Theoretical and Experimental Solutions for Dynamic-Hydraulic-Mechanical Processes in Geoenvironmental Engineering

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Efficient and sustainable solutions to global geoenvironmental challenges (e.g. water supply, energy generation, and geotechnical infrastructure sustainability) require a fundamental understanding of particle transport in porous media. The precipitation and entrapment of solid particles in porous media are crucial phenomena, resulting in pore blockage during the operation of geothermal, hydrocarbon, and aquifer storage and recovery (ASR) systems; impacting water quality and system competence. Conversely, cementation and pore-filling could have a positive effect on engineering properties of geomaterials; and are key mechanisms behind bio-mediated stabilization of infrastructure. The advanced understanding of physical interactions between mechanical waves and entrapped fine particles in porous media is critical for developing groundbreaking stimulation strategies to: (i) avoid/reduce/treat pore blockage; and (ii) control pore blockage to enhance field-scale bio-mediated soil stabilization. There are many uncertainties regarding fundamental mechanisms involved in particle transport, and wave propagation in saturated media. Furthermore, experimental attempts to establish the link between the aforementioned two phenomena have yielded inconsistent results; and there is currently no coupled theory to explain wave propagation in saturated media containing entrapped fines. The underlying theme of the proposed research program relates to dynamic-hydraulic-mechanical coupling in porous media, and focused on substantially closing these critical scientific gaps. We propose rigorous theoretical modeling and advanced physical experimentation, to achieve three specific goals: 1) develop new microscale theoretical models to enable accurate study of precipitation/mobilization/straining of fine particles. 2) Develop new multiscale theoretical models for wave propagation in saturated media, exploring coupled relations between wave parameters, the microstructure, and the macroscale parameters of the domain. Finally, from the new fundamental understandings, we will develop new theory to explain for the first-time physical interactions between mechanical waves and entrapped fines. 3) Conduct pilot-scale lab tests to verify the developed models, and to evaluate wave effects on formation and rupture of physical/biological clogging. Hence, this research program will add a new dimension to design of energy, water and bio-stabilization processes by integrating vibratory stimulation into injection strategies. The theoretical and experimental models obtained from this research will not only advance the scientific knowledge, but the state of practice in various geoenvironmental operations. The obtained solutions could prevent environmental disasters due to wellbore breakout and contamination of soil and water resources. Developed strategies will also enable large-scale implementation of bio-mediated stabilization techniques, which have been prevented mainly due to clogging.