Definition - What does Core Shovel mean?
Core shovel is used in overcoring operations for retrieving cores from the borehole. Other equipment required are core breaking wedge and core puller. The core is removed by sliding the end of the core shovel under the core and pulling it out. Overcoring is done in a pilot hole fitted with a strain gauge, beginning at the borehole diameter. Radial displacement is recorded by the strain gauge and used for estimating stress for various geological conditions.
Trenchlesspedia explains Core Shovel
A core breaker, core shovel, and core puller are used as part of the drilling equipment apparatus used to drill the borehole for in-situ stress testing. In situ stress is of great importance in geotechnical engineering because they form the basis for conducting sub-surface drilling operations. Identifying high risk zones based on stress field is essential for engineers to implement appropriate control methods to prevent failure and loss.
Hydraulic fracturing - conventional hydraulic fracturing and hydraulic tests on pre-existing fractures (HTPF), overcoring - displacement measurements, without pilot holes, borehole breakout, flat jack, etc. are some of the methods used to determine in-situ stress.