Journal of The Mechanics and Physics of Solids最新文献

{"title":"Tunable entanglement and strength with engineered staple-like particles: Experiments and discrete element models","authors":"Saeed Pezeshki ,&nbsp;Youhan Sohn ,&nbsp;Vivien Fouquet ,&nbsp;Francois Barthelat","doi":"10.1016/j.jmps.2025.106127","DOIUrl":"10.1016/j.jmps.2025.106127","url":null,"abstract":"<div><div>Entangled matter displays unusual and attractive properties and mechanisms: tensile strength, capabilities for assembly and disassembly, damage tolerance. While some of the attributes and mechanisms share some traits with traditional granular materials, fewer studies have focused on entanglement and strength and there are large gaps in our understanding of the mechanics of these materials. In this report we focus on the tensile properties and mechanics of bundles made of staple-like particles, and particularly on the effect of adjusting the angle between the legs and the crown in individual staples. Our experiments, combined with discrete element models, show competing mechanisms between entanglement strength and geometric engagement between particles, giving rise to an optimum crown-leg angle that maximizes strength. We also show that tensile forces are transmitted by a small fraction of the staples, which is organized in only 1–3 force chains. The formation and breakage of these chains is highly dynamic: as force chains break, they are replaced by fresh ones which were previously mechanically invisible. Entangled matter offers interesting perspectives in terms of materials design which can lead to unusual combination of properties: simultaneous strength and toughness, controlled assembly and disassembly, re-conformability, recyclability.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106127"},"PeriodicalIF":5.0,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143748276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The nonlinear elastic deformation of liquid inclusions embedded in elastomers","authors":"Oluwadara Moronkeji ,&nbsp;Fabio Sozio ,&nbsp;Kamalendu Ghosh ,&nbsp;Amira Meddeb ,&nbsp;Amirhossein Farahani ,&nbsp;Zoubeida Ounaies ,&nbsp;Ioannis Chasiotis ,&nbsp;Oscar Lopez-Pamies","doi":"10.1016/j.jmps.2025.106126","DOIUrl":"10.1016/j.jmps.2025.106126","url":null,"abstract":"<div><div>Elastomers filled with liquid inclusions — as opposed to conventional solid fillers — are a recent trend in the soft matter community because of their unique range of mechanical and physical properties. Such properties stem, in part, from the very large deformations that the underlying liquid inclusions are capable of undergoing. With the objective of advancing the understanding of the mechanics of this emerging class of materials, this paper presents a combined experimental/theoretical study of the nonlinear elastic deformation of initially spherical liquid inclusions embedded in elastomers that are subjected to quasistatic mechanical loads. The focus is on two fundamental problems, both within the limit regime when elasto-capillarity effects are negligible: (<span><math><mi>i</mi></math></span>) the problem of an isolated inclusion and (<span><math><mrow><mi>i</mi><mi>i</mi></mrow></math></span>) that of a pair of closely interacting inclusions. Experimentally, specimens made of a polydimethylsiloxane (PDMS) elastomer filled with either isolated or pairs of initially spherical liquid glycerol inclusions are subjected to uniaxial tension. For the specimens with pairs of inclusions, three orientations of the two inclusions with respect to the direction of the applied macroscopic tensile load are considered, 0°, 45°, and 90°. The liquid glycerol is stained with a fluorescent dye that permits to measure the local deformation of the inclusions <em>in situ</em> via confocal laser scanning fluorescent microscopy. Theoretically, a recently developed framework — wherein the elastomer is considered to be a nonlinear elastic solid, the liquid comprising the inclusions is considered to be a nonlinear elastic fluid, and the interfaces separating the elastomer from the liquid inclusions can feature their own nonlinear elastic behavior (e.g., surface tension) — is utilized to carry out full-field simulations of the experiments. <em>Inter alia</em>, the results show that the deformation of liquid inclusions is significantly non-uniform and strongly influenced by the presence of other liquid inclusions around them. Interestingly, they also show that the large compressive stretches that localize at the poles of the inclusions may result in the development of creases.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106126"},"PeriodicalIF":5.0,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid effects on the fracture toughness of gels","authors":"Prashant K. Purohit,&nbsp;John L. Bassani","doi":"10.1016/j.jmps.2025.106125","DOIUrl":"10.1016/j.jmps.2025.106125","url":null,"abstract":"<div><div>The fracture of polymeric gels has been of growing interest in the last two decades. Well established continuum theories that couple large deformations and fluid diffusion have been applied to gels to determine crack tip fields and the energy release rate. Some studies have combined experiment and calculations to determine the fracture toughness of gels and have shown that fluid effects make a substantial contribution to the toughness. Here we adopt a micro-mechanical view to estimate the fracture toughness of gels, defined as the critical (total) energy release rate, and show how the initiation toughness can be written as a combination of contributions from fiber scission and of fluid–solid demixing at the crack tip. This estimate is based on knowledge of a critical stretch and an associated volumetric strain when fracture is incipient and reveals dependencies on material properties including the solid volume fraction of gels. There have been no known ways to measure the de-mixing contribution directly from experiments, but the results in this paper provide a methodology. We also show how dissipation due to fluid motion as the crack propagates can contribute to the fracture toughness. Detailed results are presented for fibrin gels, which are the main structural component of blood clots.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106125"},"PeriodicalIF":5.0,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Odd elasticity of cylindrical shells and Kirchhoff–Love plates under classic continuum theory","authors":"Zachary Wolfgram,&nbsp;Martin Ostoja-Starzewski","doi":"10.1016/j.jmps.2025.106119","DOIUrl":"10.1016/j.jmps.2025.106119","url":null,"abstract":"<div><div>Odd elastic behavior is investigated in 2d structures with only the odd elastic parameter <span><math><msup><mrow><mi>K</mi></mrow><mrow><mn>0</mn></mrow></msup></math></span> under classic continuum theory. For the Kirchhoff–Love plate with a constant <span><math><msup><mrow><mi>K</mi></mrow><mrow><mn>0</mn></mrow></msup></math></span>, the displacement formulation is independent of the odd parameter, whereas the moment formulation shows dependence. A simply-supported plate under a uniformly distributed load and center point load is investigated using the displacement formulation to determine non-obvious moment fields. A general overview of cylindrical shells with odd elasticity is presented with the approach for the Donnell, Sander, and Flügge models.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106119"},"PeriodicalIF":5.0,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editors’ preface","authors":"","doi":"10.1016/j.jmps.2025.106131","DOIUrl":"https://doi.org/10.1016/j.jmps.2025.106131","url":null,"abstract":"","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"19 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143736559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of the effective polymer network on the extremely large deformation and fracture behaviors of polyacrylamide hydrogels","authors":"Jincheng Lei ,&nbsp;Yuan Gao ,&nbsp;Shuai Xu ,&nbsp;Linchun He ,&nbsp;Zishun Liu","doi":"10.1016/j.jmps.2025.106124","DOIUrl":"10.1016/j.jmps.2025.106124","url":null,"abstract":"<div><div>Current constitutive theories and fracture models face difficulties in capturing the extremely large deformation and fracture behaviors of hydrogels, because the structural and mechanical properties of the effective polymer network dominated in hydrogels are still unknown. In this study, we propose a periodic random network (PRN) method to construct the effective polymer network model of polyacrylamide (PAAm) hydrogel from the bottom up and reveal the effect of the effective polymer network on the extremely large deformation and fracture behaviors of PAAm hydrogels. It is surprising that the PRN models determined by only three parameters capture the extremely large deformation and fracture behaviors of PAAm hydrogel in uniaxial tension experiments very well. The PRN models measure that only about 20 % of monomers and crosslinkers form the effective network in the PAAm hydrogel samples in this work, and the mean monomer number of the effective chains in PAAm hydrogels deviates a lot from that estimated by the ideal network assumption. An anisotropic damage accumulation process of PAAm hydrogel under extremely large deformation before bulk fracture is predicted by PRN models, which has been observed in previous experiments but not explained. This is the fundamental cause that the Lake-Thomas model underestimates the intrinsic fracture toughness of PAAm hydrogels very much. This work provides an insightful method to measure the structural and mechanical properties of hydrogels.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106124"},"PeriodicalIF":5.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grain-size dependence of plastic-brittle transgranular fracture","authors":"Jean-Michel Scherer ,&nbsp;Mythreyi Ramesh ,&nbsp;Blaise Bourdin ,&nbsp;Kaushik Bhattacharya","doi":"10.1016/j.jmps.2025.106116","DOIUrl":"10.1016/j.jmps.2025.106116","url":null,"abstract":"<div><div>The role of grain size in determining fracture toughness in metals is incompletely understood with apparently contradictory experimental observations. We study this grain-size dependence computationally by building a model that combines the phase-field formulation of fracture mechanics with dislocation density-based crystal plasticity. We apply the model to cleavage fracture of body-centered cubic materials in plane strain conditions, and find non-monotonic grain-size dependence of plastic-brittle transgranular fracture. We find two mechanisms at play. The first is the nucleation of failure due to cross-slip in critically located grains within transgranular band of localized deformation, and this follows the classical Hall–Petch law that predicts a higher failure stress for smaller grains. The second is the resistance to the propagation of a mode I crack, where grain boundaries can potentially pin a crack, and this follows an inverse Hall–Petch law with higher toughness for larger grains. The result of the competition between the two mechanisms gives rise to non-monotonic behavior and reconciles the apparently contradictory experimental observations.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106116"},"PeriodicalIF":5.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interlayer Shear Behaviors of Bilayer Graphene with A Moiré Pattern","authors":"Qiancheng Ren ,&nbsp;Jinglan Liu ,&nbsp;Qi Yang ,&nbsp;Pei Zhao","doi":"10.1016/j.jmps.2025.106123","DOIUrl":"10.1016/j.jmps.2025.106123","url":null,"abstract":"<div><div>The mechanical behavior of van der Waals (vdW) interfaces under shear is important for micro-nano mechanics. However, due to the diverse structures of vdW interfaces, there is still a lack of systematic and quantitative research. Here we focus on the simplest vdW interface formed by flat carbon rings, construct twisted bilayer graphene (tBLG) with different moiré patterns through the twist angle design between lattices, and analyze the interfacial behavior under shear from three aspects of experiment, theory, and molecular dynamics simulations. The interfacial shear strength and stiffness for tBLG with different twist angles are obtained, and more results reveal that although the change in twist angle has little effect on the average interlayer distance, the interlayer interaction changed significantly, and with the evolution of the moiré pattern the interlayer damage is still strongly related to the dislocations. This study provides important insights into understanding the interlayer mechanical behavior of vdW interfaces and low-dimensional layered materials.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106123"},"PeriodicalIF":5.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the crack propagation of ductile fibril reinforced polymer membrane with the consideration of drawing fibrils","authors":"Xiangyang Zhou,&nbsp;Diankai Qiu,&nbsp;Zhutian Xu,&nbsp;Linfa Peng","doi":"10.1016/j.jmps.2025.106118","DOIUrl":"10.1016/j.jmps.2025.106118","url":null,"abstract":"<div><div>Microfibril reinforced polymer composites (MFCs) are polymer-polymer composites with ductile fibrils embedded, usually increasing the tenacity of the polymer matrix. One of the successful applications is the expanded polytetrafluoroethylene (ePTFE) reinforced perfluorinated sulfonic acid (PFSA) membrane, in which the embedded ePTFE fibrils evolve into drawing fibril connecting crack surfaces, significantly increasing the fracture toughness of the membrane. Among the fracture modeling techniques, the virtual crack closure technique (VCCT) provides a thermodynamics-consistent explanation of crack propagation of the material, while the effect of drawing fibrils in the case is hard to be considered. The cohesive zone model (CZM) considers the gradual damage progress of the material at the crack tip through the traction-separation law, which is suitable for describing the evolution of drawing fibrils but the applicability of the empirical traction-separation laws to drawing fibrils remains uncertain. This paper establishes the constitutive and fracture models of the ePTFE reinforced PFSA membrane, and numerically realizes the fracture propagation of the microfibril reinforced material through the user subroutine of ABAQUS. For the constitutive modeling, an extended eight-chain model with the consideration of the fibril orientation is established to describe the deformation resistance of the fibril reinforcement. For the fracture modeling, a fracture criterion with the consideration of the negative work of the drawing fibrils at the crack tip is established, and numerically implemented through the extended VCCT. Uniaxial tensile tests and fracture tests of pure and various composite membranes are conducted, which verified the accuracy of the present model in describing the higher mechanical property and fracture tenacity of the composite materials. The model reveals the enhancement mechanism of the ductile fibril network and providing a new perspective of fracture modeling for ductile fibril reinforced polymer membranes.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106118"},"PeriodicalIF":5.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143675642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A nonlinear model of shearable elastic rod from an origami-like microstructure displaying folding and faulting","authors":"M. Paradiso,&nbsp;F. Dal Corso,&nbsp;D. Bigoni","doi":"10.1016/j.jmps.2025.106100","DOIUrl":"10.1016/j.jmps.2025.106100","url":null,"abstract":"<div><div>A new continuous model of <em>shearable</em> rod, subject to large elastic deformation, is derived from nonlinear homogenization of a one-dimensional periodic microstructured chain. As particular cases, the governing equations reduce to the Euler elastica and to the shearable elastica known as ‘Engesser’, that has been scarcely analysed so far. The microstructure that is homogenized is made up of elastic hinges and four-bar linkages, which may be realized in practice using origami joints. The equivalent continuous rod is governed by a Differential–Algebraic system of nonlinear Equations (DAE), containing an internal length ratio, and showing a surprisingly rich mechanical landscape, which involves a twin sequence of bifurcation loads, separated by a ‘transition’ mode. The latter occurs, for simply supported and cantilever rods in a ‘bookshelf-like’ mode and in a mode involving faulting (formation of a step in displacement), respectively. The postcritical response of the simply supported rod exhibits the emergence of folding, an infinite curvature occurring at a point of the rod axis, developing into a curvature jump at increasing load. Faulting and folding, excluded for both Euler and Reissner models and so far unknown in the rod theory, represent ‘signatures’ revealing the origami design of the microstructure. These two features are shown to be associated with bifurcations and, in particular folding, with a secondary bifurcation of the corresponding discrete chain when the number of elements is odd. Beside the intrinsic theoretical relevance to the field of structural mechanics, our results can be applied to various technological contexts involving highly compliant mechanisms, such as the achievement of objective trajectories with soft robot arms through folding and localized displacement of origami-inspired or multi-material mechanisms.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"200 ","pages":"Article 106100"},"PeriodicalIF":5.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143675592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}