Standard Test Method for Determination of In Situ Stress in Rock Mass by Overcoring Method-USBM Borehole Deformation Gage

1.1 This test method covers the determination of the ambient local stresses in a rock mass and the equipment required to perform in situ stress tests using a three-component borehole deformation gage (BDG). The test procedure and method of data reduction are described, including the theoretical basis and assumptions involved in the calculations. A section is included on troubleshooting equipment malfunctions.

Note 1—The gage used in this test method is commonly referred to as a USBM gage (U.S. Bureau of Mines three-component borehole deformation gage).

1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are provided for information only.

1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.