DBPapers
DOI: 10.5593/SGEM2015/B12/S2.085

SHEAR STRENGTH OF ROCKS BY VISUAL ASSESSMENT

T. Ficker, D. Martisek
Friday 7 August 2015 by Libadmin2015

References: 15th International Multidisciplinary Scientific GeoConference SGEM 2015, www.sgem.org, SGEM2015 Conference Proceedings, ISBN 978-619-7105-32-2 / ISSN 1314-2704, June 18-24, 2015, Book1 Vol. 2, 641-648 pp

ABSTRACT
The present contribution deals with assessment of joint roughness coefficients of rock joints that play a crucial role when mechanical stabilities of large civil engineering structures (bridges, dams, tunnels) are evaluated. The roughness of rock joints essentially influences shear strength of these rock discontinuities and thus the assessment of the corresponding roughness coefficients is very important. In geotechnical practice a visual assessment based on ten two-dimensional profile standards is frequently used. The visual assessment is rather a subjective procedure but it could be replaced by computer assessment. The computer assessment would be especially desirable when the database of the standard profiles contains numerous items. The present contribution describes a computer procedure based on the Fourier formalism that is capable of recognizing similarity between investigated joint surfaces and those included into the software database. Such a computer procedure avoids subjectivity, offers a rigorous approach and is more comfortable especially in cases when the database will contain a large number of three-dimensional profiles.

Keywords: Rock joints, asperities, joint roughness coefficients, visual assessment, computer assessment, Fourier formalism, indicators of similarity, database of three-dimensional profiles.