The paper presents an application of a simplified 2D model of chemical degradation for a cracked concrete container termed monolith under near surface disposal conditions. The objective is to gain an improved understanding of the rate of degradation of the cracked monolith and its impact on transport of radionuclides under saturated conditions. Chemical degradation of concrete affects physical and mechanical properties and consequently accelerates migration of radionuclides from the cementitious engineered barriers. The abstracted large scale 2D model of chemical concrete degradation is based on a more detailed model who consider Ca leaching from concrete and consequent evolution of the physical properties such as porosity, bulk density, hydraulic conductivity, and tortuosity. Due to the uncertainty associated with the long term evolution of cracks in concrete, different crack networks have been postulated for different periods of time. The paper examines the effect of different crack densities, water boundary condition and magnitude of hydraulic conductivity on the degradation evolution of the monolith and release of radionuclides from conditioned waste grouted in the monolith.
|Title of host publication||1st International Symposium on Cement-Based Materials for Nuclear Wastes|
|Place of Publication||France|
|State||Published - 14 Oct 2011|
|Event||1st International Symposium on Cement-based Materials for Nuclear Wastes - CEA énergie atomique – énergie alternative and SFEN, Avignon|
Duration: 11 Oct 2011 → 13 Oct 2011
|Conference||1st International Symposium on Cement-based Materials for Nuclear Wastes|
|Period||2011-10-11 → 2011-10-13|