Document Type : Original Research Paper

Authors

1 Department of Mining Engineering, Hamedan University of Technology, Hamedan, Iran,

2 Department of Mining Engineering, Higher Education Complex of Zarand, Shahid Bahonar University of Kerman, Kerman, Iran.

3 School of Civil Engineering and Transportation, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China

4 Department of Mining Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran, Iran

5 Department of Geology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, Iran,

10.22044/jme.2026.17350.3438

Abstract

In this research, samples of bi-material notch discs were created and examined in the laboratory to investigate their mechanisms of indirect tensile failure. Brazilian tensile strength tests were conducted to determine the mechanical properties of these samples under a loading rate of 0.016 mm/s. The discs were designed with a central notch and were made from two materials: concrete and gypsum. Gypsum (Material 1) was placed at the center (core), while concrete (Material 2) was used to form a peripheral strip (ring) around this core. The core diameter and ring thickness were varied, resulting in a total of 21 specimens that were prepared and subjected to axial loading during testing. To support the experimental results, the Particle Flow Code (PFC) was utilized to simulate the tests. It was observed that both the notch dimensions and the choice of materials significantly influenced the mechanical behavior and fracture characteristics of anisotropic rocks. Furthermore, based on the results obtained from the laboratory samples and the modeling of these samples using PFC software, strong agreement was achieved regarding crack growth behavior. In addition, a comprehensive study was conducted on the samples through numerical modeling, which included the distribution of bond forces and Rosette diagrams, as well as crack growth patterns.

Keywords

Main Subjects

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