Abstract
Strain measurements are conducted on drill rods to investigate the rock drillability for percussion drilling. When the length of drill rod with a uniform cross section is short, the method of two-point strain measurement must be employed to separate an incident wave and a reflective wave.Strain measurements on two types of short drill rod (rod 1 and rod 2) using the two-point method are described. Results from experimental measurements using rod 1 include the following: (1) An accurate analysis of strain at the evaluation point could not be obtained when the 4-gage method was applied. On the other hand, accurate strain measurements were obtained using the 2-gage method (opposite side) . (2) Measurements using strain gages of length 5 mm were more suitable for the analysis of strain at the evaluation point than measurements using 2-mm strain gages. Results from tests to measure strain in two parts of rod 2 (part S and part F) include the following: (3) A complete measurement of a strain wave could not be obtained at part S, even using the 2-gage method. However, approximately two-thirds of the wave could be analyzed correctly. (4) For part F, an almost complete measurement of the strain wave was obtained using the 2-gage method. In addition, the similarity of the strain waves of part S and part F was confirmed.Finally, based on the results for rod 2, the complete percussion energy per hammer blow for part S was estimated.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
