Architecture and management of a geological repository - Andra

4 – Waste disposal PackagesFigure 4.1.5Standard disposal container (illustration for B2.1 packages types)4.1.3.2 Mechanical designUnder normal repository conditions, the mechanical load to be resisted by the standard packagescorresponds to their stacking in the waste disposal cell. A vertical misalignment of 20 mm betweentwo successive packages is also taken into account. This load situation leads to verifying that theconcrete package walls are dimensioned correctly, but generates no requirement for the lid.Static dimensioning calculations have been carried out based on the Eurocode 2 rules [45].. Thedimensioning element for the body is the zone under tensile stress in the vertical walls, given theacceptance of the stacking misalignment. The minimum thickness for the concrete walls (110 mm) isdefined so that the reinforcements may be installed and coated with concrete. Given the choice of ahigh-performance, reinforced concrete with 75 MPa compressive strength for the body, the wallstrength capacity at its minimum thickness is far superior to the forces induced by the loads [41].As indicated above, the behaviour of the waste disposal package should also be assessed in a situationof falling in the cell. It should be verified, therefore, that deformations to the primary waste packagesare sufficiently small to maintain the containment of the radioactive materials and that, in the case ofan eventual loss of containment, this is compatible with the evacuation possibilities through theventilation system.DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM117/495