Effect of Confining Pressure on Is(50) Obtained by Point Load Test

Sarfarazi, V.; Asgari, K.

doi:10.22044/jme.2021.10918.2070

Document Type : Original Research Paper

Authors

V. Sarfarazi ¹
K. Asgari ²

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

² Research Scholar, Department of Mining Engineering, Shahid Bahonar University of Kerman, Kerman, Iran

https://doi.org/10.22044/jme.2021.10918.2070

Abstract

In this investigation, the impact of confining pressure on the tensile strength obtained by point load test (PLT) is examined by particle flow code in two dimensions. In this regard, at first, a numerical model is calibrated using the Brazilian experimental test results. The tensile strength of the model material is equal to 2.5 MPa. Secondly, PLT is performed on the numerical models with dimension of 15 cm × 50 cm. The rectangular models are tested by PLT under the presence of the confining pressure. The loading rate is 0.001 mm/min, confining that the pressure is changed with the 13 different values of 0 MPa, 0.002 MPa, 1MPa, 1.5 MPa, 2 MPa, 2.5 MPa, 3MPa, 3.5 MPa, 4 MPa, 5MPa, 6 MPa, 9 MPa, and 11 MPa. The results obtained show that the vertical tensile crack develops through the model under a low confining pressure, while several shear bands are developed in the models under a high confining pressure. The number of shear cracks is augmented by augmenting the confining pressure. Is(50) is the augment by augmenting the confining pressure. Also a new criterion is rendered in order to determine Is(50) based on the confining pressure.

Keywords

20.1001.1.22518592.2021.12.4.8.9

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Journal of Mining and Environment

Effect of Confining Pressure on Is(50) Obtained by Point Load Test

References

References

Volume 12, Issue 4
October 2021
Pages 1019-1028

Effect of Confining Pressure on Is(50) Obtained by Point Load Test

References

References

Volume 12, Issue 4October 2021Pages 1019-1028

Volume 12, Issue 4
October 2021
Pages 1019-1028