Position: PhD in Geomechanics
Director: Antonio Gens
Related grant: Grants for pre-doctoral contracts for the training of doctors 2020
Research line: The storage of nuclear waste within geological formations is a current and responsible option in many countries that use nuclear-electric energy, for the long-term confinement of spent nuclear fuel. In a deposit of radioactive waste housed in a clay formation, hydrogen and other gases can be generated due to corrosion of metallic materials under anoxic conditions, radioactive decay of waste, and radiolysis of water. If the rate of gas production exceeds the rate of gas diffusion within the pores of the clay, a discrete gas phase will form and accumulate until its pressure is large enough to exceed the inlet pressure of the material environment, at which point a dilating and advective gas flow is expected to occur.
The purpose of this research proposal is to better represent numerically the processes that govern advective gas movement both in low permeability clay rocks and engineering barriers based on clay materials. In this work, special attention will be paid to the mechanisms that control the opening, flow, and closure of fractures / cracks (flow paths/paths) that occur locally in the clay, and their impact on the performance of the designed clay barrier, both on a particular/local scale and on a general scale of the construction solution.