3D modeling of gas pulse test in anisotropic claystones
Selected gas pulse tests on initially saturated claystone samples under isotropic confinement pressure are simulated using a 3D THM code. The constitutive model considers the hydromechanical anisotropy of argillaceous rocks. Cross anisotropic linear elastic law is assumed for the mechanical behaviour. An embedded fracture permeability model is adopted for the hydraulic problem. Permeability and retention curve depend on strains through a fracture aperture. Both hydraulic and mechanical parts are coherently linked trough two bedding angles. Small scale heterogeneity is considered in order to enhance the initiation of flow through preferential paths, following the direction of the bedding planes. HM simulations are carried out considering different bedding orientations, parallel and normal to the imposed flow in the test. Two tests simulation are presented, the first with the sample bedding in vertical position and the second with the bedding horizontal. Simulations are in agreement with recorded upstream and downstream pressures in the test. Flow patterns in each case are compared.
gas flow claystone anisotropy pulse test bedding
D.Arnedo E.Alonso S.Olivella
Department of geotechnical engineering and Geosciences, UPC, Barcelona
国际会议
香港
英文
1-6
2009-05-19（万方平台首次上网日期，不代表论文的发表时间）