Improvements in the three-component borehole deformation gage and overcoring techniques.
Hooker-VE; Aggson-JR; Bickel-DL; Duvall-WI
NTIS: PB 234 137, 1974; :1-29
This Bureau of Mines report summarizes the results of modifications in the borehole deformation gage design and subsequent changes in the overcoring techniques. Modifications in the borehole deformation gage have greatly improved the creep characteristics and enhanced the versatility of the gage. In situ field tests in competent rock near St. Cloud, Minnesota, provided sufficient data to compare the reliability between gages and new techniques in obtaining good engineering estimates of stresses. Near-surface horizontal stresses at the test sites are compressive and biaxial in nature.
Mining-industry; Equipment-design; In-situ-mining; Equipment-reliability
IH; Report of Investigations
NTIS Accession No.
NTIS: PB 234 137