Nevada Nuclear Waste Storage Investigations Project: Analysis of Horizontal Waste Emplacement Boreholes of a Nuclear Waste Repository in Tuff

摘要

In support of the design of a nuclear waste repository in tuff, two dimensional thermal and thermal-mechanical analyses of horizontal emplacement boreholes were performed using finite-element and boundary-element codes. In the finite-element analyses five different equivalent continuum models of a tuff rock mass were used to investigate the state of deformation and stress around the borehole for times up to 300 years following waste emplacement. These models were an isotropic linear elastic model, an ubiquitous joint model with single and orthogonal joints, an a compliant joint model also with single and orthogonal joints. The case of boreholes intersected by discrete fractures was analyzed using boundary-element models. The results of analyses using the various models of the borehole were consistent and indicated stable conditions even when low estimates of the strength of the joints within the tuff rock mass were assumed. 25 refs. (ERA citation 12:036538)