Estimation of rock strength from quantitative assessment of rock texture
CA Ozturk, E Nasuf, S Kahraman
The compressive strength of rock (sc) has an important effect on design of
structures in rock engineering. Compressive strength can be determined in
the laboratory using the uniaxial compressive strength (UCS) test. Some
other index tests, such as the point load test, are also used, particularly
when suitable samples for UCS are not available. The quantification of rock
texture has introduced a new method in rock engineering for estimating the
mechanical and physical properties of rock materials from microscopic
investigations. The aim of this study is to quantify rock texture to estimate
rock strength from the texture coefficient (TC), which is determined from a
statistical assessment of thin section images. Rock texture is quantified by
twelve different images from a single thin section to increase the reliability
of texture analysis. A data-set is prepared to investigate correlations
between TC and sc. The statistical correlations are computed after
classifying of the rock samples based on their lithology as well as grain
features. Equations derived based on the results of this study are used to
predict the approximate value of compressive strength from the texture
coefficient. This method is particularly useful for preliminary studies in
rock engineering projects prior to detailed site investigation.
Keywords: rock engineering, compressive strength, statistical correlation, grain
features, texture coefficient.