Issue 53

Y.D. Shou et alii, Frattura ed Integrità Strutturale, 53 (2020) 434-445; DOI: 10.3221/IGF-ESIS.53.34 437 axial strain 1  is 3.583% and the corresponding transverse strain 3  is -1.872% when the confining stress is 15 MPa. The elastic modulus of coal-rock is 957 MPa and the Poisson's ratio of coal-rock is 0.36. Figure 3: The deviatoric stress versus axial strain under the confining pressure of 0 MPa. Figure 4: The deviatoric stress 1 3   − versus axial strain 1  and transverse strain 3  under the confining pressure of 5 MPa. Figure 5: The deviatoric stress 1 3   − versus axial strain 1  and transverse strain 3  under the confining pressure of 10 MPa.