Arbeitsbericht NAB 13-18

Geomechanical laboratory tests on Opalinus Clay cores from the bore hole Schlattingen SLA-1

Gesteinslabor Dr. Eberhard Jahns was commissioned by NAGRA to execute laboratory tests on drill core material from the bore hole Schlattingen-1.

The objective of the tests was the determination of rock strength and elasticity parameters at different confining levels. Unconfined and confined single stage strength tests had to be carried out for the construction of the Mohr-Coulomb criterion. Petrophysical parameters such as grain density, water potential, and water content were measured for monitoring the condition of the investigated samples. Computed tomography imaging was carried out to estimate the damage caused by the drilling process, transport, storage, and specimen preparation. Moreover, CT imaging was applied to investigate core structure heterogeneities to optimize the sample selection process.