)

3 Science and Research Branch of the Islamic Azad University

4 Tarbiat Modares University

Abstract

Understanding the non-elastic behavior of demolished rock in the rock structures, especially after maximum resistance, is required for the stability analysis of the rocky structure. Mechanical failure theory is a method for analyzing the behavior of rocks, especially after maximum resistance. Methods based on fracture mechanics consider the behavior of the rock well, such as reducing load capacity after maximum resistance and elastic rigidity. In this research, a microstructural failure model for open and closed friction microcrack is considered, taking into account the coupling between frictional slip and damage. Therefore, the basic concepts of mechanical mechanics failure are presented first. To calculate the effect tensor, the Ponte-Castaneda and Willis (1995) homogenization pattern has been used. Then, the formulation of this model was coded in FLAC software environment and the micromechanics damage behavior model developed in the FLAC software environment was called as a new behavioral model. In order to use the developed model and validate it on a laboratory scale, a axial compressive strength test on limestone was used as the basis, and its results with acceptable numerical model were acceptable.

Keywords


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