European Journal of Mechanics A-Solids最新文献

{"title":"A stiffness-adjustable low-frequency electromagnetic vibration energy harvesting system with inertial amplifier","authors":"Xiaofang Kang,&nbsp;Hui Wang,&nbsp;Guojun Cai,&nbsp;Shaojie Ma,&nbsp;Hui Li,&nbsp;Ao Zhang,&nbsp;Xinzong Wang,&nbsp;Weidong Liu","doi":"10.1016/j.euromechsol.2026.106431","DOIUrl":"10.1016/j.euromechsol.2026.106431","url":null,"abstract":"<div><div>Traditional energy harvesting devices generally suffer from poor adaptability to low-frequency environments, making it difficult for them to cope with diverse conditions. This paper proposes a stiffness-adjustable electromagnetic induction energy harvesting device comprising four sets of inclined springs connected to adjustable gears, a central vertical spring, and an inertial amplifier mechanism. By altering the rotational angle of the gears, the geometric configuration and parameters of the springs are modified, thereby regulating the system’s dynamic stiffness, natural frequency, and potential energy characteristics and enabling stiffness adjustment for different environmental vibration conditions. The electromechanically coupled dynamical equations are established, and the nonlinear restoring force is approximated using a ninth-order odd-polynomial fitting method. The harmonic balance method is employed to obtain amplitude-frequency response curves. Slowly varying harmonic coefficients are introduced to analyse the stability of periodic solutions. The fourth-order Runge-Kutta method is used to generate maps of RMS load voltage and average output power. Numerical results indicate that the proposed configuration can produce large-amplitude cross-well vibrations over low-frequency and broadband ranges. Coexisting responses and two-dimensional basin sections are computed for bistable, tristable, and quasi-zero-stiffness configurations to examine the dependence of steady-state responses on initial conditions. Finite-duration pulse excitation is used to investigate transitions among coexisting responses. Changing the pulse application time can cause the system to return to its original response, switch between potential wells, or reach a large-amplitude cross-well response. These results provide a theoretical and numerical basis for state regulation in electromagnetic energy harvesters operating under low-frequency excitation.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"122 ","pages":"Article 106431"},"PeriodicalIF":4.7,"publicationDate":"2026-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149200430","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":"Rolling-induced flexural vibration","authors":"Chen Xuan","doi":"10.1016/j.euromechsol.2026.106039","DOIUrl":"10.1016/j.euromechsol.2026.106039","url":null,"abstract":"<div><div>Flexural vibration can be triggered by rolling, an unusual way that has never been studied. Being a planar motion triggered from another motion, it integrates structural dynamics, flexural vibration and contact mechanics. I coin the term “rolling-induced flexural vibration” for this new problem, which is valuable not only to the fundamental theory of structural dynamics but also to various rolling mechanical systems like rolling soft robots. The developed wheels-on-a-string rolling beam that extends the Euler–Bernoulli theory overcomes numerical challenges in contact mechanics by removing inequalities in boundary conditions. An analysis of energy transport and dissipation highlights an unusual rolling beam system. Comparisons are conducted among 3D contact finite element analysis, the rolling beam model and a few analytic solutions. Despite ignoring certain aspect ratio dependence in 3D contact finite elements, the rolling beam model serves as a tool for assessing the efficiency and quality of 3D contact solutions to determine whether switching to alternative contact solvers is necessary. The computational efficiency of the rolling beam model can be up to hundreds of thousands of times higher than that of 3D contact finite elements.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"118 ","pages":"Article 106039"},"PeriodicalIF":4.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146098577","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":"Mechanical behaviour of an optimised novel Ti6Al4V lattice structure fabricated via LPBF: “An experimental and FEA investigation”","authors":"Kirandeep Singh ,&nbsp;Guofang Liang ,&nbsp;Kevin Tetsworth ,&nbsp;Justin Cooper-White ,&nbsp;Deniz U. Erbulut ,&nbsp;Mingxing Zhang","doi":"10.1016/j.euromechsol.2026.106017","DOIUrl":"10.1016/j.euromechsol.2026.106017","url":null,"abstract":"<div><div>Critical-sized bone defects lack the inherent capacity for self-repair and require engineered bone scaffold structures to provide mechanical stability while facilitating osteointegration. Conventional lattice architectures often fail to reconcile high strength with elevated porosity due to discontinuous geometries and stress concentrations at nodal junctions. The Hexanoid (HH) scaffold, inspired by curved surfaces and exhibiting three-dimensional periodicity, has demonstrated superior in-silico cell proliferation but remains mechanically suboptimal. This study introduces a titanium-based Modified Hexanoid (MH) scaffold, engineered to enhance structural performance while retaining porosity conductive to bone ingrowth. Scaffolds were fabricated using Ti6Al4V alloy via Laser Powder Bed Fusion (L-PBF) and mechanically benchmarked against HH, Cubic (CU) and Circular (CR) scaffold structures. Quasi-static compression testing reveals that the MH scaffold achieved an elastic modulus of ∼9 GPa, a yield strength of ∼104 MPa, and a compressive strength of ∼154 MPa, representing improvements of 24 %, 58 %, and 37 %, respectively, over the HH design. The MH design maintained a porosity of approximately 73 %, exceeding HH (∼61 %) and being comparable to CU (∼77 %) and CR (∼76 %). By combining porosity similar to that of trabecular bone with mechanical properties approaching those of cortical bone, the MH scaffold overcomes the strength-porosity trade-off, demonstrating strong potential for load-bearing orthopaedic implants.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 106017"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977413","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":"Accuracy-enhanced modeling of 2024 aluminium alloy in electrically-assisted forming based on direct through-thickness strain measurement","authors":"Kaiyu Zhu ,&nbsp;Hang Yuan ,&nbsp;Xiaojie Hu ,&nbsp;Hongrui Dong ,&nbsp;Xiaoqiang Li ,&nbsp;Bing Pan","doi":"10.1016/j.euromechsol.2025.105996","DOIUrl":"10.1016/j.euromechsol.2025.105996","url":null,"abstract":"<div><div>Electrically-assisted forming enhances the formability of aluminum alloys while maintaining post-forming mechanical properties. However, the multi-physics coupling loading in electrically-assisted forming poses challenges for modeling the anisotropic behavior of aluminum alloy. Conventional associated flow rules typically require complex high-order yield models and customized tooling. In contrast, the non-associated flow rule combined with low-order models has demonstrated comparable accuracy with significantly reduced complexity. Encouraged by its successful application in room-temperature forming, this work proposes integrating the non-associated flow rule with the classical low-order Hill48 yield model and adopting the Grosman hardening model to characterize the anisotropic behavior of 2024-O aluminum alloy under electrically-assisted forming. Both models require accurate determinations of through-thickness strain (<em>ε</em>_<em>zz</em>). Conventional indirect methods often rely on experimentally measured in-plane strain and constant volume assumptions that are unreliable in electrically-assisted forming. To address this challenge, the recently developed mirror-assisted MV-DIC (multi-view digital image correlation) technique was adopted for direct measurement of <em>ε</em>_<em>zz</em> and parameter calibration, which eliminates the reliance on volume conservation assumptions. Electrically-assisted uniaxial tensile tests and anisotropic constitutive modeling were conducted on specimens under five distinct loading conditions. Directly and indirectly measured plastic potential function parameters revealed average relative differences of 6.2 %–14.6 %. The effects of temperature and strain rate on both model parameters and deformation behaviors were also investigated. The experimental and simulation results of shear specimens validated the accuracy of the established model and the superiority of the proposed parameter calibration method.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 105996"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797704","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 thermodynamically consistent and strongly coupled chemo–thermo–hygral framework for early-age concrete","authors":"Jian Ding ,&nbsp;Xin Wang ,&nbsp;Xinyi Ren ,&nbsp;Haim Waisman ,&nbsp;Zhishen Wu","doi":"10.1016/j.euromechsol.2025.105992","DOIUrl":"10.1016/j.euromechsol.2025.105992","url":null,"abstract":"<div><div>Concrete is widely used for its high strength and durability. At early ages, hydration, heat transfer, and moisture transport are the main causes of stress. These processes may lead to nonuniform deformation, high tensile stress, and early cracking, which make prediction difficult. Previous chemo–thermo–hygral models often depended on empirical relations or weak coupling assumptions and lacked thermodynamic consistency. As a result, their theoretical rigor and applicability were limited. In this study, a new free energy density function is proposed within a thermodynamically consistent framework, and a strongly coupled chemo–thermo–hygral model for early-age concrete is developed. The governing equations are derived strictly from thermodynamic principles to describe the spatial and temporal evolution of hydration, temperature, and relative humidity. The model is validated by two-dimensional and three-dimensional simulations and experimental data. The results show that the model can accurately capture the evolution of temperature–humidity coupling and has good predictive ability. A parameter analysis shows that the evolution of relative humidity is sensitive and complex, which highlights its key role in the early-age behavior of concrete. The proposed framework overcomes the limitations of existing models and provides a unified and solid basis for the study of coupled reactive porous media, with important implications for structural design, crack control, and durability improvement.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 105992"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797810","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":"Quasi-static shape control of structures with topologically complex equilibrium sets","authors":"Eszter Fehér ,&nbsp;András Á. Sipos ,&nbsp;Péter L. Várkonyi","doi":"10.1016/j.euromechsol.2025.106000","DOIUrl":"10.1016/j.euromechsol.2025.106000","url":null,"abstract":"<div><div>Inspired by biological systems, we introduce a general framework for quasi-static shape control of load-bearing structures under slowly varying external actions or requirements. In this setting, shape control aims to traverse the stable sub-manifolds of the equilibrium set to meet some predefined requirements or optimization criteria. This paper explores the implications of large shape changes and high compliance, such as the emergence of unstable equilibria and equilibrium sets with non-trivial topology. We identify various adaptivity scenarios, ranging from inverse kinematics to optimization and path planning problems, and discuss the role of time-dependent loads and requirements. The applicability of the proposed concepts is demonstrated through the example of a soft arch that is susceptible to snap-through behavior.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 106000"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884231","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":"Topology optimization of soft robots with local enhancement","authors":"Shikeng Zhao,&nbsp;Jianhua Xiang,&nbsp;Yongfeng Zheng,&nbsp;Jiale Huang","doi":"10.1016/j.euromechsol.2025.106006","DOIUrl":"10.1016/j.euromechsol.2025.106006","url":null,"abstract":"<div><div>The demand for pneumatic soft robots is rapidly increasing for addressing repetitive and complex tasks in engineering. However, traditional soft robots mainly use solid materials without fully considering the material Poisson's ratio's impact on the structural performance. Additionally, local enhanced composites can enhance structural mechanical strength. This study firstly presents the comprehensive study on topology optimization of layered soft robots, using local enhanced composites. An ideal natural pressure field was constructed via fluid loads mathematical model, the density optimization method with penalization and Heaviside filter, were combined to make the structural boundaries clear, and the homogenization method is used to obtain the macroscopic elastic matrices of local enhanced composites. Moreover, design variables of soft robots were updated by using the moving asymptote method, to solve the optimization problem with non-monotonic sensitivity. This paper investigates topology optimization of layered soft robots under various Poisson's ratios, enhanced matrix ratios and enhancement Young's moduli. Computational results indicate that for local enhanced composites, a suitable enhanced matrix ratio can increase soft robots' output displacement, composites with 100 % enhanced matrix ratio have approximately 20 % lower strain energy than those with 0 % ratio.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 106006"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884236","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":"Simple shear in incompressible transversely isotropic hyperelasticity: experiments versus generalized linear models","authors":"Safa Mathlouthi ,&nbsp;Mohamed Trifa ,&nbsp;Makrem Arfaoui ,&nbsp;Luiz Carlos Da Silva Nunes","doi":"10.1016/j.euromechsol.2025.106010","DOIUrl":"10.1016/j.euromechsol.2025.106010","url":null,"abstract":"<div><div>This study presents a comprehensive assessment of five transversely isotropic incompressible hyperelastic models under simple shear loading. The analysis is grounded on two independent experimental datasets involving fiber-reinforced soft materials, enabling a robust evaluation of model performance across a broad range of fiber orientations. Each model was calibrated using shear stress data and subsequently tested on its ability to predict the normal stress response, an indicator of the Poynting effect, without further parameter adjustment. Results show that while all models capture the shear behavior reasonably well, their predictive accuracy for normal stresses varies significantly with fiber alignment and dataset. Notably, one model consistently demonstrated superior performance, maintaining predictive robustness across both datasets. In contrast, other models exhibited greater sensitivity to anisotropy and deformation conditions. The findings underscore the importance of validating constitutive models against multiple stress components to reveal limitations that may be masked in standard calibration procedures. The results of this work gives practical insights into the modeling of fiber-reinforced soft materials and highlights the critical role of multi-criteria validation for selecting reliable hyperelastic formulations in anisotropic elasticity.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 106010"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884229","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":"Oblique impact behavior of bio-inspired turtle shell suture interfaces","authors":"Xu Zhang ,&nbsp;Tom Allen ,&nbsp;Shouji Zhao ,&nbsp;Wu Yan ,&nbsp;Qiang Fu ,&nbsp;Zhenqing Wang","doi":"10.1016/j.euromechsol.2026.106028","DOIUrl":"10.1016/j.euromechsol.2026.106028","url":null,"abstract":"<div><div>The study investigates the dynamic response of bionic suture interfaces inspired by turtle shell under oblique impact at angles of 0°, 15°, 30°, 45°, and 60°. Four geometric configurations (triangular, trapezoidal, anti-trapezoidal, and rectangular) are examined numerically. Results demonstrate that increasing the impact angle enhances frictional energy dissipation through impactor sliding, accompanied by greater energy absorption, structural deformation, and damage area. The interdigitated suture design effectively suppresses interlaminar slippage under oblique loading. When impact occurs perpendicular to the tip angle, the structural response resembles that of a conventional flat plate under normal impact, exhibiting comparatively inferior mechanical performance. Among the tested geometries, the triangular suture interface outperforms others in impact resistance. At identical impact angles, the load-bearing capacities of anti-trapezoidal, trapezoidal, and triangular interfaces exceed that of the rectangular interfaces by 23 %–37 %, 19 %–40 %, and 81 %–89 %, respectively. Notably, the triangular suture with a tip angle of 4.6° demonstrates optimal performance. This systematic study provides valuable data on the oblique impact behavior of bioinspired suture interfaces, offering fundamental guidance for the design of advanced protective composites and bioinspired artificial armor systems.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 106028"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977415","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":"Modelling lateral spread in wire flat rolling","authors":"Mozhdeh Erfanian ,&nbsp;Carl D. Slater ,&nbsp;Edward J. Brambley","doi":"10.1016/j.euromechsol.2026.106027","DOIUrl":"10.1016/j.euromechsol.2026.106027","url":null,"abstract":"<div><div>A mathematical model for wire rolling is developed, focusing on predicting the lateral spread. This provides, for the first time, an analytic model of lateral spread without any fitting parameters. The model is derived directly from the governing equations, assuming a rigid, perfectly plastic material and exploiting the thinness of the wire (in thickness and width) relative to the roller size. Results are compared against experiments performed on stainless steel wire using <span><math><mrow><mn>100</mn><mspace></mspace><mi>mm</mi></mrow></math></span> diameter rolls, demonstrating accurate predictions of lateral spread across a wide range of wire diameters (<span><math><mrow><mn>2</mn><mo>.</mo><mn>96</mn><mspace></mspace><mi>mm</mi></mrow></math></span>–<span><math><mrow><mn>7</mn><mo>.</mo><mn>96</mn><mspace></mspace><mi>mm</mi></mrow></math></span>) and reduction ratios (20%–60%), all without the need for fitting parameters. Since the model requires only seconds to compute, the model’s valid range is explored for varying roll diameter, wire diameter, and reduction ratio, and their effects on the resulting lateral spread characterised. The model can serve as a robust tool for validating FE results, guiding process design, and laying the foundation for future improved models. <span>Matlab</span> code to evaluate the model is provided in the supplementary material.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"117 ","pages":"Article 106027"},"PeriodicalIF":4.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146038059","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}