Estimation of strength anisotropy using the point-load test

doi:10.1016/0148-9062(83)90942-7

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts

Volume 20, Issue 4, August 1983, Pages 181-187

International Journa...

https://doi.org/10.1016/0148-9062(83)90942-7 Get rights and content

Abstract

As most rocks are of an anisotropic nature, the measurement of the ratio between the maximum and minimum strength, i.e. the strength anisotropy, is of general interest. To measure the strength anisotropy by the uniaxial compression test, core specimens drilled in different directions are needed. With the point-load test it is possible to obtain the strength anisotropy on one core only by first using the diametral test and then applying axial tests on the core pieces. The paper describes results from tests performed on 33 different rocks to find a diagram that could be used to compensate for the influence of size and shape in the axial test. Cores were drilled both parallel and normal to bedding or foliation planes. Analyses of the results show that the most reliable strength index is obtained when cores are drilled normal or near normal to weakness planes. The paper concludes with a suggested procedure for measurements and calculations.

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Estimation of strength anisotropy using the point-load test

Abstract

Int. J. Rock Mech. Min. Sci. & Geomech. Abstr.

Int. J. Rock Mech. Min Sci. & Geomech. Abstr.

Int. J. Rock Mech. Min. Sci. & Geomech. Abstr.

Anisotropy of a schistose gneiss

Experimental study of shear failure in anisotropic rocks

Bull. Geol. Soc. Am.

Methods and results from testing of rocks for road construction

Medd. No. 8

Strength anisotropy of rocks

The point-load strength test

Int. J. Rock Mech. Min. Sci.

Suggested methods for determining the point-load strength index