Issue 75

R. Ince et alii, Fracture and Structural Integrity, 75 (20YY) 435-462; DOI: 10.3221/IGF-ESIS.75.30

Figure 13: Implementation of TPM to beams and SNCB specimens tested in this study.

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onlinear fracture models, frequently applied in the examination of concrete fracture, were utilized in this study to evaluate the fracture quantities of quasi-brittle SNDB and SNCB specimens made from rock materials. The results of this investigation are summarized below: 1) The examination of rock SNDB specimens with a depth/diameter ratio of 0.5, documented in the literature, utilized both the compliance method and the peak load method, revealing a significant correlation between the two approaches. This has previously been observed in other quasi-brittle materials such as concrete and asphalt concrete. It is emphasized that the most important advantage of the peak-load method is that it does not require sophisticated test equipment, unlike the compliance method, to determine the fracture quantities of the materials. 2) Another statistical comparison based on the t-test and the F-test was conducted for the compliance method based on the TPM and the numerical method based on the FEA proposed by Tutluoglu and Keles [14]. It was revealed that there was a significant correlation between the two methods according to both the means and the variances. 3) The fracture tests of comparative tests on beams and SNCB specimens reveal that the fracture quantities of rocks based on the TPM and the double- K model can easily be estimated using SNCB specimen tests, so specimens of differing sizes are unnecessary. On the other hand, the LEFM expressions derived for cubical specimens containing an edge notch can also be used for square prismatic specimens containing an edge notch subjected to a bending load. 4) The primary benefits of cylindrical and cubical specimens containing an edge notch, examined in this study, are their lightness and compactness compared to beams. Furthermore, in the determination of the fracture quantities of rocks, the use of these specimens, facilitated by core drilling, enables the extraction of materials from rock formations, providing significant benefits. 5) The CCI technique is not as commonly used as the J-integral approach and is not integrated into many commercial finite element method software. However, the implementation of the CCI technique is notably more

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