Acta Mechanica最新文献

{"title":"Modelling of temperature-related phenomena in polymers","authors":"Alexander Lion,&nbsp;Michael Johlitz","doi":"10.1007/s00707-026-04652-2","DOIUrl":"10.1007/s00707-026-04652-2","url":null,"abstract":"<div><p>In comparison with metals, the characteristic temperatures at which polymers change their behaviour are significantly smaller. Temperature-related or temperature-driven phenomena in meltable thermoplastics, weakly crosslinked elastomers or highly crosslinked thermosets have their origin in physical or chemical changes on the microscale. On the macroscopic scale, the mechanical, thermal and caloric properties of polymers change. Some of these phenomena are reversible, others are irreversible. They take place when the temperature is changing due to heat supply from outside or energy dissipation caused by inelasticity and dynamic mechanical loads. As we know, growing temperature increases the mobility of the polymer molecules and changes the rates of chemical reactions. This review article addresses selected phenomena relevant for technical applications. As a reversible phenomenon, the process-dependent stiffening and softening of polymers around the glass transition is treated. Crystallisation, driven by deformation or temperature, is also a reversible phenomenon discussed in this article. Adhesives are applied in everyday life and change their material properties during curing. A phenomenon of high technical importance is ageing. Irreversible chemical ageing increases with the temperature or the environmental oxygen concentration, results from the generation of new crosslinks in combination with chain scission and modifies the mechanical material behaviour. Another characteristic, especially of thermoplastics, is physical ageing. It occurs below the glass transition, corresponds to a decrease in the free volume and leads to an increase in the relaxation times. If polymer parts are dynamically deformed over long times, dissipative heating takes place and leads to an increase in temperature. The focus of this review article is material modelling. Experimental investigations support the argumentation.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 8","pages":"3873 - 3903"},"PeriodicalIF":4.0,"publicationDate":"2026-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00707-026-04652-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Application of the Tanaka non-proportionality parameter for multiaxial fatigue life prediction","authors":"Dariusz Skibicki","doi":"10.1007/s00707-026-04696-4","DOIUrl":"10.1007/s00707-026-04696-4","url":null,"abstract":"<div><p>Non-proportional loading has a significant effect on multiaxial fatigue life. To address this phenomenon, several non-proportionality parameters have been proposed in fatigue research. Analogous parameters are also employed in material plasticity models, such as the Tanaka parameter, though they are based on different principles. To date, however, the Tanaka parameter has not been applied in fatigue life analysis. This study presents a preliminary adaptation of the Tanaka parameter for multiaxial fatigue life prediction models. The approach was evaluated using five fatigue damage parameters: Crossland, Findley, Matake, Papadopoulos, and Papuga–Růžička that do not account for non-proportionality. The evaluation covers five materials, MS1, SM45C, X2CrNiMo17-12-2, Cu-ETP, and S460N, selected for their different sensitivities to non-proportional loading. Incorporating the modified Tanaka parameter substantially reduced prediction errors under out-of-phase and asynchronous loading by 19–77%, achieving accuracy comparable to that obtained under proportional loading conditions. These findings indicate that the proposed approach holds promise for extension to other loading types in future studies.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 8","pages":"3905 - 3924"},"PeriodicalIF":4.0,"publicationDate":"2026-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vibration suppression of multi-span beams with tuned mass dampers under moving loads","authors":"Xijun Huang,&nbsp;Yuyang Chai,&nbsp;Fengming Li","doi":"10.1007/s00707-026-04690-w","DOIUrl":"10.1007/s00707-026-04690-w","url":null,"abstract":"<div><p>The dynamic response analysis and vibration suppression of multi-span beams are more aligned with practical engineering scenarios and entail a greater demand for vibration suppression solutions than those of single-span beams. In this paper, Hamilton’s principle and the assumed mode method (AMM) are employed to establish the equation of motion of the multi-span beam with tuned mass dampers (TMDs) under moving loads. The natural frequencies of the multi-span beams are calculated and show excellent agreement with those obtained from numerical results using finite element analysis. A three-span beam with TMDs is employed as a case study in which parameters such as the TMD mass ratio, frequency, damping ratio, and quantity are comprehensively considered to investigate its vibration suppression effects under moving loads. Meanwhile, the influences of moving load velocity and the number of beam spans on vibration characteristics of the multi-span beam are thoroughly investigated. It is noteworthy that the whale optimization algorithm (WOA) is applied to the vibration suppression of multi-span beams and successfully determines the optimal damper control strategy. The present results are helpful for the dynamic analysis and design of multi-span beams with TMDs under moving loads.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 8","pages":"3821 - 3845"},"PeriodicalIF":4.0,"publicationDate":"2026-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 maxwell-consistent variational framework for piezoelectric laminates: from single plates to multilayer structures","authors":"Ahmet Özkan Özer","doi":"10.1007/s00707-026-04695-5","DOIUrl":"10.1007/s00707-026-04695-5","url":null,"abstract":"<div><p>This paper develops a variational modeling framework for voltage-actuated piezoelectric plates and multilayer laminates under full electromagnetic coupling. By applying Hamilton’s principle to a continuum setting, the formulation retains full electromagnetic coupling through Maxwell’s equations, capturing both electric and magnetic field effects. This enables consistent reductions to quasi-static and electrostatic regimes without sacrificing physical fidelity. Unlike traditional models based on electrostatic assumptions, the present framework accounts for field-induced inertia and magnetic back-reaction forces that can significantly influence system behavior at high frequencies or small scales. From a structural mechanics perspective, the model rigorously couples bending, stretching, and shear deformations with distributed electromagnetic fields. Reduced two-dimensional constitutive laws are derived under Kirchhoff–Love assumptions, yielding a system of partial differential equations that govern laminate dynamics. The framework naturally incorporates both global (surface electrode) and local (patch) actuation scenarios, including correct interface and transmission conditions. Well-posedness in natural energy spaces is established using semigroup theory, supporting future work in control and simulation. Classical plate models are recovered as limiting cases, validating the generality of the approach. The resulting hierarchy of Maxwell-consistent models provides a foundation for accurate modeling and control of smart composite structures with multifunctional capabilities.\u0000</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 8","pages":"3847 - 3872"},"PeriodicalIF":4.0,"publicationDate":"2026-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00707-026-04695-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Analytical and ANN-based approaches for vibration analysis and material optimization of three-phase composite plate","authors":"Dinh Van Dat,&nbsp;Nguyen Van Duy,&nbsp;Tran Quoc Quan,&nbsp;Nguyen Dinh Duc","doi":"10.1007/s00707-026-04672-y","DOIUrl":"10.1007/s00707-026-04672-y","url":null,"abstract":"<div><p>In this paper, the vibration analysis of three-phase composite plate with polymer matrix reinforced with fiber and particle components is investigated. Initially, the effective material properties of the three-phase composite material are derived analytically, considering nonlinear dependencies on the volume fractions of constituent materials and their interactions. Subsequently, the governing equations of motion are formulated using Reddy’s higher-order shear deformation plate theory and solved by applying the Galerkin method combined with the Runge–Kutta method to obtain the vibration characteristics. Further<b>,</b> optimization is performed using the bees algorithm to maximize the natural frequencies with respect to four material variables within specified ranges. Moreover, an artificial neural network (ANN) model is developed and trained on a dataset of 1144 analytical records to efficiently predict the natural frequencies. Finally, numerical results are presented to highlight the influences of reinforcement fibers and particles on the vibration behaviors, showing that increasing the fiber volume fraction leads to higher natural frequencies and lower deflection amplitudes, whereas increasing the particle volume fraction results in reductions in both the natural frequency and the deflection amplitude, thereby providing practical guidelines for manufacturers in selecting suitable material proportions for structural and industrial applications.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 8","pages":"3779 - 3819"},"PeriodicalIF":4.0,"publicationDate":"2026-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlocal elasticity-based analysis of surface-affected piezoelectric nanobeams under thermo-electro-magnetic fields","authors":"R. Selvamani,&nbsp;S. Muthulakshmi,&nbsp;Mawaheb Al-Dossari,&nbsp;N. S. Abd El-Gawaad,&nbsp;Allanazar Qutlimurotov,&nbsp;M. Ijaz Khan","doi":"10.1007/s00707-026-04643-3","DOIUrl":"10.1007/s00707-026-04643-3","url":null,"abstract":"<div><p>This study develops a unified framework to analyze the random vibration, thermo-electro-magnetic response, and mechanical behavior of an elastically restrained piezoelectric nanobeam, incorporating the influence of surface effects under various boundary conditions. The model employs Eringen’s nonlocal elasticity theory together with surface-related factors such as surface stress, surface elasticity, and surface density to capture size-dependent characteristics. The governing equations are derived using Hamilton’s principle. The study further investigates the effects of spring stiffness, nonlocal parameters, applied electric potential, temperature variation, magnetic potential, and moisture concentration. The findings offer useful insights for the design and optimization of nanostructures operating in complex or variable environments.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 8","pages":"3751 - 3777"},"PeriodicalIF":4.0,"publicationDate":"2026-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanically induced dynamic snap-through buckling of thermally shocked circular plates on radially variable nonlinear foundations using a Legendre–Ritz/Wilson-θ computational framework","authors":"Liu Yang,&nbsp;Hsiao-Chun Huang,&nbsp;Ming-Hung Shu","doi":"10.1007/s00707-026-04694-6","DOIUrl":"10.1007/s00707-026-04694-6","url":null,"abstract":"<div><p>In this study, a nonlinear thermomechanical analysis is conducted to explore the dynamic snap-through buckling of circular plates subjected to sudden temperature rises and subsequent impulsive lateral loading. The plate rests on a radially graded nonlinear elastic foundation, modeled as a generalized Winkler-type substrate. The stiffness of this substrate varies with the radius, thereby facilitating precise control over the snap-through response. A closed-form temperature field is first established, followed by the evaluation of the resulting thermal membrane forces and bending moments induced by the rapid heating phase. The transient thermally driven deformation is then computed prior to the application of a mechanical shock load with various spatial distribution functions, which triggers the snap-through instability once the thermal transient stabilizes. Utilizing the Reissner–Mindlin shear deformation theory, the governing dynamic equations are formulated within the framework of axisymmetric kinematics in conjunction with nonlinear strain–displacement relations and uncoupled thermoelasticity. The nonlinear Lagrangian energy functional is formulated, and the dynamic response is obtained through a hybrid numerical–analytical approach that combines a Legendre-polynomial-based Ritz discretization, the Wilson-θ time integration method, and Newton–Raphson linearization for iterative solution of the governing nonlinear system. The snap-through threshold is identified using the Budiansky–Roth criterion, providing refined insights into the instability mechanisms and the role of thermal shock, foundation nonlinearity, and radial stiffness grading on the dynamic stability of thermally loaded structural components.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 7","pages":"3667 - 3682"},"PeriodicalIF":4.0,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148553001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stochastic nonlocal vibrations in fractional thermo-piezoelectric fluid-conveying carbon nanotubes","authors":"Rajendran Selvamani,&nbsp;Thangamuni Prabhakaran,&nbsp;Mawaheb Al-Dossari,&nbsp;N. S. Abd EL-Gawaad,&nbsp;M. Ijaz Khan","doi":"10.1007/s00707-026-04691-9","DOIUrl":"10.1007/s00707-026-04691-9","url":null,"abstract":"<div><p>This paper investigates the stochastic vibration of thermo-piezoelectric fluid-conveying single-walled carbon nanotubes (SWCNTs), incorporating the effects of the Knudsen number and surface characteristics. The Galerkin finite element method, based on nonlocal elasticity theory, is employed to account for variations in the small-scale parameter. Probabilistic characteristics are evaluated using Monte Carlo simulations coupled with the Newmark integration scheme, based on the standard deviation of dynamic displacements. The proposed methodology is validated through comparison with the Eringen-type nonlocal elasticity solution, demonstrating excellent agreement. Furthermore, the effects of load variability and nonlocal parameters on the dynamic behavior of SWCNTs under various boundary conditions are systematically analyzed. Results show that random load disturbances significantly impact the dynamic response, with displacement scattering exceeding predictions based solely on load deviations. The Knudsen number affects complex wave frequencies across both low and high wave numbers, whereas small-scale effects become dominant at higher ranges. Numerical results further illustrate the influence of system parameters on the fluid–structure interaction behavior of the nanotubes.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 7","pages":"3643 - 3666"},"PeriodicalIF":4.0,"publicationDate":"2026-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148552952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical modeling of photothermoelastic moisture plate under multi-temperature theory owing to thermomechanical loading","authors":"Rajneesh Kumar,&nbsp;Nidhi Sharma,&nbsp;Vineeta Rani","doi":"10.1007/s00707-026-04625-5","DOIUrl":"10.1007/s00707-026-04625-5","url":null,"abstract":"<div><p>This study analytically investigates the deformation behavior of an isotropic photothermoelastic moisture plate subjected to coupled thermomechanical loading within the framework of the multi-temperature theory. The governing two-dimensional equations for such a plate are formulated, and suitable potential functions are introduced to enhance analytical tractability and enable partial decoupling of the system. To facilitate solution development, the equations are expressed in a non-dimensional form, after which Laplace and Fourier transform methods are applied to derive the solutions in the transform domain. The model is then analyzed under the influence of a normal force and an external thermal source. The transformed solutions provide a range of field quantities, including displacements, stresses, temperature variation, carrier density distribution, and moisture concentration. Validation of the model is carried out through detailed calculations for a specific material, and numerical results are illustrated graphically to capture the effects of multi-temperature interactions under thermomechanical excitation. The outcomes of this study have promising implications for the design and optimization of semiconductor devices, and other engineering applications where the interplay of thermal, plasma, moisture, and multi-temperature effects is significant.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 8","pages":"3729 - 3750"},"PeriodicalIF":4.0,"publicationDate":"2026-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remarks on distinct electro-magneto-mechanical interfacial imperfections and mass loading sensitivity on BG-type wave propagation in an electro-magneto-elastic fiber-reinforced composite structure","authors":"Abhishek Kumar Singh,&nbsp;Rahul Meher","doi":"10.1007/s00707-026-04671-z","DOIUrl":"10.1007/s00707-026-04671-z","url":null,"abstract":"<div><p>Surface Acoustic Wave (SAW) sensors are increasingly vital in modern technology due to their unique properties, adaptability, and wide applications. This research aims to improve the performance of SAW sensors by increasing mass loading sensitivity and addressing diverse interfacial imperfections. The enhancements aim to significantly improve the efficiency and precision of these sensors. This study examines the dynamic behavior of BG-type waves in piezoelectro-magnetic fiber-reinforced composite (PEMFRC) structures, considering two models: one with an air medium (Model-A) and another influenced by a coated thin film mass loading (Model-B). Central to this investigation is the role of electro-magneto-mechanical interfacial imperfections, categorized into five submodels: mechanically compliant with weak dielectric and magnetic properties (DWMW), high conductivity and permeability (DHMH), low dielectric and magnetic permeability (LDLP), grounded metallic with magnetic grounding (GMMG), and welded interfaces. A micromechanical model of the PEMFRC was developed, deriving effective material constants using advanced composite theory, iso-field approach, the strength of materials, and the rule of mixtures. Tailored boundary conditions for each imperfection enabled the formulation and validation of velocity equations. The study explores four electric-magnetic scenarios: electrically and magnetically short (ESMS), electrically short and magnetically open (ESMO), electrically open and magnetically short (EOMS), and both electrically and magnetically open (EOMO). Graphical analysis highlights electro-magneto-mechanical, electro-mechanical, and magneto-mechanical interactions, emphasizing the influence of mass loading, volume fraction, and imperfections on BG wave phase velocities. The outcomes of this research could revolutionize detection technologies in SAW devices, enhancing their application across diverse sectors such as industry, healthcare, consumer electronics, security, and defence.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"237 7","pages":"3581 - 3614"},"PeriodicalIF":4.0,"publicationDate":"2026-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148553282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}