{"id":21140,"date":"2026-11-11T13:26:18","date_gmt":"2026-11-11T12:26:18","guid":{"rendered":"https:\/\/navier-lab.fr\/?post_type=event&#038;p=21140"},"modified":"2026-11-11T14:51:13","modified_gmt":"2026-11-11T13:51:13","slug":"navier-seminar-prof-ryan-hurley-johns-hopkins-university-usa","status":"publish","type":"event","link":"https:\/\/navier-lab.fr\/en\/agenda\/navier-seminar-prof-ryan-hurley-johns-hopkins-university-usa\/","title":{"rendered":"Navier Seminar : Prof. Ryan Hurley (Johns Hopkins University, USA)"},"content":{"rendered":"<p><section class=\"kc-elm kc-css-374364 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-550808 kc_col-sm-12 kc_column kc_col-sm-12\"><div class=\"kc-col-container\">\n<div class=\"kc-elm kc-css-483163 kc-title-wrap \">\n\n\t<h1 class=\"kc_title\">Seeing Stress in 4D: X-ray Microscopy of Grains, Rocks, and Heterogeneous Materials<\/h1>\n<\/div>\n<\/div><\/div><\/div><\/div><\/section><section class=\"kc-elm kc-css-990901 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-588460 kc_column kc_col-sm-12\"><div class=\"kc-col-container\"><div class=\"kc-elm kc-css-598083 kc_text_block\"><\/p>\n<h2><strong>Abstract:<\/strong><\/h2>\n<p>How do heterogeneous materials transmit stress, and how does that stress ultimately localize into deformation and failure? In soils, rocks, and many engineered materials, macroscopic behavior emerges from strongly heterogeneous interactions among grains, pores, interfaces, and defects. Yet directly measuring these evolving internal states has historically been difficult.<\/p>\n<p>Over the past two decades, X-ray tomography and diffraction microscopy have created a non-destructive window into the three-dimensional structure and mechanics of materials as they deform. In this talk, I will describe our combined use of these techniques to study deformation mechanisms in granular materials and rocks. We first examine compressed and sheared sands, where grain-resolved measurements reveal heterogeneous force and stress networks, the emergence and statistics of force chains, and the kinetics and kinematics of shear localization. We then turn to sandstone, where diffraction microscopy provides grain-resolved measurements of stress and its evolution toward macroscopic failure, while tomography reveals complementary aspects of microstructure, damage, and material history.<\/p>\n<p>I will conclude by discussing opportunities to extend these approaches across materials classes and time scales\u2014from slow chemo-mechanical evolution at grain boundaries to fracture and dynamic failure\u2014and the potential for laboratory-based 4D X-ray methods to connect mechanics, geoscience, metallurgy, and materials science.<\/p>\n<p>\n<\/div><\/div><\/div><\/div><\/div><\/section><section class=\"kc-elm kc-css-364154 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-704397 kc_column kc_col-sm-12\"><div class=\"kc-col-container\"><div class=\"kc-elm kc-css-422384 kc_text_block\"><\/p>\n<h2><strong>Short bio:<\/strong><\/h2>\n<p>Ryan Hurley is an Associate Professor in the Department of Mechanical Engineering at Johns Hopkins University (JHU) with secondary appointments in Civil and Systems Engineering and Materials Science and Engineering. Ryan serves as a deputy director of the Hopkins Extreme Materials Institute (HEMI) and the Associate Director of the Materials Science in Extreme Environments University Research Alliance sponsored by the Defense Threat Reduction Agency. His research group studies the deformation and failure mechanisms of geomaterials and heterogeneous materials (rocks, granular materials, concrete, metallic lattices) using advanced experimental techniques such as <em>in-situ <\/em>X-ray imaging and diffraction microscopy, constitutive modeling, and micromechanics theory. He received the 2025 JHU Career Impact Award, a 2022 AFOSR YIP Award, a 2021 Army Education Outreach Program Mentor of the Year Award, and a 2020 NSF CAREER Award. He received his Ph.D. in Applied Mechanics from Caltech in 2015 and worked as a postdoctoral researcher at Lawrence Livermore from 2015 \u2013 2017.<\/p>\n<p>\n<\/div><\/div><\/div><\/div><\/div><\/section><\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":186,"featured_media":0,"template":"","class_list":["post-21140","event","type-event","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/event\/21140","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/event"}],"about":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/types\/event"}],"author":[{"embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/users\/186"}],"wp:attachment":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/media?parent=21140"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}