Acta Mechanica最新文献_第3页

Equilibria and stability of a rigid body suspended by a flexible string: analyzing two suspension systems 柔弦悬吊刚体的平衡与稳定性：分析两种悬吊系统

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-12 DOI: 10.1007/s00707-025-04397-4

Jens Wittenburg, Attila Genda

{"title":"Equilibria and stability of a rigid body suspended by a flexible string: analyzing two suspension systems","authors":"Jens Wittenburg, Attila Genda","doi":"10.1007/s00707-025-04397-4","DOIUrl":"10.1007/s00707-025-04397-4","url":null,"abstract":"<div><p>Subject of investigation are equilibrium positions and their stability of a rigid body suspended by a massless, flexible, inextensible string of given length, the endpoints of which are attached to two points of the body. Two suspensions are investigated. In Suspension I, the string is passed over two frictionless hooks fixed on a horizontal line a given distance apart. In Suspension II, the string is passed over a frictionless pulley of given radius, the center of which is a fixed point. The center of mass is an arbitrarily given point of the body. Suspension I: Equilibrium positions for a given center of mass are determined by the positive roots of two 8<sup>th</sup>-order polynomial equations. A bifurcation curve divides a body-fixed plane into domains differing in the number of equilibrium positions depending on the location of the center of mass. The total number of equilibrium positions is between four and eight, depending on the parameters of the system. Stability and instability criteria are formulated. By the results obtained, the special case of the single-hook suspension is covered. Suspension II: Every mathematical relationship describing suspension I is valid, in modified and more complex form, for suspension II.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 8","pages":"4445 - 4459"},"PeriodicalIF":2.9,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00707-025-04397-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143475","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}

引用次数: 0

Notch effect on potential fracture behaviours of a cracked solid under mixed Mode-I/II loading 缺口对i /II型混合加载下裂纹固体潜在断裂行为的影响

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-12 DOI: 10.1007/s00707-025-04384-9

Lu Wang, Yu-jun Xie

{"title":"Notch effect on potential fracture behaviours of a cracked solid under mixed Mode-I/II loading","authors":"Lu Wang, Yu-jun Xie","doi":"10.1007/s00707-025-04384-9","DOIUrl":"10.1007/s00707-025-04384-9","url":null,"abstract":"<div><p>Based on the energy-based fracture modelling for multiple-crack initiation, present work quantitatively explains how a blunted crack tip affects the fracture behaviours. If a crack tip is blunted, the original crack becomes a notch. When a notch under mixed Mode-I/II loading is narrow enough, the asymptotic singular stress fields are approximately true, which implies that the six energy-based driving forces distributed along the boundary of a notch tip still exist. These energy-based driving forces will drive the notch tip to fracture, including the notch kinking and branching. As the crack tip is blunted, the sifting constraints between the sub-boundaries of original crack tip are weakened. Therefore, the potential fracture configurations for an original ideal crack tip will change. The notch effect mainly cover that all energy-based driving forces parallel to the crack surface have the potential to trigger the crack tip to fracture, synthesis and decomposition of the adjacent energy-based driving forces, and the fracture toughness for notch branching and extension increases after a crack-tip blunting. Two application examples of present fracture modelling have been carried out. The predicted fracture behaviours are consistent with the fracture behaviour in the experiments, which should refresh the understanding on the notch tip kinking and branching for the notched solids under mixed Mode-I/II loading.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 8","pages":"4417 - 4443"},"PeriodicalIF":2.9,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143476","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}

引用次数: 0

A fractional-order constitutive model for nonlocal piezoelectricity 非局部压电的分数阶本构模型

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-11 DOI: 10.1007/s00707-025-04387-6

Shubham Desai, Sai Sidhardh

引用次数: 0

Machine learning-assisted topology optimization framework for designing 2D structures based on micropolar elasticity 基于微极性弹性的机器学习辅助二维结构拓扑优化框架

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-11 DOI: 10.1007/s00707-025-04380-z

H. W. Zhou, M. Shaat, X.-L. Gao

{"title":"Machine learning-assisted topology optimization framework for designing 2D structures based on micropolar elasticity","authors":"H. W. Zhou, M. Shaat, X.-L. Gao","doi":"10.1007/s00707-025-04380-z","DOIUrl":"10.1007/s00707-025-04380-z","url":null,"abstract":"<div><p>A machine learning-assisted topology optimization framework for designing 2D structures is developed. A micropolar elasticity-based finite element model is formulated and integrated into this framework to compute the material compliance, which accounts for microstructure effects. The topology optimization (TO) procedure is based on the modified SIMP method and begins with generating three intermediate material layouts with distinct density profiles. These layouts serve as inputs for a machine learning (ML) model trained to predict the final optimal layout for given material properties and prescribed loading and boundary conditions. Three ML models—feedforward neural networks (FFNN), convolutional neural networks (CNN), and generative adversarial networks (GAN)—are trained and implemented to execute the ML-assisted TO framework. Numerical results reveal that the microstructure effects, as represented by the two micropolar material constants, can significantly influence the optimal topology and structural stiffness. Compared to the traditional TO approach, the newly developed ML-assisted TO framework effectively reduces computation time and lowers computational energy consumption. The new ML-assisted TO framework provides an accurate, efficient, and computationally viable tool for structural and material designs.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 8","pages":"4357 - 4385"},"PeriodicalIF":2.9,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00707-025-04380-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143294","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}

引用次数: 0

Exponential stability of a thermoelastic nonlinear shear beam 热弹性非线性剪切梁的指数稳定性

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-09 DOI: 10.1007/s00707-025-04390-x

My Driss Aouragh, Mustapha El Baz, Abdelaziz Soufyane

{"title":"Exponential stability of a thermoelastic nonlinear shear beam","authors":"My Driss Aouragh, Mustapha El Baz, Abdelaziz Soufyane","doi":"10.1007/s00707-025-04390-x","DOIUrl":"10.1007/s00707-025-04390-x","url":null,"abstract":"<div><p>In this paper, we study the stabilization of a thermoelastic nonlinear shear beam model. We incorporate thermal dissipation into the transverse displacement equation, following Fourier theory. The Shear beam model constitutes an improvement over the Euler-Bernoulli beam model by adding the shear distortion effect but without rotary inertia. Unlike Euler-Bernoulli and Rayleigh beam models, the Shear model has two dependent variables for dynamic of the beam. First, by using the Faedo-Galerkin method, we prove the well-posedness of the system. Second, by using the integral-type multiplier method, we prove that the energy of the system decays exponentially regardless of any relationship between coefficients of the system, since the system has only one wave speed. Numerically, by using a finite element scheme in space and both implicit Euler and Crank-Nicolson methods in time, we prove that the associated discrete energy decays. Then, we present a priori error estimates from which the linear convergence of the algorithm is derived under suitable regularity conditions. Finally, we present some numerical experiments, to support our theoretical results.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 8","pages":"4329 - 4355"},"PeriodicalIF":2.9,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143269","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}

引用次数: 0

Parameter estimation in cyclic plastic loading 循环塑性加载中的参数估计

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-09 DOI: 10.1007/s00707-025-04385-8

Martin Kovanda, René Marek, Petr Tichavský

{"title":"Parameter estimation in cyclic plastic loading","authors":"Martin Kovanda, René Marek, Petr Tichavský","doi":"10.1007/s00707-025-04385-8","DOIUrl":"10.1007/s00707-025-04385-8","url":null,"abstract":"<div><p>The increasing complexity of modern constitutive models of cyclic metal plasticity requires more efficient ways to achieve their optimal calibration. Traditional approaches, such as random search combined with Nelder–Mead optimization, are computationally expensive. In addition, they struggle with highly non-convex functions that have numerous local minima and complex behavior, making these methods highly sensitive to initial conditions. While numerical refinement is key, a better prediction for its initial point directly saves costs. In this work, we focus only on the uniaxial cyclic loading, as it is the dominant part of a general calibration process for such a model and can also utilize a closed-form solution, further speeding up the procedure. We propose a neural network framework with a loss function that combines the loss on both the predicted parameters and the generated stress responses. This network is then used to predict an initial point for Nelder–Mead optimization. Our method was also compared to the non-gradient Tensor Train Optimization method on both synthetic data and measured experiments.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 8","pages":"4311 - 4328"},"PeriodicalIF":2.9,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00707-025-04385-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143271","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}

引用次数: 0

Flexural response of bidirectional FG-plates via hyperbolic integral higher order shear deformation theory 基于双曲积分高阶剪切变形理论的双向fg板弯曲响应

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-09 DOI: 10.1007/s00707-025-04373-y

Touam Lakhemissi, Billel Rebai, Abdelhakim Bouhadra, Belgacem Mamen, Abderrahmane Menasria, Fouad Bourada, Abdelouahed Tounsi, Rawda A. Idrees, Saad Althobaiti, Mahmoud M. Selim

{"title":"Flexural response of bidirectional FG-plates via hyperbolic integral higher order shear deformation theory","authors":"Touam Lakhemissi, Billel Rebai, Abdelhakim Bouhadra, Belgacem Mamen, Abderrahmane Menasria, Fouad Bourada, Abdelouahed Tounsi, Rawda A. Idrees, Saad Althobaiti, Mahmoud M. Selim","doi":"10.1007/s00707-025-04373-y","DOIUrl":"10.1007/s00707-025-04373-y","url":null,"abstract":"<div><p>The current work aims to study the mechanical-elastic bending of bidirectional functionally graded materials using a combined integral theory (I-HSDT) with the transverse shear effect. The presented model contains undetermined integral in which reduce the numbers of the unknown’s variables and therefore reduce the calculation time while ensuring the accuracy of results. This combined-integral model satisfies the free surface conditions by using the exponential-hyperbolic warping function. Unlike the two-materials unidirectional FG plate. The studied bidirectional functionally graded plate is made of three constituents (Al<sub>2</sub>O<sub>3</sub>–ZrO<sub>3</sub>–Al) with a different power law volume fraction. The variations of the volume fractions are continuously varied in two perpendicular direction (longitudinal and thickness direction). The analytical solution of the mechanical bending analysis is determined by the virtual work principle and resolved via Navier's approach functions. The validity and the exactness of the current combined integral theory are confirmed by the comparisons study with the others similar model found in the open literature. Also, various parametric studies are presented and discussed to illustrates the impact of the composition of 2D-FGM, thickness, width-to-length ratio on the flexural characteristics of the simply supported FG plate. </p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 8","pages":"4295 - 4309"},"PeriodicalIF":2.9,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143268","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}

引用次数: 0

An Updated Lagrangian framework for large deformation analysis of thin elastomeric materials 薄型弹性材料大变形分析的拉格朗日框架

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-08 DOI: 10.1007/s00707-025-04363-0

Nasser Firouzi, Francesco Tornabene, Ji Wang, Wojciech Macek, Przemysław Podulka

{"title":"An Updated Lagrangian framework for large deformation analysis of thin elastomeric materials","authors":"Nasser Firouzi, Francesco Tornabene, Ji Wang, Wojciech Macek, Przemysław Podulka","doi":"10.1007/s00707-025-04363-0","DOIUrl":"10.1007/s00707-025-04363-0","url":null,"abstract":"<div><p>Elastomeric materials are widely used in several engineering disciplines. Due to importance of these materials in vast variety of industries, in this paper, a nonlinear finite element formula for large deformation analysis of hyperelastic elastomeric materials is developed. Both Total Lagrangian (TL) and Updated Lagrangian (UL) frameworks are adopted for developing the FE relations. Firstly, the Total Lagrangian formulation is derived, and then, the Updated Lagrangian framework is achieved after some manipulations the TL relations. This method is derived for the first time which bridges Total Lagrangian framework to the Updated Lagrangian framework. The formulation accounts for isotropic as well as anisotropic hyperelastic materials. Moreover, both compressible and incompressible cases are considered. Eventually, diverse applications of FEM in analyzing large deformation hyperelasticity across various engineering domains are explored. The various approaches and applications showcase the extensive capabilities of both Total and Updated Lagrangian frameworks in this domain.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 8","pages":"4277 - 4294"},"PeriodicalIF":2.9,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142765","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}

引用次数: 0

Dynamics of planar elasto-plastic Timoshenko-type beams at finite strains 有限应变下平面弹塑性timoshenko型梁的动力学

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-07 DOI: 10.1007/s00707-025-04382-x

Tien Long Nguyen, Carlo Sansour, Mohammed Hjiaj, Pisey Keo

引用次数: 0

Graphene origami-reinforced cylindrical shells: free vibration analysis for enhanced structural performance 石墨烯折纸增强圆柱壳：增强结构性能的自由振动分析

IF 2.9 3区工程技术

Acta Mechanica Pub Date : 2025-06-07 DOI: 10.1007/s00707-025-04374-x

Zaid A. Mohammed, Mohanad Hatem Shadhar, Ahmad Benwan Hassan, Pinank Patel, D. T. Arunkumar, Pragyan Paramita Pattnaik, Deepak Gupta, Y. Jatin Sharma, Sarfaraz Kamangar, Saiful Islam

{"title":"Graphene origami-reinforced cylindrical shells: free vibration analysis for enhanced structural performance","authors":"Zaid A. Mohammed, Mohanad Hatem Shadhar, Ahmad Benwan Hassan, Pinank Patel, D. T. Arunkumar, Pragyan Paramita Pattnaik, Deepak Gupta, Y. Jatin Sharma, Sarfaraz Kamangar, Saiful Islam","doi":"10.1007/s00707-025-04374-x","DOIUrl":"10.1007/s00707-025-04374-x","url":null,"abstract":"<div><p>This analytical paper investigates the impact of graphene origami as novel reinforcement on the vibrational characteristics of the cylindrical shells reinforced with a copper matrix including graphene origami metamaterials. The equations of motion are extracted using the Hamilton’s principle in which the constitutive relations using the shear deformable relation and the overall properties of constituent materials in the thermal environment. The shell is assumed constrained with simply and clamped boundary conditions. The Halpin–Tsai model is employed for derivation of the multi-dependent material properties. The analytical solution is proposed using the Navier and Galerkin approach for simply and other boundary conditions, respectively. The results will be presented parametrically with changes of graphene origami content and foldability as well as thermal load. The effect of small-scale parameter is studied on the natural frequency responses. A diminish in the frequencies is observed with an advance in the folding characteristics. The results of this study will be used for design and manufacturing the optimized composite structures with tuneable material properties and controllable responses.</p></div>","PeriodicalId":456,"journal":{"name":"Acta Mechanica","volume":"236 7","pages":"4197 - 4217"},"PeriodicalIF":2.9,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145162737","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}

引用次数: 0