ABSTRACT
Within the scope of works to provide the necessary rock mechanics support for the site investigations has the Swedish Nuclear Fuel and Waste Management Co. (SKB) studied some of the available equipment’s for in-situ stress measurements. One part of this work was to investigate the variability of the hydraulic fracturing technique. This was done by clustering measurement sections close to each other at depths where the geology is similar and homogenous. Rock stress measurements by overcoring have also been done in the holes measured by hydraulic fracturing. The overcoring results are compared to the ones from the hydraulic fracturing and some conclusions regarding the different results are made. The boreholes in which the measurements have been made are quite well characterized which allows a good possibility to correlate the measured results to the geology in the measured sections.
