Archive of Applied Mechanics最新文献

{"title":"Study of an arbitrarily oriented mode-III crack using gradient elasticity theory in a bidirectional functionally graded material","authors":"Kamlesh Jangid,&nbsp;Rakesh Kumar Sharma,&nbsp;Y. Eugene Pak","doi":"10.1007/s00419-025-02792-w","DOIUrl":"10.1007/s00419-025-02792-w","url":null,"abstract":"<div><p>In this research, we conduct a thorough analysis of an arbitrarily oriented mode-III crack in a bidirectional functionally graded material (FGM) using strain gradient elasticity (SGE) theory. The focus is on understanding the growth and behavior of the crack when it is positioned at an angle counterclockwise to the <i>x</i>-axis. The material gradation in the bidirectional FGM is assumed to follow an exponential distribution within the <i>xy</i>-plane. By transforming the global coordinate system into a local system, the <span>(x_1)</span>-axis is aligned with the crack’s direction, forming a specific angle with the <i>x</i>-axis. The SGE theory uses two material characteristic lengths, <span>(ell )</span> and <span>(ell ^prime )</span>, to account for volumetric and surface strain gradient factors, respectively. To solve the crack boundary value problem, we utilize a methodology that combines Fourier transforms with an innovative hyper-singular integrodifferential equation approach. This methodological framework allows us to derive a comprehensive system of equations, which are then solved using Chebyshev polynomial expansion techniques and the selection of suitable collocation points. Our study includes a detailed examination of the crack surface displacement under various material parameter configurations. We also analyze the stress intensity factors and the energy release rate at the crack tips, providing critical insights into the mechanical behavior of cracks in bidirectional FGMs under the influence of strain gradient elasticity.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 4","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688543","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":"Modeling the viscoelastic behavior of a FG nonlocal beam with deformable boundaries based on hybrid machine learning and semi-analytical approaches","authors":"Aiman Tariq,&nbsp;Hayrullah Gün Kadıoğlu,&nbsp;Büşra Uzun,&nbsp;Babür Deliktaş,&nbsp;Mustafa Özgur Yaylı","doi":"10.1007/s00419-025-02776-w","DOIUrl":"10.1007/s00419-025-02776-w","url":null,"abstract":"<div><p>This study investigates the free vibration behavior of Euler–Bernoulli beams made of viscoelastic materials using nonlocal theory. The mechanical properties of the nanobeam are functionally graded through its thickness, and the viscoelastic effects on energy damping are considered. Furthermore, micro- and nano-scale structural effects are incorporated into the model using nonlocal elasticity theory. Based on this, a semi-analytical solution method is developed to determine the natural frequencies and damping ratios of the beam under elastic boundary conditions. The effects of various parameters such as geometry, material grading, viscoelastic properties, and nonlocality on the dynamic behavior of beam are studied using this solution, and the results are compared with other studies in literature. Subsequently, a space-filling sampling technique is used to generate well-distributed samples of input parameters uniformly across an input space. The generated dataset is used to train various machine learning (ML) models such as k-nearest neighbor, decision tree regression, extreme gradient boosting, and light gradient boosting. Various hyperparameter optimization techniques including metaheuristic algorithms (particle swarm and genetic algorithms) and model-based methods (Bayesian optimization with Gaussian process and tree-structured Parzen estimator) are explored. A detailed study is conducted to identify the most efficient optimization technique with the most robust ML model. It is found that the decision tree regression incorporated into Bayesian optimization with tree-structured Parzen estimator) achieves the best performance in terms of computational cost and accuracy. This hybrid model requires only 11.64 s to train and perfectly predicts vibration frequencies with coefficient of determination (<i>R</i>²) of 1. The model's robustness is further validated using comprehensive statistical and graphical evaluations.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 4","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00419-025-02776-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143655203","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":"Evaluation of the contact problem of two layers one of functionally graded, loaded by circular rigid block and resting on a Pasternak foundation by analytical and numerical (FEM and MLP) methods","authors":"Murat Yaylacı,&nbsp;Aleyna Yazıcıoğlu,&nbsp;Ecren Uzun Yaylacı,&nbsp;Merve Terzi,&nbsp;Ahmet Birinci","doi":"10.1007/s00419-025-02787-7","DOIUrl":"10.1007/s00419-025-02787-7","url":null,"abstract":"<div><p>In this paper, the frictionless contact problem of layers on a Pasternak foundation is addressed using various methods, such as the analytical method, finite element method (FEM), and multilayer perceptron (MLP). The problem consists of two layers: The upper layer is homogeneous (HOM), while the lower layer is functionally graded (FG). The upper layer is loaded by a circular rigid block that applies a concentrated force, and Poisson’s ratios of the layers are kept constant. In the solution, the weights of both layers are neglected, and stress due to pressure is considered. First, the problem is solved analytically using the theory of elasticity and integral transformation techniques. In this method, the equations governing the stress and displacement components of the layers are transformed into a system of two singular integral equations involving unknown contact pressures and contact lengths using Fourier transform techniques and boundary conditions. The integral equations are solved numerically using the Gauss–Chebyshev integration formula. Then, the finite element solution of the problem was performed using the ANSYS package program, which is based on the finite element method. Finally, the problem was solved with a multilayer perceptron (MLP), an artificial neural network for different problem parameters. The results obtained with all three methods were compared and interpreted. It is clear from the results that the contact pressure and contact length vary depending on various parameters such as block radius, stiffness parameter, shear modulus ratios, and Pasternak soil parameters.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 4","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00419-025-02787-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645524","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 Moore Gibson–Thompson effects on wave propagation and reflection in nonlocal solid medium","authors":"Amara Zaheer,&nbsp;Hashmat Ali,&nbsp;Ehtsham Azhar,&nbsp;Muhammad Jamal","doi":"10.1007/s00419-025-02784-w","DOIUrl":"10.1007/s00419-025-02784-w","url":null,"abstract":"<div><p>In this paper, the wave propagation and reflection are studied in nonlocal solid under the impact of Moore Gibson–Thompson model. The governing equations are Helmholtzed and converted into the homogeneous algebraic system of equations. The algebraic equations have non-trivial solutions that can provide the dispersion relation associated with propagation speed. Two coupled longitudinal waves (P-waves and T-waves) and one transverse wave (SV-wave) can be obtained from the dispersion relation. In this case, the ratios of the amplitudes of the reflected waves are calculated analytically by imposing a given set of appropriate boundary conditions. The amplitude ratio and propagation speed are also plotted graphically. The influence of nonlocality and thermal relaxation time parameter on the gained results is examined and visualized through graphical representations. Optimal results are obtained by neglecting the thermal relaxation time parameter.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622239","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":"Numerical simulation analysis of the axial compressive performance of UHPC hoop-restrained reinforced concrete columns","authors":"Jia Rong Zhao,&nbsp;Yu Qin Long,&nbsp;Cong Chun Chen,&nbsp;Xiao Liu,&nbsp;Qian Wan,&nbsp;Wei Zhang","doi":"10.1007/s00419-025-02780-0","DOIUrl":"10.1007/s00419-025-02780-0","url":null,"abstract":"<div><p>To investigate the axial compressive behavior of reinforced concrete (RC) square columns enhanced with ultra-high-performance concrete (UHPC) under specific conditions, a composite column model comprising \"UHPC + steel mesh\" was developed using finite element analysis software. This approach distinguishes between confined and unconfined zones within the column. The study examined the effects of UHPC shell thickness, longitudinal bar spacing, and stirrup spacing on the axial compression characteristics, failure mechanisms, and load-bearing capacity of RC square columns. The results indicate that increasing the thickness of the UHPC shell significantly enhances load capacity from 2172 kN to 5132 kN while concurrently reducing ductility. In contrast, reducing stirrup spacing has a minimal effect, yielding an increase in load capacity of only 806 kN. Adjusting the longitudinal rib spacing greatly enhances ductility while concurrently achieving a comparable increase in load capacity, namely by 704 kN. The suggested calculation model for the RC was theoretically validated against the restricted concrete theory and shown strong concordance with experimental data.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143583478","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":"Eigencharacteristics and nonlinear response of partially submerged flexible L-shaped beam with eccentric tip mass","authors":"Pravesh Kumar","doi":"10.1007/s00419-025-02782-y","DOIUrl":"10.1007/s00419-025-02782-y","url":null,"abstract":"<div><p>In this work, free and forced vibration analysis of a partially submerged flexible L-shaped offshore structure carrying concentrated eccentric tip mass is presented. The column is modelled as interconnected Euler–Bernoulli beam elements having fixed condition at proximal end and carrying a concentrated mass at the terminal end. The governing equations of motion describing system’s behaviour in transverse and longitudinal direction are  derived using multi-body system approach. The variable separable method is used to obtain the eigenfrequency equation of fluid–structure system, and exact solutions are graphically presented. The influence of depth of immersion, added tip mass and its eccentricity on the eigenfrequency of the column, is reported. The results obtained are verified with the existing literature as well as FEA simulations for the limiting cases of depth of immersion and varying tip mass. Further, the mode shape functions and eigenfrequency parameters are used in conjunction with Galerkin’s method to obtain nonlinear model of the system under bi-directional time-dependent base excitations. The large deformation of the beams is under consideration, and inextensibility condition is used to incorporate the longitudinal deformation effects in transverse direction. The steady-state solutions of the system under combined external and inherent 1:1 internal resonance conditions are obtained using perturbation method. The existence of multiple jump phenomena and multi-valued solutions are explored through frequency response curves. The system exhibits combination of saddle-node and pitchfork bifurcations leading to instability in the system responses due to sudden change in amplitudes at critical points. The obtained results are compared with the numerical solutions to achieve the close agreement. The system is found to undergo large-amplitude vibrations at critical values axial and transverse base excitation frequencies. The fluid interaction with the structure has a stabilizing influence on the frequency response, while increase in the tip mass leads to increase in vibration amplitude of the system. The first and second beam exhibit frequency response of different features due to the nature of geometric nonlinearities. The effect of essential system parameters on the column’s responses has been analysed graphically, and vulnerability of system’s stability is also discussed graphically.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00419-025-02782-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581164","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":"The instability of plant ribbons in orthotropic materials induced by growth strain","authors":"Di-Quan Wu,&nbsp;Mohamad Ikhwan Zaini Ridzwan","doi":"10.1007/s00419-025-02783-x","DOIUrl":"10.1007/s00419-025-02783-x","url":null,"abstract":"<div><p>The aim of this paper is to investigate the influence of orthotropic material parameters on the buckling behavior of infinitely long ribbons induced by growth strain under natural boundary conditions, encompassing both linear buckling and post-buckling analyses. The ribbons were initially modeled as infinitely long elastic plates, and the boundary value problem related to their buckling behavior was formulated. This study adeptly employed the form functions of the ribbon during filamentary, saddle, and small amount torsion stages. We effectively decoupled these equations into ordinary differential equations through the method of separation of variables, subsequently solving them numerically using the BVP5C function in MATLAB to research the behavior of the ribbon across these buckling phases. The results show that the elastic modulus ratio, shear modulus ratio, and Poisson’s ratio in the elastic principal plane affect the ribbons behavior of filament buckling, saddle buckling, and small amount torsion stage to varying degrees, respectively, when the ribbon exhibits natural differential growth along the principal axis of the orthogonal material. The findings of this research are anticipated to yield novel insights into the understanding and regulation of the morphological evolution of soft materials derived from either natural or engineered composites.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00419-025-02783-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581196","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":"Impact of activation energy and electroosmosis on peristaltic flow of Pseudoplastic nanofluids in an asymmetric channel","authors":"P. Tamizharasi,&nbsp;Y. Akbar,&nbsp;A. Magesh","doi":"10.1007/s00419-025-02778-8","DOIUrl":"10.1007/s00419-025-02778-8","url":null,"abstract":"<div><p>The present research investigates the effects of activation energy and electroosmosis on the peristaltic transport of a pseudoplastic nanofluid flowing through an asymmetric, flexible microchannel. The analysis incorporates crucial factors, such as thermal radiation, magnetic field, thermophoresis, and Brownian motion. The governing mathematical model is simplified using the lubrication approximation. The resulting system of equations is then numerically solved using NDSolve in Mathematica. The impact of key fluid properties on electroosmotic flow is examined through graphical analysis. Results demonstrate that nanofluid velocity decreases with increasing Debye–Hückel parameter. Furthermore, fluid flow is reduced with higher pseudoplastic fluid parameters, while nanoparticle concentration diminishes with increasing temperature ratio parameters. Nanofluid temperature increases with an enhancement in the thermophoresis parameter.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554008","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":"Deformation behavior of hard-magnetic soft material beams under combined magnetic and mechanical forces","authors":"Yibin Mai,&nbsp;Jinhui Yang,&nbsp;Wei Gao","doi":"10.1007/s00419-025-02777-9","DOIUrl":"10.1007/s00419-025-02777-9","url":null,"abstract":"<div><p>This paper presents a theoretical model for a two-dimensional hard-magnetic soft material (HMSM) beam under combined mechanical loads and magnetic fields, based on Euler–Bernoulli beam theory. The model is validated by comparison with existing literature. Numerical simulations show that the deformation of HMSM beams is highly sensitive to the magnitude and direction of the applied mechanical and magnetic fields. Small variations in these parameters lead to significant changes in the beam's shape and response. When the external force and magnetic field are of similar magnitude, strong magneto-mechanical coupling results in pronounced bending deformation. In contrast, when the external force is much smaller than the magnetic field, the magnetic field dominates the overall deformation, while the external force subtly adjusts the bending angle. These findings provide valuable insights for optimizing HMSM-based materials in adaptive and multifunctional applications. For instance, in HMSM-based soft robots operating in confined spaces (e.g., blood vessels or pipelines), the model helps predict deformation behavior while accounting for mechanical interactions with the surrounding environment, such as friction and normal forces from vessel or pipeline walls.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553997","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 comparative study on the effectiveness, robustness and mistuning sensitivity of upgraded tuned mass dampers in mitigating the dynamic response of civil structures","authors":"Huong Quoc Cao","doi":"10.1007/s00419-025-02781-z","DOIUrl":"10.1007/s00419-025-02781-z","url":null,"abstract":"<div><p>Upgraded tuned liquid column damper (UTLCD), tuned two-mass damper (TTMD) and double-tuned mass damper (DTMD) have been recently introduced by Cao and his research group. However, mistuning sensitivity related to the frequency and damping ratios of these absorbers, along with a comparative study of the devices, has not been investigated. To address the gaps in the previous studies, a comprehensive comparative study on the performance, robustness and mistuning sensitivity of UTLCD, TTMD and DTMD is conducted in this paper. To do this, analytical models of a single-degree-of-freedom (SDOF) structure equipped with a UTLCD, TTMD and DTMD are established. Using a novel optimization technique named balancing composite motion optimization (BCMO), the optimal parameters of these passive dampers are found. After that, the control effectiveness, the robustness against the changes in the structural properties, and the mistuning sensitivity of each vibration absorber are determined. For the optimal configurations of UTLCD, TTMD and DTMD having the same weight, this study indicates that although the UTLCD is the most effective compared with the TTMD and DTMD, it is not as robust as the TTMD or DTMD against the variation of the mass, stiffness and damping coefficient of the primary structure. The DTMD is as effective and robust as the TTMD. Furthermore, the mistuning sensitivity of the UTLCD is similar to that of the DTMD. While the sensitivity regarding the damping ratio of the UTLCD is the lowest, the damping ratio sensitivity of the TTMD is the highest.</p></div>","PeriodicalId":477,"journal":{"name":"Archive of Applied Mechanics","volume":"95 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00419-025-02781-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529994","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}