In Situ Determination of Deformation Modulus and Poisson's Ratio of a Rock Mass With Hydraulic Borehole Pressure Cells.
Paper in Rock Mechanics Proc 28th U S Sym on Rock Mechanics Tucson Arizona 6/29-7/1/87 273-81 :9 pages
This paper proposes a new method of in situ determination of deformation modulus and poisson's ratio of a rock mass with hydraulic borehole pressure cells. These two geomechanics constants were determined using a combination of one cylindrical cell and two pre-encapsulated flat cells installed in a single borehole. A variety of states of stress can be generated by induced loading from mining or excavation for long-term tests, and by artificial loading imposed by flatjacks for quick tests. The required instrumentation was simple and inexpensive, and the test procedures were straightforward. The applicability and practicality of the technique was demonstrated by a long-term test conducted in a longwall panel at a coal mine. The investigation revealed the stress dependency of the deformation modulus and the poisson's ratio of this coal.
Paper in Rock Mechanics, Proc. 28th U.S. Sym on Rock Mechanics, Tucson, Arizona, 6/29-7/1/87, 273-81