Predicting of uniaxial compressive strength of carbonate rocks using simple test methods

A strong laboratory database of engineering properties of rocks is very useful for geotechnical engineering applications. In the most of engineering geological and rock engineering applications, uniaxial compressive strength (UCS) of rocks is the most widely used design test. However, in some cases it can be quite difficult, time consuming and expensive to prepare specimens and to conduct this test. As an alternative, it can be used empirical or analytical relationships among various physical and mechanical strength properties of materials to estimate the required engineering properties of rocks. For these reasons, simple test methods such as porosity and ultrasonic sonic velocity test are used widely. These simple tests have been world widely used to estimate the UCS of rocks, because of their rapidity, simplicity, portability, low cost, non-destructiveness and easiness in both specimen preparation and test conduction.The aim of this study is to establish some statistical correlations between these simple test methods and UCS. Simple and multiple regression modeling were conducted to obtain equations, required for predicting UCS of rocks and 16 empirical equations are summarized that relate unconfined compressive strength of carbonate rocks (travertine, onix and limestone) to physical properties such as ultrasonic velocity and porosity. UCS values obtained from regression analysis and UCS tests are compared and the results are discussed.