Recently, a workable method was developed for performing overcoring measurements in holes hundreds of meters in length. With the need to obtain in situ stress values for nuclear waste disposal simulation experiments at the Stripa Mine in central Sweden, the task of running both the Power Board's Leeman triaxial cell and hydraulic fracturing in the same hole was undertaken. This paper is a report of the results of the comparative measurements. 9 figures, 1 table.
Rock masses are initially stressed in their current in situ state of stress and to a lesser natural state. Whether one is interested in the extent on the monitoring of stress change. formation of geological structures (folds, faults, The subject of paleostresses is only briefly intrusions, etc. ), the stability of artificial struc discussed. tures (tunnels, caverns, mines, surface excava The last 30 years have seen a major advance our knowledge and understanding of rock tions, etc. ), or the stability of boreholes, a in the in situ or virgin stress field, stress. A large body of data is now available on knowledge of along with other rock mass properties, is the state of stress in the near surface of the needed in order to predict the response of rock Earth's crust (upper 3-4km of the crust). masses to the disturbance associated with those Various theories have been proposed regarding structures. Stress in rock is usually described the origin of in situ stresses and how gravity, within the context of continuum mechanics. It is tectonics, erosion, lateral straining, rock fabric, defined at a point and is represented by a glaciation and deglaciation, topography, curva second-order Cartesian tensor with six compo ture of the Earth and other active geological nents. Because of its definition, rock stress is an features and processes contribute to the current enigmatic and fictitious quantity creating chal in situ stress field.
Coupled Processes Associated with Nuclear Waste Repositories covers the proceedings of the 1985 International Symposium on Coupled Processes Associated with Nuclear Waste Repositories. The study of the behavior of geologic waste repositories is based on the coupled thermal, hydrologic, chemical, and mechanical processes that may occur in these systems. The symposium is sponsored by the U.S. Nuclear Regulatory Commission and the U.S. Department of Energy, in collaboration with the Nuclear Energy Authority in Paris and the Commission of the European Communities in Brussels. This book is organized into five parts encompassing 58 chapters. The introductory parts survey the concerns and interests from American and European agencies that have responsibilities in nuclear waste isolation research. These parts also provide overviews of coupled processes, with a particular emphasis on hydrology, geomechanics, and geochemistry. These topics are followed by summaries of major field projects on nuclear waste repositories in the U.S.A., France, Sweden, Canada, Belgium, and Switzerland. The fourth part covers considerable research results from topical studies of particular coupled processes. The concluding part provides the comments and discussion of various international researchers on the subject. This work will be of value to geology, hydrology, chemistry, thermodynamics, and rock mechanics students and researchers.
