Comparison of fracture toughness measurement techniques in brittle rocks.
Published: 2004
Language: eng
Number of pages: 112
Description: The fracture toughness values of rocks have been found to have large variation even after the standardization of the fracture toughness measurement techniques by International Society for Rock Mechanics (ISRM). A comprehensive testing program was devised to investigate the ISRM suggested fracture toughness measurement techniques using three rock types. The objective was to determine the best suggested method for determining fracture toughness of rocks and to determine the consistency of the fracture toughness values for the same rock type.Detailed statistical analyses were conducted to analyse the test data. It was found that the fracture toughness values were fairly consistent provided special care was taken in selecting specimen size and handling anisotropy issues. The major difference in the fracture toughness values from Chevron Bend 'CB' and Cracked Chevron Notch Brazilian Disc 'CCNBD' methods was due to an error in the formula used for calculation in the CCNBD case. The suggested improvement of empirical specimen size requirement equation, used to estimate the minimum required diameter of specimen in the CB test, worked fine. This was not so for the improvement in dimensionless parameter calculation, used for calculating fracture toughness values from the CCNBD test.
Notes: Adviser:  Bibhu Mohanty.

Thesis (M.A.Sc.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Masters Abstracts International, Volume: 43-03, page: 0917.

MICR copy on microfiche (2 microfiches).