Size dependency of intact rocks with high brittleness: A potential solution to eliminate secondary fractures in Brazilian test

H. Masoumi, M. Serati, D. J. Williams, H. Alehossein

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

10 Citations (Scopus)


The Brazilian test is one of the most established techniques used for indirect measurement of rock tensile strength. When the test is applied to soft to medium strength rocks, the rupture mechanism is always through the formation of a single diametrical crack initiated at the centre of the disc, where the induced tensile stress is the maximum. However, when applied to disc specimens of harder, stiffer and brittle rocks, secondary shear fractures often interfere adversely with the diametrical (characteristic) tensile crack in the Brazilian test. To prevent such undesirable shear cracking, a series of Brazilian tests on specimens of different sizes was carried out with four different brittle rocks, including granite, basalt and two types of monzonite. From the results, it is concluded that the problem associated with the undesirable shear failure developed in the vicinity of the contact points can be effectively eliminated through a change in the size of the disc in the Brazilian test.

Original languageEnglish
Title of host publication51st US Rock Mechanics / Geomechanics Symposium 2017
EditorsHaiyang Huang
Place of PublicationAlexandria VA USA
PublisherAmerican Rock Mechanics Association (ARMA)
Number of pages4
ISBN (Electronic)9781510857582
Publication statusPublished - 1 Jan 2017
Externally publishedYes
EventUS Rock Mechanics / Geomechanics Symposium 2017 - San Francisco, United States of America
Duration: 25 Jun 201728 Jun 2017
Conference number: 51st


ConferenceUS Rock Mechanics / Geomechanics Symposium 2017
Country/TerritoryUnited States of America
CitySan Francisco
Internet address

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