Assessing the empirical correlations between engineering properties and P wave velocity of some sedimentary rock samples
- PDF / 11,981,914 Bytes
- 17 Pages / 595.276 x 790.866 pts Page_size
- 93 Downloads / 170 Views
ORIGINAL PAPER
Assessing the empirical correlations between engineering properties and P wave velocity of some sedimentary rock samples from Damghan, northern Iran Reza Khajevand 1 & Davood Fereidooni 1 Received: 24 May 2017 / Accepted: 9 August 2018 # Saudi Society for Geosciences 2018
Abstract In the present research, engineering properties of some sedimentary rock samples were measured to assess the correlations between P wave velocity and physical, index, and mechanical properties. The physical properties include dry and saturated unit weights, porosity, and water absorption. The index properties contain Schmidt rebound hardness and slake-durability index. The mechanical properties include uniaxial compressive strength, point load index, Brazilian tensile strength, and block punch strength. For this purpose, a comprehensive laboratory testing program was conducted after collecting 15 various sedimentary rock samples of four rock types from northwestern parts of Damghan, northern Iran. In the following, empirical equations were developed by using regression analyses between P wave velocity and the measured properties. The obtained results showed that all of the properties have strongly correlated to P wave velocity. Hereof, the relationships between P wave velocity and porosity and water absorption were inverse linear. But, P wave velocity has direct linear correlations with the other properties. Prepared contour maps indicated that P wave velocity is more affected by porosity of the rocks. The curves with the 45° line (y = x) were extracted for evaluating the validity degree of concluded empirical equations which approved approximately close relationships between P wave velocity and the measured properties. Keywords Rock sample . P wave velocity . Engineering properties . Regression analysis . Empirical equation
Introduction Estimating physical and mechanical properties of rocks is considered to be the most important components in different engineering projects such as underground structures, tunnels, dams, rock foundations, rock slopes, and selection of construction materials. Particularly, rock strength measurement is considered to be necessary for the design of rock structures, as well as for the strength classification of rock materials. Strength behavior of intact rock materials is determined in the laboratory from core specimens according to ISRM (2007) suggested methods. But preparation of specimens with particular size for testing based on standards due to difficulties in strength determination particularly for weak, foliated, and closely jointed rocks. Another aspect of the conventional tests is the amount
* Davood Fereidooni [email protected] 1
School of Earth Sciences, Damghan University, Damghan, Semnan, Iran
of time, expensive testing apparatuses, and laboratory requirements. These difficulties motivated investigators to develop simple rock strength indexes and non-destructive tests or empirical equations for predicting strength and deformability behavior from other rock properties which
Data Loading...
