(GRS 161) The DEBORA-Project: Development of Borehole Seals for High-Level Radioactive Waste – Phase II

During the phase I (1991 - 1995) of the DEBORA ("Development of Borehole Seals for High-Level Radioactive Waste") project a theoretical desk study was performed to identify the requirements for and the tasks of high-level waste (HLW) borehole seals.
Crushed salt was identified as the most suitable sealing material. According to model calculations the crushed salt in the HLW disposal boreholes reaches the properties of the surrounding undisturbed rock mass by convergence induced compaction within very few years (< 10 years). This report describes experimental and theoretical work performed within phase II of the project to confirm and further improve the material models used to predict the compaction behaviour of crushed rock salt in long-term safety analyses.