Arabnia Ali, Akbardoost Javad, Cicero Sergio, Torabi Ali Reza
Department of Mechanical Engineering, Faculty of Engineering, Kharazmi University, Mofatteh Avenue, Tehran P.O. Box 15719-14911, Iran.
LADICIM (Laboratory of Materials Science and Engineering), E.T.S. de Ingenieros de Caminos, Canales y Puertos, Universidad de Cantabria, Av/Los Castros 44, 39005 Santander, Spain.
Materials (Basel). 2022 Dec 8;15(24):8779. doi: 10.3390/ma15248779.
This work aims to assess both experimentally and analytically the fracture behavior of rock specimens containing sharp V-notches (SV-notches) subjected to mixed mode I/II loading. To this end, firstly, several mixed mode fracture tests were conducted on Brazilian disk specimens weakened by an SV-notch (SVNBD sample), performed in their corresponding center and with various notch opening angles. Secondly, the fracture resistance of the tested samples was predicted using a criterion named MTS-FEM. This approach is based on the maximum tangential stress (MTS) criterion, in which the tangential stress is determined from the finite element method (FEM). Additionally, in the present research, the required critical distance is calculated directly from finite element analyses performed on cracked samples. Comparing the experimental results and the analytical predictions, it is shown that the fracture curves obtained from the MTS-FEM criterion are in agreement with the experimental results. These results are achieved without the need for the calculation of stress series expansion coefficients, as an additional advantage of the proposed approach.
本研究旨在通过实验和分析手段评估含尖锐 V 型切口（SV 切口）的岩石试样在 I/II 混合模式加载下的断裂行为。为此，首先，对通过 SV 切口削弱的巴西圆盘试样（SVNBD 试样）进行了若干混合模式断裂试验，这些试验在试样相应中心进行，且具有不同的切口张开角度。其次，使用名为 MTS - FEM 的准则预测测试试样的抗断裂能力。该方法基于最大切向应力（MTS）准则，其中切向应力由有限元方法（FEM）确定。此外，在本研究中，所需的临界距离直接从对含裂纹试样进行的有限元分析中计算得出。通过比较实验结果和分析预测结果表明，从 MTS - FEM 准则获得的断裂曲线与实验结果一致。作为所提方法的一个额外优点，这些结果无需计算应力级数展开系数即可获得。
