1
|
Voigtländer A, Houssais M, Bacik KA, Bourg IC, Burton JC, Daniels KE, Datta SS, Del Gado E, Deshpande NS, Devauchelle O, Ferdowsi B, Glade R, Goehring L, Hewitt IJ, Jerolmack D, Juanes R, Kudrolli A, Lai CY, Li W, Masteller C, Nissanka K, Rubin AM, Stone HA, Suckale J, Vriend NM, Wettlaufer JS, Yang JQ. Soft matter physics of the ground beneath our feet. SOFT MATTER 2024. [PMID: 39012310 DOI: 10.1039/d4sm00391h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
The soft part of the Earth's surface - the ground beneath our feet - constitutes the basis for life and natural resources, yet a general physical understanding of the ground is still lacking. In this critical time of climate change, cross-pollination of scientific approaches is urgently needed to better understand the behavior of our planet's surface. The major topics in current research in this area cross different disciplines, spanning geosciences, and various aspects of engineering, material sciences, physics, chemistry, and biology. Among these, soft matter physics has emerged as a fundamental nexus connecting and underpinning many research questions. This perspective article is a multi-voice effort to bring together different views and approaches, questions and insights, from researchers that work in this emerging area, the soft matter physics of the ground beneath our feet. In particular, we identify four major challenges concerned with the dynamics in and of the ground: (I) modeling from the grain scale, (II) near-criticality, (III) bridging scales, and (IV) life. For each challenge, we present a selection of topics by individual authors, providing specific context, recent advances, and open questions. Through this, we seek to provide an overview of the opportunities for the broad Soft Matter community to contribute to the fundamental understanding of the physics of the ground, strive towards a common language, and encourage new collaborations across the broad spectrum of scientists interested in the matter of the Earth's surface.
Collapse
Affiliation(s)
- Anne Voigtländer
- German Research Centre for Geosciences (GFZ), Geomorphology, Telegrafenberg, 14473 Potsdam, Germany.
- Lawrence Berkeley National Laboratory (LBNL), Energy Geosciences Division, 1 Cyclotron Rd, Berkeley, CA 94720, USA
| | - Morgane Houssais
- Department of Physics, Clark University, 950 Main St, Worcester, MA 01610, USA
| | - Karol A Bacik
- Department of Mathematics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Ian C Bourg
- Civil and Environmental Engineering (CEE) and High Meadows Environmental Institute (HMEI), Princeton University, E208 EQuad, Princeton, NJ 08540, USA
| | - Justin C Burton
- Department of Physics, Emory University, 400 Dowman Dr, Atlanta, GA 30033, USA
| | - Karen E Daniels
- North Carolina State University, 2401 Stinson Dr, Raleigh, NC 27607, USA
| | - Sujit S Datta
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Emanuela Del Gado
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, Washington, DC, USA
| | - Nakul S Deshpande
- North Carolina State University, 2401 Stinson Dr, Raleigh, NC 27607, USA
| | - Olivier Devauchelle
- Institut de Physique du Globe de Paris, Université Paris Cité, 1 rue Jussieu, CNRS, F-75005 Paris, France
| | - Behrooz Ferdowsi
- Department of Civil and Environmental Engineering, jUniversity of Houston, Houston, TX 77204, USA
| | - Rachel Glade
- Earth & Environmental Sciences Department and Mechanical Engineering Department, University of Rochester, 227 Hutchison Hall, P.O. Box 270221, Rochester, NY 14627, USA
| | - Lucas Goehring
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK
| | - Ian J Hewitt
- Mathematical Institute, University of Oxford, Woodstock Road, Oxford OX2 6GG, UK
| | - Douglas Jerolmack
- Department of Earth & Environmental Science, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ruben Juanes
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Arshad Kudrolli
- Department of Physics, Clark University, 950 Main St, Worcester, MA 01610, USA
| | - Ching-Yao Lai
- Department of Geophysics, Stanford University, Stanford, CA 94305, USA
| | - Wei Li
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Stony Brook University, Department of Civil Engineering, Stony Brook, NY 11794, USA
| | - Claire Masteller
- Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Kavinda Nissanka
- Department of Physics, Emory University, 400 Dowman Dr, Atlanta, GA 30033, USA
| | - Allan M Rubin
- Department of Geosciences, Princeton University, Princeton, NJ 08544, USA
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Jenny Suckale
- Computational and Mathematical Engineering, and Environmental Engineering, Stanford University, Stanford, CA 94305, USA
| | - Nathalie M Vriend
- Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO 80309, USA
| | - John S Wettlaufer
- Departments of Earth & Planetary Sciences, Mathematics and Physics, Yale University, New Haven, CT 06520, USA
- Nordic Institute for Theoretical Physics, 106 91, Stockholm, Sweden
| | - Judy Q Yang
- Saint Anthony Falls Laboratory and Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Minneapolis, MN, USA
| |
Collapse
|
2
|
Plummer A, Adkins C, Louf JF, Košmrlj A, Datta SS. Obstructed swelling and fracture of hydrogels. SOFT MATTER 2024; 20:1425-1437. [PMID: 38252539 DOI: 10.1039/d3sm01470c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Obstructions influence the growth and expansion of bodies in a wide range of settings-but isolating and understanding their impact can be difficult in complex environments. Here, we study obstructed growth/expansion in a model system accessible to experiments, simulations, and theory: hydrogels swelling around fixed cylindrical obstacles with varying geometries. When the obstacles are large and widely-spaced, hydrogels swell around them and remain intact. In contrast, our experiments reveal that when the obstacles are narrow and closely-spaced, hydrogels fracture as they swell. We use finite element simulations to map the magnitude and spatial distribution of stresses that build up during swelling at equilibrium in a 2D model, providing a route toward predicting when this phenomenon of self-fracturing is likely to arise. Applying lessons from indentation theory, poroelasticity, and nonlinear continuum mechanics, we also develop a theoretical framework for understanding how the maximum principal tensile and compressive stresses that develop during swelling are controlled by obstacle geometry and material parameters. These results thus help to shed light on the mechanical principles underlying growth/expansion in environments with obstructions.
Collapse
Affiliation(s)
- Abigail Plummer
- Princeton Center for Complex Materials, Princeton University, Princeton, NJ 08540, USA
| | - Caroline Adkins
- Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Jean-François Louf
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
- Department of Chemical Engineering, Auburn University, Auburn, AL 36849, USA
| | - Andrej Košmrlj
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA.
- Princeton Materials Institute, Princeton University, Princeton, NJ 08544, USA
| | - Sujit S Datta
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
| |
Collapse
|
3
|
Kashani A, Cho HJ. The role of poroelastic diffusion in the transient wetting behavior of hydrogels. SOFT MATTER 2024; 20:421-428. [PMID: 38108474 DOI: 10.1039/d3sm01472j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Wetting and water absorption of hydrogels is often encountered in many applications. We seek to understand how wetting behavior can be affected by the time-dependent swelling of hydrogels. We measured the advancing contact angles of water droplets on hydrogels of varying thicknesses where thicker gels absorbed water more slowly. We also observed that, above a threshold advancing speed, water droplets would collapse into a lower contact angle state on the surface. We hypothesized that this collapse threshold speed is a result of competition between the poroelastic diffusion of water into the gel and the advance of the spreading droplet, the thickness of the surface, and the diffusion of water into the gel. Taking the ratio of the diffusion and advancing timescales results in a Peclet number with gel thickness as a characteristic length scale. Our results show that above a Peclet number of around 40, droplets will collapse on the surface across all gel thicknesses, confirming our hypothesis. This work provides simple insight to understand a complex time-dependent wetting phenomenon for a widely used hydrogel.
Collapse
Affiliation(s)
- Amir Kashani
- Department of Mechanical Engineering, University of Nevada, Las Vegas, Las Vegas, NV 89154, USA.
| | - H Jeremy Cho
- Department of Mechanical Engineering, University of Nevada, Las Vegas, Las Vegas, NV 89154, USA.
| |
Collapse
|
4
|
Gao Y, Chai NKK, Garakani N, Datta SS, Cho HJ. Scaling laws to predict humidity-induced swelling and stiffness in hydrogels. SOFT MATTER 2021; 17:9893-9900. [PMID: 34605524 DOI: 10.1039/d1sm01186c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
From pasta to biological tissues to contact lenses, gel and gel-like materials inherently soften as they swell with water. In dry, low-relative-humidity environments, these materials stiffen as they de-swell with water. Here, we use semi-dilute polymer theory to develop a simple power-law relationship between hydrogel elastic modulus and swelling. From this relationship, we predict hydrogel stiffness or swelling at arbitrary relative humidities. Our close predictions of properties of hydrogels across three different polymer mesh families at varying crosslinking densities and relative humidities demonstrate the validity and generality of our understanding. This predictive capability enables more rapid material discovery and selection for hydrogel applications in varying humidity environments.
Collapse
Affiliation(s)
- Yiwei Gao
- Department of Mechanical Engineering, University of Nevada, Las Vegas, Las Vegas, NV 89154, USA.
| | - Nicholas K K Chai
- Department of Mechanical Engineering, University of Nevada, Las Vegas, Las Vegas, NV 89154, USA.
| | - Negin Garakani
- Department of Mechanical Engineering, University of Nevada, Las Vegas, Las Vegas, NV 89154, USA.
| | - Sujit S Datta
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
| | - H Jeremy Cho
- Department of Mechanical Engineering, University of Nevada, Las Vegas, Las Vegas, NV 89154, USA.
| |
Collapse
|
5
|
Carrillo FJ, Bourg IC. Capillary and viscous fracturing during drainage in porous media. Phys Rev E 2021; 103:063106. [PMID: 34271761 DOI: 10.1103/physreve.103.063106] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 05/24/2021] [Indexed: 11/07/2022]
Abstract
Detailed understanding of the couplings between fluid flow and solid deformation in porous media is crucial for the development of novel technologies relating to a wide range of geological and biological processes. A particularly challenging phenomenon that emerges from these couplings is the transition from fluid invasion to fracturing during multiphase flow. Previous studies have shown that this transition is highly sensitive to fluid flow rate, capillarity, and the structural properties of the porous medium. However, a comprehensive characterization of the relevant fluid flow and material failure regimes does not exist. Here, we used our newly developed multiphase Darcy-Brinkman-Biot framework to examine the transition from drainage to material failure during viscously stable multiphase flow in soft porous media in a broad range of flow, wettability, and solid rheology conditions. We demonstrate the existence of three distinct material failure regimes controlled by nondimensional numbers that quantify the balance of viscous, capillary, and structural forces in the porous medium, in agreement with previous experiments and granular simulations. To the best of our knowledge, this study is the first to effectively decouple the effects of viscous and capillary forces on fracturing mechanics. Last, we examine the effects of consolidation or compaction on said dimensional numbers and the system's propensity to fracture.
Collapse
Affiliation(s)
- Francisco J Carrillo
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - Ian C Bourg
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, USA and High Meadows Environmental Institute, Princeton University, Princeton, New Jersey 08544, USA
| |
Collapse
|
6
|
Abstract
Hydrogels are commonly used in research and energy, manufacturing, agriculture, and biomedical applications. These uses typically require hydrogel mechanics and internal water transport, described by the poroelastic diffusion coefficient, to be characterized. Sophisticated indentation-based approaches are typically used for this purpose, but they require expensive instrumentation and are often limited to planar samples. Here, we present Shape Relaxation (SHARE), an alternative way to assess the poroelastic diffusion coefficient of hydrogel particles that is cost-effective, straightforward, and versatile. This approach relies on first indenting a hydrogel particle via swelling within a granular packing, and then monitoring how the indented shape of the hydrogel relaxes after it is removed from the packing. We validate this approach using experiments in packings with varying grain sizes and confining stresses; these yield measurements of the poroelastic diffusion coefficient of polyacrylamide hydrogels that are in good agreement with those previously obtained using indentation approaches. We therefore anticipate that the SHARE approach will find broad use in a range of applications of hydrogels and other swellable soft materials.
Collapse
Affiliation(s)
- Jean-François Louf
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
| | | |
Collapse
|
7
|
Louf JF, Lu NB, O'Connell MG, Cho HJ, Datta SS. Under pressure: Hydrogel swelling in a granular medium. SCIENCE ADVANCES 2021; 7:7/7/eabd2711. [PMID: 33579709 PMCID: PMC7880600 DOI: 10.1126/sciadv.abd2711] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 12/23/2020] [Indexed: 05/28/2023]
Abstract
Hydrogels hold promise in agriculture as reservoirs of water in dry soil, potentially alleviating the burden of irrigation. However, confinement in soil can markedly reduce the ability of hydrogels to absorb water and swell, limiting their widespread adoption. Unfortunately, the underlying reason remains unknown. By directly visualizing the swelling of hydrogels confined in three-dimensional granular media, we demonstrate that the extent of hydrogel swelling is determined by the competition between the force exerted by the hydrogel due to osmotic swelling and the confining force transmitted by the surrounding grains. Furthermore, the medium can itself be restructured by hydrogel swelling, as set by the balance between the osmotic swelling force, the confining force, and intergrain friction. Together, our results provide quantitative principles to predict how hydrogels behave in confinement, potentially improving their use in agriculture as well as informing other applications such as oil recovery, construction, mechanobiology, and filtration.
Collapse
Affiliation(s)
- Jean-François Louf
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Nancy B Lu
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Margaret G O'Connell
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - H Jeremy Cho
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
- Department of Mechanical Engineering, University of Nevada, Las Vegas, NV 89154, USA
| | - Sujit S Datta
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
| |
Collapse
|
8
|
Xiao H, Ivancic RJS, Durian DJ. Strain localization and failure of disordered particle rafts with tunable ductility during tensile deformation. SOFT MATTER 2020; 16:8226-8236. [PMID: 32935714 DOI: 10.1039/d0sm00839g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Quasi-static tensile experiments were performed for a model disordered solid consisting of a two-dimensional raft of polydisperse floating granular particles with capillary attractions. The ductility is tuned by controlling the capillary interaction range, which varies with the particle size. During the tensile tests, after an initial period of elastic deformation, strain localization occurs and leads to the formation of a shear band at which the pillar later fails. In this process, small particles with long-ranged interactions can endure large plastic deformation without forming significant voids, while large particles with short-range interactions fail dramatically by fracturing at small deformation. Particle-level structure was measured, and the strain-localized region was found to have higher structural anisotropy than the bulk. Local interactions between anisotropic sites and particle rearrangements were the main mechanisms driving strain localization and the subsequent failure, and significant differences of such interactions exist between ductile and brittle behaviors.
Collapse
Affiliation(s)
- Hongyi Xiao
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Robert J S Ivancic
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Douglas J Durian
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
9
|
Abstract
Plato envisioned Earth's building blocks as cubes, a shape rarely found in nature. The solar system is littered, however, with distorted polyhedra-shards of rock and ice produced by ubiquitous fragmentation. We apply the theory of convex mosaics to show that the average geometry of natural two-dimensional (2D) fragments, from mud cracks to Earth's tectonic plates, has two attractors: "Platonic" quadrangles and "Voronoi" hexagons. In three dimensions (3D), the Platonic attractor is dominant: Remarkably, the average shape of natural rock fragments is cuboid. When viewed through the lens of convex mosaics, natural fragments are indeed geometric shadows of Plato's forms. Simulations show that generic binary breakup drives all mosaics toward the Platonic attractor, explaining the ubiquity of cuboid averages. Deviations from binary fracture produce more exotic patterns that are genetically linked to the formative stress field. We compute the universal pattern generator establishing this link, for 2D and 3D fragmentation.
Collapse
|
10
|
Armstrong CD, Teixeira AR. Advances in dynamically controlled catalytic reaction engineering. REACT CHEM ENG 2020. [DOI: 10.1039/d0re00330a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dynamically forced input oscillations exhibit ability to surpass classical thermodynamic barriers through reactor operation and surface resonance.
Collapse
|
11
|
Chen SY, Bardall A, Shearer M, Daniels KE. Distinguishing deformation mechanisms in elastocapillary experiments. SOFT MATTER 2019; 15:9426-9436. [PMID: 31737889 DOI: 10.1039/c9sm01756a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Soft materials are known to deform due to a variety of mechanisms, including capillarity, buoyancy, and swelling. In this paper, we present experiments on polyvinylsiloxane gel threads partially-immersed in three liquids with different solubility, wettability, and swellability. Our results demonstrate that deformations due to capillarity, buoyancy, and swelling can be of similar magnitude as such threads come to static equilibrium. To account for all three effects being present in a single system, we derive a model capable of explaining the observed data and use it to determine the force law at the three-phase contact line. The results show that the measured forces are consistent with the expected Young-Dupré equation, and do not require the inclusion of a tangential contact line force.
Collapse
Affiliation(s)
- Shih-Yuan Chen
- Department of Physics, North Carolina State University, NC 27695, USA.
| | - Aaron Bardall
- Department of Mathematics, North Carolina State University, NC 27695, USA
| | - Michael Shearer
- Department of Mathematics, North Carolina State University, NC 27695, USA
| | - Karen E Daniels
- Department of Physics, North Carolina State University, NC 27695, USA.
| |
Collapse
|
12
|
Cho HJ, Datta SS. Scaling Law for Cracking in Shrinkable Granular Packings. PHYSICAL REVIEW LETTERS 2019; 123:158004. [PMID: 31702300 DOI: 10.1103/physrevlett.123.158004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/21/2019] [Indexed: 06/10/2023]
Abstract
Hydrated granular packings often crack into discrete clusters of grains when dried. Despite its ubiquity, an accurate prediction of cracking remains elusive. Here, we elucidate the previously overlooked role of individual grain shrinkage-a feature common to many materials-in determining crack patterning using both experiments and simulations. By extending classical Griffith crack theory, we obtain a scaling law that quantifies how cluster size depends on the interplay between grain shrinkage, stiffness, and size-applicable to a diverse array of shrinkable granular packings.
Collapse
Affiliation(s)
- H Jeremy Cho
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - Sujit S Datta
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, USA
| |
Collapse
|