About

Ryan Hurley is an associate professor in the Department of Mechanical Engineering at Johns Hopkins University, with secondary appointments in the Departments of Civil and Systems Engineering and Materials Science and Engineering. His research group develops and employs novel experiments and numerical models to study the mechanical behavior and failure mechanisms of granular materials, rocks, concrete, and lattice materials. He is a frequent user of synchrotron X-ray facilities worldwide, aiming to observe and understand deformation mechanisms at the smallest length and time scales. Hurley's research has been featured in prestigious journals such as The Journal of the Physics and Mechanics of Solids and The Proceedings of the National Academy of Sciences. He serves as deputy director of the Hopkins Extreme Materials Institute (HEMI) and associate program director of the Materials Science in Extreme Environments University Research Alliance (MSEE URA). He is actively involved in professional societies including the Engineering Mechanics Institute (EMI), the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE), the Society of Engineering Science (SES), and the American Physical Society (APS). Hurley is also a co-editor of the open-source journal Open Geomechanics and has served as a reviewer for numerous journals and funding agencies. He received his PhD from the California Institute of Technology in 2015, where he studied granular materials using computational modeling and small-scale experiments. He completed postdoctoral research at Lawrence Livermore National Laboratory from 2015 to 2017, earning a Department of Energy Secretary’s Appreciation Award for contributions to the Source Physics Experiment. During his time at LLNL, he led a Laboratory Directed Research and Development project on the mechanical compaction of granular materials using X-ray imaging and diffraction. Hurley joined the Whiting School of Engineering faculty in 2018 and has received several awards, including the NSF CAREER award in 2020, the AEOP Mentor of the Year Award in 2021, the AFOSR YIP Award in 2022, and the JHU Catalyst Award in 2023.

Research topics

• Computer Science
• Mechanics
• Geology
• Geometry
• Materials science
• Mathematics
• Composite material
• Condensed matter physics
• Engineering
• Structural engineering
• Optics
• Physics
• Telecommunications
• Data science
• Programming language

Selected publications

• Impact damage across length scales in concrete: Macro-, micro-, and nano-scale damage characterization

  International Journal of Impact Engineering · 2026-04-18

  articleSenior authorCorresponding
  PublisherDOI

• Dataset for article titled "Impact Damage Across Length Scales in Concrete: Macro-, micro-, and nano-scale damage characterization"

  Zenodo (CERN European Organization for Nuclear Research) · 2026-04-19

  datasetOpen accessSenior author

  This repository contains a dataset for the article titled "Impact Damage Across Length Scales in Concrete, Part 1: Macro-, micro-, and nano-scale damage characterization". A Research data description document describes the content of the repository.

  PublisherDOI

• Stress and strain heterogeneity and persistence in uniaxially- and triaxially-loaded sandstone

  2025-11-10

  preprintOpen accessSenior author

  Two critical questions in rock mechanics are whether rocks exhibit localized strains and intra-granular stresses prior to failure, and whether those localized strains and stresses persist until macroscopic failure. Definitive answers have not yet emerged, but would provide insight into rock fracture mechanics as relevant to hydrocarbon extraction and CO2 sequestration. Here, we use X-ray tomography (XRT) and 3D X-ray diffraction (3DXRD) during uniaxial and triaxial tests on Nugget and Bentheimer sandstones to examine strain and stress localization prior to mechanical failure. 3DXRD was used to measure intra-granular lattice strains which were used to compute elastic stress tensors of each grain. Digital volume correlation (DVC) was applied to XRT images to determine the strain field in the sample. Both samples featured marked spatial heterogeneity, localization, and temporal persistence of elevated stresses and strains during their mechanical deformation toward failure. Both samples also featured a majority of grains with at least one principal stress component that was tensile, a feature indicative of their heterogeneous stress transmission. Measurements further revealed that compressive stress orientations and statistics evolved in a similar manner to those of inter-particle forces in loose granular materials, with triaxially-compressed rock exhibiting enhanced grain stress heterogeneity compared to uniaxially-compressed rock. Our results complement recent work by others who employed XRT and scanning 3DXRD to study triaxially-compressed sandstone, but extend those results to uniaxial compression, sandstone of varied porosity, and grain stress measurements throughout the 3D full extent of the samples rather than in a single layer examined with scanning 3DXRD.

  PublisherOA PDFDOI

• Computational Approach for Evaluating the Erosion Rate of Ductile Alloys Impacted by Alumina Particles in Solid Rocket Plumes

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access
  PublisherDOI

• A Mechanism‐Based Constitutive Model for Competent Rocks Subjected to Impact Loading

  Journal of Geophysical Research Solid Earth · 2025-05-01 · 2 citations

  article

  Abstract The dynamic behavior of rocks under dynamic loading conditions is important in a wide range of processes, including meteorite impact, planetary defense, earthquakes, and mining. Phenomenological constitutive models have been extensively developed to capture rock behavior but have difficulty describing response under such extreme conditions. In this study, we present a mechanism‐based model to describe the behavior of rocks under high‐velocity impact and related dynamic loading conditions. The model captures elasticity, the equation of state, micro‐cracking induced fracture, crystal plasticity, granular flow, and porosity evolution of granular material within a thermodynamically consistent finite‐deformation framework. We select sandstone as the model material and determine the material parameters based on independent experimental data. We then conduct high‐velocity ( km/s) impact tests on sandstone samples, and use the experimental data to validate the calibrated model. The results show that our model captures the competition and evolution of the failure mechanisms within sandstone during high velocity impact, and provides good agreement with experiments in terms of in situ impact processes and post‐mortem crater dimensions. Our results also highlight the critical role of the cap component in the granular flow mechanism submodel for capturing the dynamic response of sandstone under high velocity impact, while demonstrating the relative insensitivity to the choice of non‐associative and associative granular flow rules within this particular application. Our model can be applied to other competent rocks (e.g., granite and basalt) and other extreme conditions (e.g., shock and explosion) because of the similarity in deformation and failure mechanisms shared by these geomaterials.

  PublisherDOI

• Advances in Imaging of Granular Matter

  2025-08-27

  book-chapter

  Advances in Imaging of Granular Matter explores the intricate behaviours and interactions of granular materials such as sand. This class of materials exhibit complex patterns and interactions that defy straightforward physical models, which contradicts their apparent simplicity. This chapter emphasises the essential role of advanced imaging techniques in revealing these complexities. Modern imaging modalities, including X-ray radiography and tomography, offer a multidimensional lens, transcending traditional methodological constraints. Integrated with in situ experimentation techniques and sophisticated data analytics, these approaches provide a comprehensive insight into granular materials’ inner workings. Their applications span practical fields, from geotechnical engineering to drug delivery and industrial optimisation. In this chapter, we highlight advanced imaging techniques, enriched with illustrative case studies, to offer an educational guide for graduate students.

  PublisherDOI

• Crystallographic Texture, Structure, and Stress Transmission in Nugget Sandstone Examined With X‐Ray Tomography and Diffraction Microscopy

  Journal of Geophysical Research Solid Earth · 2025-07-01 · 1 citations

  article1st authorCorresponding

  Abstract Subsurface processes in sandstones are controlled by porosity, permeability, and deformation mechanisms, all of which are controlled by a complex interplay of crystallographic rock texture, structure, and micromechanics. Texture, structure, and micromechanics have historically been studied using optical and electron microscopy of thin‐sections. We employed a new combination of in situ X‐ray tomography and ray diffraction microscopy to study crystallographic texture, structure, and grain stresses in 3D. We examined these features in a sample of Nugget sandstone, a sandstone constituting hydrocarbon reservoirs across the American West. Our aims are threefold. First, we demonstrate the utility of X‐ray diffraction microscopy probes for revealing texture, structure, and stress transmission in 3D. Second, we apply these techniques to Nugget sandstone and discuss findings in the context of prior work. Third, we study grain stress tensor evolution during mechanical compression to examine whether their heterogeneity and orientation evolution reflect that of inter‐particle forces in granular materials. Our results show: (a) larger grains featured higher intra‐granular misorientations, possibly from an increased prevalence of cements; (b) pores closed parallel to the loading direction and opened normal to loading; (c) grain stresses featured heterogeneity and orientations similar to inter‐particle forces in non‐cohesive granular materials; (d) grains featured compressive stresses in the loading direction and tensile stresses orthogonal to the loading direction, the latter resisting sample dilation and grain separation. Our work demonstrates the first known application of multi‐modal X‐ray tomography and diffraction microscopy to sandstone, providing new 3D insight into the nature of quartz cement and stress evolution.

  PublisherDOI

• Crystallographic texture, structure, and stress transmission in Nugget sandstone examined with X-ray tomography and diffraction microscopy

  2025-04-22 · 1 citations

  preprintOpen access1st authorCorresponding

  Subsurface processes in sandstones are controlled by porosity, permeability, and deformation mechanisms, all of which are controlled by a complex interplay of crystallographic rock texture, structure, and micromechanics. Texture, structure, and micromechanics have historically been studied using optical and electron microscopy of thin-sections. We employed a new combination of \emph{in-situ} X-ray tomography and ray diffraction microscopy to study crystallographic texture, structure, and grain stresses in 3D. We examined these features in a sample of Nugget sandstone, a sandstone constituting hydrocarbon reservoirs across the American West. Our aims are threefold. First, we demonstrate the utility of X-ray diffraction microscopy probes for revealing texture, structure, and stress transmission in 3D. Second, we apply these techniques to Nugget sandstone and discuss findings in the context of prior work. Third, we study grain stress tensor evolution during mechanical compression to examine whether their heterogeneity and orientation evolution reflect that of inter-particle forces in granular materials. Our results show: (1) larger grains featured higher intra-granular misorientations, possibly from an increased prevalence of cements; (2) pores closed parallel to the loading direction and opened normal to loading; (3) grain stresses featured heterogeneity and orientations similar to inter-particle forces in non-cohesive granular materials; (4) grains featured compressive stresses in the loading direction and tensile stresses orthogonal to the loading direction, the latter resisting sample dilation and grain separation. Our work demonstrates the first known application of multi-modal X-ray tomography and diffraction microscopy to sandstone, providing new 3D insight into the nature of quartz cement and stress evolution.

  PublisherOA PDFDOI

• Quantifying 3D ejecta velocities during high-velocity impact experiments into concrete

  International Journal of Impact Engineering · 2025-09-24 · 3 citations

  articleSenior authorCorresponding
  PublisherDOI

• Grain-scale stress heterogeneity in concrete from in-situ X-ray measurements

  Cement and Concrete Research · 2025-02-08 · 8 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

Recent grants

• Concrete Micromechanics Validated with In-Situ Stress and Strain Measurements

  NSF · $359k · 2021–2024

• CAREER: Quantifying Local Rearrangements and Their Effects in 3D Granular Materials

  NSF · $542k · 2020–2026

Frequent coauthors

• Eric B. Herbold

  Lawrence Livermore National Laboratory

  28 shared

• Chongpu Zhai

  Xi'an Jiaotong University

  21 shared

• Darren C. Pagan

  17 shared

• Stephen A. Hall

  17 shared

• Jonathan P. Wright

  16 shared

• José E. Andrade

  California Institute of Technology

  14 shared

• K.T. Ramesh

  Johns Hopkins University

  14 shared

• Ryan Crum

  Lawrence Livermore National Laboratory

  12 shared

Education

• M.S., Applied Mechanics

  California Institute of Technology

  2012

• B.S., Civil Engineering

  University of Maryland University College

  2011

Awards & honors

• 2020 NSF CAREER Award
• 2021 AEOP Mentor of the Year Award
• 2022 AFOSR YIP Award
• 2023 JHU Catalyst Award
• 2017 Department of Energy Secretary’s Appreciation Award