Part of the Nagra's deep borehole project (TBO) is the determination of mechanical properties of Opalinus Clay. The subject of this tender is the execution and documentation of geomechanical laboratory testing with core material from the TBO boreholes. The aim is to quantify the hydro-mechanical properties of Opalinus Clay at in-situ conditions (recovery depth of approximately 300 to 1 000 m). The 2 main types of tests to be performed are:

— triaxial compression tests, under both drained and undrained conditions,

— high pressure oedometric and unconstrained swelling tests.

Bidding of the 2 test types is organised in 2 separate lots. The bidder is allowed to bid on both lots. A minimum number of tests will be required. Additional tests will be requested depending on timing of core availability and testing performance of the Contractor.

Triaxial testing class-A tests, requiring highly specialised equipment and personnel resources. It is planned to award 3 contracts to 3 bidders, each for a minimum of 30 tests.

Oedometric testing class-A test, (high pressure oedometric tests) and class-B tests (unconstrained swelling), with lower complexity. It is planned to award 2 contracts to 2 bidders, each for a minimum of 20 class-A and 10 class-B tests.