Journal of The Mechanics and Physics of Solids最新文献

{"title":"The deformation mode transition of indented elastic thin shell induced by localized curvature imperfection","authors":"Chongxi Jiao,&nbsp;Xinming Qiu","doi":"10.1016/j.jmps.2025.106039","DOIUrl":"10.1016/j.jmps.2025.106039","url":null,"abstract":"<div><div>Numerous studies have indicated that spherical thin shells exhibit imperfection sensitivity under external pressure or top-indentation, which can greatly impair their loading strength and stability. In this paper, a surprising shift in buckling behavior is achieved for elastic thin shell by locally manipulating the annular imperfection of curvature on a sphere, which reverses the harmfulness wrought by defects. Combined with experiments and simulations, four distinct deformation modes (<em>Near-perfect, Negative, Transitional</em>, and <em>Positive</em>) are detected to exist in the studied parameter space, widely altering the indentation response from notable snap-through to rigid performance without initial bifurcation. Moreover, these diverse characteristics can be successfully captured by a novel theory proposed for solving the axisymmetric behavior of finite curved surface in elasticity. The comprehensive analysis of the intrinsic mechanism of deformation mode transition reveals the significant role of the geometry parameters of imperfections. It turns out that the depth of imperfection is crucial for the mode evolution, while the defect width and curvature radius control the mechanical properties in detail to achieve optimal performance. The design of localized curvature defect gifts the spherical shell with multiple functions that cannot be possessed by itself, including high stiffness and response peak by <em>Positive</em> mode, extremely negative stiffness and post-buckling obstruction by <em>Negative</em> mode, and enhanced energy absorption by <em>Transitional</em> mode. These advantages provide a new possibility for improving the performance of thin shells, and open up a broad prospect for potential applications in the future.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106039"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349237","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":"Synergistic toughening mechanisms of macro- and micro-structures in nacre: Effects of T-stresses","authors":"Yi Yan ,&nbsp;Xi-Qiao Feng","doi":"10.1016/j.jmps.2025.106067","DOIUrl":"10.1016/j.jmps.2025.106067","url":null,"abstract":"<div><div>Through long-term evolution, biological tissues have optimized their components and structures at multiple length scales to meet the requirements of mechanical properties and biological functions. In this study, we explore how the shell macrostructure of nacre and its brick–mortar microstructure are synergistically designed to adapt to external mechanical conditions. We found that the T-stress effect plays a key role in linking the high toughness of nacre with its hierarchical microstructure. When an abalone shell with a convex morphology is subjected to an impact load from a predator, a compressive T-stress arises with the crack initiating in the macroscale nacreous shell. A hierarchical crack bridging model is presented to investigate how the T-stress affects the microscopic stress transfer mechanism and the macroscopic mechanical properties of nacre. It is found that the negative T-stress enhances the interfacial stress of the mineral platelet with waviness, a typical secondary structural feature of the brick–mortar structure. In turn, the amplified interfacial stress further leads to a significant increase in the macroscopic strength and fracture toughness of nacre. This work not only reports a novel toughening mechanism resulting from the structural hierarchy of nacre, but also provides inspirations for the design of biomimetic composite structures with enhanced mechanical properties.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106067"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143294177","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 chemo-thermo-mechanically coupled theory of photo-reacting polymers: Application to modeling photo-degradation with irradiation-driven heat transfer","authors":"Keven Alkhoury ,&nbsp;Shawn A. Chester","doi":"10.1016/j.jmps.2025.106050","DOIUrl":"10.1016/j.jmps.2025.106050","url":null,"abstract":"<div><div>Recent years have seen extensive research on advanced materials, including stimuli-responsive, renewable/degradable, multi-functional materials, and more, offering opportunities for advances in engineering technology. In general, these materials are expected to undergo chemical reactions during their service life. This work formulates a comprehensive thermodynamically consistent, frame-indifferent, photo-chemo-thermo-mechanically coupled theory for photo-reacting polymers undergoing large deformations, with the ability to model irradiation-driven heat transfer. The theory is specialized for photo-degrading polymers subjected to stress while undergoing degradation, and simulations have been used to demonstrate its capabilities.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106050"},"PeriodicalIF":5.0,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143294175","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":"Electromechanical buckling of periodic patterns on stiff film bonded to a compliant substrate – Analytical and numerical postbuckling analyses","authors":"Samy Abu-Salih","doi":"10.1016/j.jmps.2025.106062","DOIUrl":"10.1016/j.jmps.2025.106062","url":null,"abstract":"<div><div>In this work, the analytical and numerical analyses of the electromechanical buckling and postbuckling states of a planar film bonded to a compliant dielectric substrate are presented. The film is a stiff thin metal layer and forms an elastic electrode. The compliant substrate is attached to a bottom fixed and rigid electrode. The film is simultaneously subjected to in-plane compression stresses, which can be induced by the thermal expansion mismatch effect, and to out-plane electrostatic traction that is induced by applying a voltage difference between the upper elastic electrode and the lower fixed electrode. Electromechanical buckling instability stems from the coupling of mechanical buckling instability and electromechanical pull-in instability and instigates mechanical buckling. This manuscript establishes an analytical approach to study the electromechanical critical and post buckling of one-dimensional, square checkerboard, hexagonal, and herringbone periodic buckling modes. Unlike previous works, in the current study the electrostatic traction and energy contributions are derived from the analytical solution of the electric potential function. A modified version of von-Karman plate equations are formulated and used along with the upper-bound energy method to derive analytical solutions for the critical and post electromechanical buckling states. The analytical critical and postbuckling solutions and energy state of periodic patterns are validated by a rigorous numerical finite element solution carried out in COMSOL Multiphysics. It has been found that the buckling stress and periodicity wavelength of a unit cell strongly depend on the applied voltage. The ability to manipulate the value of buckling stress by voltage increases the potential of applications in microsystem technologies such as electrical on/off switching of a surface wrinkling or deformable micromirror.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106062"},"PeriodicalIF":5.0,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143294178","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":"Magnetothermal dehydration induced deformation of hydrogel structures: Modelling and experiment","authors":"Jingda Tang,&nbsp;Huangsan Wei,&nbsp;Wenjie Zhang,&nbsp;Jiayi Lin,&nbsp;Chao Yuan,&nbsp;Tiejun Wang","doi":"10.1016/j.jmps.2025.106061","DOIUrl":"10.1016/j.jmps.2025.106061","url":null,"abstract":"<div><div>Magnetic hydrogels have found broad applications in soft robotics and bioengineering, due to their facile actuation response and good biocompatibility. However, the actuation of magnetic hydrogels embedded with superparamagnetic nanoparticles remains challenging because of the low magnetization. In this work, we investigate the magnetothermal dehydration induced deformation of magnetic hydrogel-elastomer structures through modelling and experiments. The magneto-thermosensitive hydrogel undergoes significant volume change and dehydration under the application of alternating magnetic field. The magnetothermal dehydration of hydrogel is modelled by considering the heat generation of nanoparticles, heat transfer, and volume collapse of thermosensitive hydrogels. These sequential physical processes have not been considered by previous models. The magnetothermal dehydration model can predict the nonlinear temperature change and abrupt volume collapse of magneto-thermosensitive hydrogels during phase transition. Integrating the magnetothermal dehydration with the phase-evolution approach, we obtain the bending solution of magnetic hydrogel-elastomer bilayers. The magnetothermal dehydration induced bending deformation has been realized and predicted in various conditions, including various magnetic particle content, hydrogel thickness and magnetic field intensity. The deformation of complex structures has been further achieved and numerically reproduced by implementing the dehydration strain and modulus change into finite element analysis. This work may provide guidance for the shape morphing and applications of magnetic hydrogels.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106061"},"PeriodicalIF":5.0,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143294179","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":"Normal dynamic adhesion of an infinite elastomer layer on a statistically rough substrate","authors":"ZiJian Chen ,&nbsp;Peng Zhang ,&nbsp;Tao Wang ,&nbsp;XiaoPing Wu ,&nbsp;Zhong Zhang ,&nbsp;Yang Zhao ,&nbsp;Ping Gu","doi":"10.1016/j.jmps.2025.106040","DOIUrl":"10.1016/j.jmps.2025.106040","url":null,"abstract":"<div><div>The dynamic adhesion properties under different pulling speeds on rough substrates have potential value in practical applications. Our primary objective is to ascertain the influence of the pulling speed on the normal stress required for delamination when an infinite elastomer layer delaminates from a statistically random rough rigid substrate. We decouple the interface delamination velocity from the pulling speed based on the deformation of the elastomer during pull-off procedure. Based on the balance of interface stress and elastomer stress, we obtain the varying interface delamination velocity with constant pulling speed. By combining the Greenwood-Williamson statistical model of rough substrate with Muller theory of dynamic adhesion, we obtain a dynamic adhesion model to describe the adhesion force between the elastomer and the rough substrate under various interface delamination velocities, and deduced the pull-off stress <em>σ</em>_pull-off as a power function of the pulling speed <em>v</em>_U, that is <em>σ</em>_pull-off ∝ <span><math><msubsup><mi>v</mi><mi>U</mi><msub><mi>k</mi><mtext>exp</mtext></msub></msubsup></math></span>. The exponential <em>k</em>_exp of the above power function is studied as the pulling speed range of 0.01 ∼ 10 mm/s, the elastomer modulus range of 49.4 ∼ 4000 kPa and the RMS roughness range of 10⁻⁴ ∼ 10⁻⁷ m. Through the experimental verification when the RMS roughness of substrate Z_rough and the modulus of elastomer <em>E</em> satisfy 20×(<em>z</em>_rough/<em>z_k</em>) &lt; (<em>E</em>/<em>E_k</em>)^−0.354 (here <em>z_k</em> = 1 mm, <em>E_k</em> = 1 kPa), the exponential is constant and independent of roughness or modulus. High roughness or high modulus will result in this exponential increase due to the change of the pressing depth probability density function. This finding is expected to simplify the analysis of the dynamic adhesion on the rough substrate and provide ideas for the rough substrate adaptive design of adhesive materials.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106040"},"PeriodicalIF":5.0,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349235","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 theory of fatigue fracture in viscoelastic solids","authors":"Guillaume Lostec ,&nbsp;Julien Caillard ,&nbsp;Davide Colombo ,&nbsp;Rong Long","doi":"10.1016/j.jmps.2025.106047","DOIUrl":"10.1016/j.jmps.2025.106047","url":null,"abstract":"<div><div>Crack propagation in viscoelastic solids under cyclic loading is a fundamental problem underlying the fatigue fracture of elastomers. We present a continuum theory to determine the crack extension per loading cycle for various loading amplitudes, loading frequencies and viscoelastic properties. This is achieved by examining the energy dissipated through viscous effects and the energy available for driving crack growth. In particular, energy dissipation is controlled by an interplay of three time scales: the material relaxation time, the timescale associated with crack propagation (i.e., crack speed) and the loading frequency. By tracking the stress history of material points around the crack tip under concurrent crack propagation and cyclic loading, we derive an integral equation governing crack speed within a loading cycle. Comparisons between numerical solutions of our theory and finite element simulations demonstrate that our theory predicts the influence of material parameters and loading conditions on fatigue fracture at a much lower computational cost.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106047"},"PeriodicalIF":5.0,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143294173","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":"t-PiNet: A thermodynamics-informed hierarchical learning for discovering constitutive relations of geomaterials","authors":"Pin Zhang ,&nbsp;Konstantinos Karapiperis ,&nbsp;Oliver Weeger","doi":"10.1016/j.jmps.2025.106049","DOIUrl":"10.1016/j.jmps.2025.106049","url":null,"abstract":"<div><div>More attention has been paid to integrating existing knowledge with data to understand the complex mechanical behaviour of geomaterials, but it incurs scepticism and criticism on its generalizability and robustness. Moreover, a common mistake in current data-driven modelling frameworks is that history internal state variables and stress are known upfront and taken as inputs, which violates reality, overestimates model accuracy and cannot be applied to modelling experimental data. To bypass these limitations, thermodynamically consistent hierarchical learning (<em>t</em>-PiNet) with iterative computation is tailored for identifying constitutive relations with applications to geomaterials. This hierarchical structure includes a recurrent neural network to identify internal state variables, followed by using a feedforward neural network to predict Helmholtz free energy, which can further derive dissipated energy and stress. The thermodynamic consistency of <em>t</em>-PiNet is comprehensively validated on the synthetic data generated by von Mises and modified Cam-clay models. Subsequently, the potential of <em>t</em>-PiNet in practice is confirmed by applying it to experiments on kaolin clay. The results indicate neural networks embedded by thermodynamics perform better on the loading space beyond the training data compared with the conventional pure neural network-based modelling method. <em>t</em>-PiNet not only offers a way to identify the mechanical behaviour of materials from experiments but also ensures it is further integrated with numerical methods for simulating engineering-scale problems.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106049"},"PeriodicalIF":5.0,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143294174","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 dynamic homogenization method for elastic wave band gap and initial-boundary value problem analysis of piezoelectric composites with elastic and viscoelastic periodic layers","authors":"Mengyuan Gao ,&nbsp;Zhelong He ,&nbsp;Jie Liu ,&nbsp;Chaofeng Lü ,&nbsp;Guannan Wang","doi":"10.1016/j.jmps.2025.106048","DOIUrl":"10.1016/j.jmps.2025.106048","url":null,"abstract":"<div><div>In this paper, we present a dynamic homogenization model for elastic wave propagation analysis in piezoelectric composites with periodic electroelastic and viscoelectroelastic layers. The model is developed using a multiscale homogenization method based on an asymptotic expansion of displacement and electric potential up to the 8th order. By employing the formulation structure of gradient elasticity theory, time-space nonlocal momentum balance equations are derived to predict wave propagation and attenuation in piezoelectric composites more accurately. For verification, we have developed both a plane-wave expansion method and a direct numerical method for comparison, showing that the proposed model is of high accuracy. On this basis, the active control of the band structure in piezoelectric materials is investigated under open and short circuit electric boundary conditions. In addition, the effects of viscoelastic parameters on transient wave propagation and the band gap in a viscoelectroelastic periodic heterogeneous material are analyzed. The developed dynamic homogenization model offers significant computational savings which can be an order higher than the direct numerical solution with an increasing number of microstructures, thus providing an efficient tool for the analysis and design of piezoelectric composite structures under dynamic loading. While we mainly focus on piezoelectric materials in this paper, our model can be readily extended to piezomagnetic materials as summarized in the Appendix.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106048"},"PeriodicalIF":5.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143071668","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 unified morphomechanics theory framework for both Euclidean and non-Euclidean curved crease origami","authors":"Yinzheng Yu,&nbsp;Ruoman Zhu,&nbsp;Kai Wei,&nbsp;Xujing Yang","doi":"10.1016/j.jmps.2025.106046","DOIUrl":"10.1016/j.jmps.2025.106046","url":null,"abstract":"<div><div>Conventional curved crease origami exhibits only Euclidean metrics at the crease, where the surfaces on either side should consistently display convexity on one side and concavity on the other, unfavorably leading to restricted morphologies. Herein, we focus on a special type of origami: non-Euclidean curved crease origami. Additionally, we establish a morphomechanics framework that facilitates the morphology calculation for curved crease origami with arbitrary crease metrics. Specifically, starting with a unified geometric description, it is demonstrated that this non-Euclidean curved crease origami exhibits a broader range of unique morphologies: the convexity and concavity of surfaces can be globally consistent, globally opposite, or vary locally. Additionally, we propose two in-situ reconfiguration strategies: adjusting the folding angle or modifying the sections corresponding to specified angles. Existing calculation methods for designated deployment paths are extended to include non-Euclidean curved crease origami, emphasizing the role of the interfering section in determining deformation limits. Most importantly, we develop a new discrete developable patch model, enabling accurate calculation of the morphology of both Euclidean and non-Euclidean curved crease origami under free deployment paths. Both theoretical and physical models demonstrate the exclusive advantages of complex and diverse morphologies of non-Euclidean curved crease origami, which can be interconverted through two independent reconfiguration strategies. This work broadens the design scope of curved crease origami and provides a systematic framework for subsequent design and theoretical analysis, offering insights for future morphological calculations and active morphology control.</div></div>","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"197 ","pages":"Article 106046"},"PeriodicalIF":5.0,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143071669","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}