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Understanding the hydraulic pressure cell.

Heasley KA

Proceedings of the 30th U S Symposium on Rock Mechanics as a Guide for Efficient Utilization of Natural Resources. Balkema, 1989 Jan; :485-492

10008614

Numerous different instruments and techniques have been developed for the purpose of measuring rock stress and stress changes around excavations. The interpretation of the output from many of these instruments has often been problematic. This U.S. Bureau of Mines paper covers the research performed in attempting to analyze one particular stress-measuring instrument called the borehole platened flatjack (bpf). The approach used in this analysis was to combine the analytical solution for the displacements around a borehole and the analytical solution for the bore-hole-platen interaction with the empirical stiffness behavior of the flatjack. The resulting model of the bpf response was then verified using measured laboratory data with very good results. In addition, techniques for applying the method to the field are briefly discussed. The major accomplishments of this comprehensive modeling and testing program are (1) the establishment of the critical installation and site parameters of the hydraulic pressure cell and (2) the development of a systematic procedure for calibrating the cell based on the given values of these critical parameters.

Rock mechanics; Stress analysis; Excavations; Measurement equipment; Boreholes; Analytical instruments

19890101

OP; Conference/Symposia Proceedings

1989

OP 45-91

PRC

Proceedings of the 30th U S Symposium on Rock Mechanics as a Guide for Efficient Utilization of Natural Resources

PA