Drilled Core Specimen Testing Method for Determination of Tensile Strength Values of Rock Materials

  • Eren Komurlu Giresun University Civil Engimeering Department
  • Serhat Demir Karadeniz Technical University Civil Engineering Department

Abstract

In this study, a new direct tensile strength determination method of drilled core specimen testing was investigated with numerical and experimental studies. Effect of different drill diameters of holes of the rock specimens was analysed to assess the ideal drill-hole design. The aim of drilling process is decreasing the failure load and stress concentration at the adhesive part to prevent invalid failures. Drilled specimens were determined to fail due to the start of cracking under the condition of uniaxial tensile stress distribution at sidewalls of holes. It was found that drill bits with the diameter of 11 mm is usable for a practical specimen drilling process to make a significant decrease in the failure load of the core specimens with the NX size (@54 mm) diameter. According to the results obtained from numerical and experimental analyses, an equation was suggested to determine uniaxial tensile strength values of drilled core specimens with the hole diameter of 11 mm.

Keywords: tensile strength of rock materials, rock testing, experimental rock mechanics, finite element analyses
Published online
2018-09-14
How to Cite
Komurlu, E., & Demir, S. Drilled Core Specimen Testing Method for Determination of Tensile Strength Values of Rock Materials. Periodica Polytechnica Civil Engineering. https://doi.org/10.3311/PPci.12524
Section
Research Article