School of Civil and Environmental Engineering

Ph.D. Thesis Defense Announcement

MULTIPHYSICS STUDY OF CLAYEY SOILS AND SHALES

- IMPLICATIONS TO ENERGY SYSTEMS AND INFRASTRUCTURE -

By Camilo Guerrero

Advisor: Dr. J. Carlos Santamarina (CEE)

Committee Members: Dr. Susan E. Burns (CEE), Dr. J. David Frost (CEE),

Dr. Costas Tsouris (ORNL/CEE), Dr. Hussein Hoteit (KAUST)

Date and Time: June 7, 2024. 8:30 AM EST

Location: Mason 2119. Zoom: https://gatech.zoom.us/j/93843831512

Fluid-mineral interactions and surface-related phenomena play a critical role on the mechanical and flow properties of high specific surface area clayey soils and shales. Multiphysics characterization techniques can assess both the pore fluids and the granular skeleton, in view of energy and infrastructure applications. This thesis explores extreme clayey sediments (Mexico City soils) and natural shales, and places emphasis on nuclear magnetic resonance NMR relaxation and broadband electromagnetic response to investigate free and adsorbed water and gases (hydrogen H2, methane CH4 and carbon dioxide CO2). Gas adsorption tests were conducted using high-pressure and high-temperature low-field NMR. Underlying phenomena include the evolution of water mobility during thixotropic recovery, cementation and its effect on anisotropic swelling, physisorption and selective adsorption. Complementary Grand Canonical Monte Carlo simulations provide atomistic insights into gas adsorption and competitive adsorption. Implications range from subsurface characterization for urban and infrastructure needs, to efficient urban-scale gas storage, and geological storage of carbon and nuclear waste.