Shahrood University of Technology Journal of Mining and Environment 2251-8592 11 3 2020 07 01 On Applicability of Some Indirect Tests for Estimation of Tensile Strength of Anisotropic Rocks 711 720 1696 10.22044/jme.2020.9220.1813 EN F. Rastegar Rock Mechanics Division, School of Engineering, Tarbiat Modares University, Tehran, Iran H. R. Nejati Rock Mechanics Division, School of Engineering, Tarbiat Modares University, Tehran, Iran A. Ghazvinian Rock Mechanics Division, School of Engineering, Tarbiat Modares University, Tehran, Iran M. R. Hadei Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran A. Nazerigivi Faculty of Civil Engineering, University of Minho, Braga, Portugal Journal Article 2019 12 23 The tensile strength of rocks plays a noteworthy role in their failure mechanism, and its determination can be beneficial in optimizing the design of the rock structures. Schistose rocks due to their inherent anisotropy in different foliation directions show a diverse strength at each direction. The purpose of this work was to compare and assess the tensile strength of phyllite, which was obtained in direct and indirect tensile tests in different foliation directions. To this end, several phyllite specimens with different foliation angles (0º, 30º, 45º, 60º, and 90º) related to the loading axis (β) were prepared. Finally, the direct tensile test, diametrical and axial point load tests, Brazilian test, and Schmidt hammer test were conducted on 188 samples. The results of the experimental tests revealed that the maximum and minimum tensile strengths in direct tensile testing tension were directly related to the angles of 0º and 90º. Also it was observed that the Brazilian tensile strength overestimated the tensile strength. Furthermore, an exponential correlation was introduced between the direct tensile strength and the Brazilian tensile strength. https://jme.shahroodut.ac.ir/article_1696_0930a1df4712cf837241d76bc34ff88d.pdf