00000nam 2200000za 4500 9.866897 CaOODSP 20221107162153 m o d f cr ||||||||||| 190110t19771978onca ob f000 0 eng d 066010007X (print) CaOODSP eng eng fre n-cn--- M38-13/78-11E-PDF M38-13/78-11 Herget, G. Equipment and procedures to determine ground stresses in a single drill hole [electronic resource] / G. Herget, P. Miles and W. Zawadski. Ottawa : CANMET, Energy, Mines and Resources Canada, 1977, c1978. iv, 22 p. : ill. CANMET report ; 78-11 Cover title. "September 1977." "Minerals Research Program, Mining Research Laboratories." Digitized edition from print [produced by Natural Resources Canada]. Includes bibliographical references (p. 16). "Determination of ground stress is necessary for applying strength testing and failure theories to the rational design of excavations in rock. The major expense item for ground stress determination is the drilling of holes to install equipment and for overcoring. The triaxial strain cell developed by CSIR in South Africa has the advantage that only one drill hole is necessary to determine the complete ground stress tensor. Initial experience showed, however, that the rate of success was lower using the triaxial equipment than when using the biaxial or doorstopper equipment which requires three drill holes to obtain the complete stress tensor. Experience from field tests has resulted in modifying the triaxial stress determination equipment and testing procedures. These are described for the benefit of potential users"--Introd., p. 1. Includes summary in French. Rock pressure--Measurement--Equipment and supplies Drilling and boring Mining engineering Miles, P. Zawadski, W. Canada. Energy, Mines and Resources Canada. Canada Centre for Mineral and Energy Technology. Minerals Research Program (Canada) Mining Research Laboratories (Canada) CANMET report ; 78-11. (CaOODSP)9.852792 PDF 2.16 MB https://publications.gc.ca/collections/collection_2019/rncan-nrcan/m38-13/M38-13-78-11-eng.pdf 307127