Abstract

Fracture propagation in ice shelves and glaciers in Greenland and Antarctic can cause the detachment of icebergs and accelerate ice flow by enhancing basal sliding, contributing to global sea level rise; this increases the risk of coastal flooding and makes storm surges more damaging, threatening coastal cities and infrastructure. For example, Saudi Arabia's Ras Tanura and Yanbu ports are highly vulnerable to rising sea levels, with a 1-meter rise predicted by 2070 or sooner, posing a critical threat to their operation. It has been hypothesized that such rapid sea level rise is plausible due to hydraulic fracture of glaciers and ice shelves triggering runaway ice loss due to marine ice cliff and marine ice sheet instabilities. Therefore, it is important that we improve our understanding of the fracture mechanics of ice shelves and glaciers and better represent their dynamics in ice sheet and earth system models. In this presentation, I will provide an overview of our recent work on modeling hydraulic fracture using damage mechanics approaches. First, I will describe a poro-damage phase-field and cohesive fracture approaches for modeling the quasi-static propagation of water-filled crevasses, which ignores fluid flow and thermal effects. Second, I will discuss a two-scale cohesive fracture approach that incorporates turbulent fluid flow and accounts for melting/refreezing in fractures to explore the conditions enabling rapid supraglacial lake drainage events. Third, I will present a combined inverse and forward modeling approach for assessing and evolving damage in shallow ice shelves and its application to rift propagation in Larsen C ice shelf. I will end with some remarks on the development and use of adaptive finite element methods, parallel computing, and machine learning surrogates models, which is crucial for understanding geophysical fracture processes over large scale domains and decadal to century timescales, assessing the risk of natural hazards, and energy harvesting from enhanced geothermal systems.

 Acknowledgements: This work is funded through grants from the US National Science Foundation and National Aeronautics and Space Administration.  

Biography

Ravindra Duddu got his B. Tech in Civil Engineering from the Indian Institute of Technology Madras and his Ph.D. in Civil and Environmental Engineering from Northwestern University. Subsequently, he held postdoc appointments at the University of Texas at Austin and Columbia University in the City of New York. Currently, he is an Associate Professor at Vanderbilt University. His research interests are in computational solid mechanics with a focus on multi-physics modeling of material damage evolution. He has advanced the use of continuum damage mechanics models for simulating fracture processes in glacier ice and rock materials. He is a recipient of the US NSF early CAREER award, USIEF Fulbright Kalam-Climate Fellowship, UK The Royal Society International Exchanges Schemes award, and ONR Summer Faculty Fellowship. He is a member of American Society of Civil Engineers (ASCE), American Geophysical Union, United States Association for Computational Mechanics, and American Society of Mechanical Engineers (ASME). He is the Chair of technical committees on Computational Mechanics and Fracture and Failure Mechanics associated with ASCE and ASME.