| Popis: |
There are many applications involving geomaterials where not only the coupling of pore fluid flow and solid skeleton deformation in the bulk porous geomaterial is important, but the additional coupling of fluid flow and deformation in cracks, joints, or interfaces is equally or more important. A short list of examples includes: (1) rock joints with higher permeability than the surrounding rock mass, encountered during large concrete arch dam construction and performance; (2) cracks in rocks generated during oil and natural gas exploration; (3) cracks in rocks generated or encountered during geologic carbon sequestration; (4) base cracks propagated between concrete gravity dams and porous foundation rock; (5) energy concrete pile foundations interfacing soil under thermal cycling and partially saturated conditions; and (6) cracks and fragments in overconsolidated clay soils generated during buried explosive loading. In some of these examples, the interface between dissimilar materials (e.g., concrete and rock, or concrete and soil) make the application of cohesive surface elements particularly meaningful, as opposed to embedded discontinuity formulations [Armero and Callari, 1999] which are deficient in this regard. Previous research has been conducted on determining the proper formulation and finite element implementation of poromechanical cohesive surface elements (CSEs) [Segura and Carol, 2004, Segura and Carol, 2007a] (this list is by no means complete). We extend this approach to what we believe is a more general continuum strong discontinuity formulation, that allows an extension to include thermal effects and partially saturated conditions more seamlessly, when starting with the continuum coupled physics equations (e.g., thermo-poro-mechanics of partially saturated soil or rock). The formulation and finite element implementation are at small strain, and we assume two-dimensional plane strain condition for now, with extension to axisymmetric condition to soon follow. More details can be found in [Sweetser, 2012]. Two numerical examples will demonstrate the CSE implementation. |
