Modelling of oedometer tests on pellet-powder bentonite mixtures to support mock-up test analysis

EasyChair Preprint 4221, version 2

Abstract

Bentonite mixtures have been recently proposed as a perfect candidate material for sealing deep geological disposals of high-level radioactive waste. In this paper, odometer test has been carried out on a mixture of MX80 bentonite (80% of pellets and 20% of bentonite powder). These mixtures are characterized by a multi-modal pore size distribution, which significantly evolves during the mechanical paths considered in the oedometer tests. The experimental test has been modelled using the finite element Code_Bright the constitutive model used to represent the mechanical response of the mixture is the Barcelona expansive model. A sensitivity analysis is performed to investigate the   effect of the elastic stiffness parameter at micro level for changes in mean effective stress (k_micro) on the global mechanical response of the mixture. Modelling results shows that total porosity decreases inducing the increase of the degree of saturation and the decrease of suction

Keyphrases: Barcelona expansive model, Deep geological disposals, Finite element Code_Bright, Odometer test

@booklet{EasyChair:4221,
  author    = {Arisleidy Mesa Alcantara and Nadia Mokni and Enrique Romero and Sebastia Olivella},
  title     = {Modelling of oedometer tests on pellet-powder bentonite mixtures to support mock-up test analysis},
  howpublished = {EasyChair Preprint 4221},
  year      = {EasyChair, 2020}}