THM modelling of Onkalo – final disposal of radioactive spent nuclear fuel

In this paper, an additional modelling work on the backfill material is included. The backfill material refers to granular material used to fill the drift mainly. At present, Friedland clay is considered as one of the candidates. In order to investigate the hydro-mechanical behavior of Friedland clay, a series of laboratory tests are in progress at B+TECH laboratories. Two types of tests have been performed: oedometer tests and infiltration tests. These tests have been simulated using the finite element code Code_Bright using the constitutive model BBM (Alonso et al., 1990).