Abstract
The clinical success of orthopedic implants in sports medicine depends on mechanical stability, yet conventional designs often trade off strength against stress shielding. We analyze functionally graded microstructure implants made of titanium and hydroxyapatite, with material properties varying through the thickness. To capture small-scale effects in additively manufactured microstructures, we adopt the modified couple stress theory. The governing equations come from energy method and are solved using a finite element method based on a higher-order shear deformation theory. A parametric study examines how the power law index, material length scale, boundary conditions, and porosity distribution affect the critical buckling load. Beyond traditional simulation, we implement an artificial neural network model to perform rapid stability analysis across the design space. The neural network, trained on finite element results, predicts critical buckling loads with high accuracy and significantly reduced computational cost. This allows real-time stability assessment for patient-specific implant geometries. Our combined approach shows that an optimal material gradation with porosity concentrated at the bioactive surface preserves mechanical integrity while promoting osseointegration. The findings offer a quantitative design framework that balances mechanical stability and biocompatibility, with direct relevance to load-bearing implants in sports medicine and orthopedics.
Key Words
artificial neural networks; buckling analysis; finite element method; functionally graded materials; implant stability; orthopedic biomechanics; optimization
Address
Yuan Wen, Defang Chen: College of Sports and Health, Nanchang Institute of Science and Technology, Nanchang 330100, Jiangxi, China
Yanfeng Dong: Department of Physical Education, Inner Mongolia Medical University, Hohhot 010000, Inner Mongolia Autonomous Region, China
Mostafa Habibi: Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, India/ Technical Sciences, Chennai, India/ Department of Mechanical Engineering, Faculty of Engineering, Haliç University, Istanbul, Turkey
Abstract
This paper investigates the electro-magneto-thermo-mechanical buckling behavior of a sandwich microplate. The structure consists of an elastic core integrated with piezoelectric/piezomagnetic face-sheets, accounting for significant small-scale effects. A higher-order shear and normal deformation theory is employed to accurately capture the plate's kinematics, including the crucial effect of thickness stretching. The constitutive relations are developed by coupling the generalized Hooke's law with the linear equations for piezoelectric and piezomagnetic materials. To incorporate size-dependent effects, the modified couple stress theory is integrated into the framework, introducing a single length scale parameter. The electric and magnetic potentials are modeled using a combination of a linear function, representing the applied external potential, and a trigonometric variation to satisfy the zero potential condition at the top/bottom surfaces. The results quantify the critical mechanical loads, temperature change, and electric and magnetic potentials, highlighting the influences of the micro-length scale, face-sheet to core thickness ratio, and elastic foundation parameters on the structural stability. This model can be applied to feedback control systems in intelligent civil engineering structures and composite load-bearing components of bridges.
Key Words
Hamilton's principle; higher-order modelling; multi-field loading; sandwich piezoelectric/ piezomagnetic microplate; scale-dependent model
Address
Lihong Lu: College of Civil Engineering and Architecture, Jiaozuo University, Jiaozuo 454000, Henan, China/ Jiaozuo Shengxin Environmental Protection Technology Co., Ltd., Jiaozuo 454006, Henan, China
Ting Li: School of Law and Journalism & Communication, Wuhan Donghu University, Wuhan 430212, Hubei, China
Mostafa Habibi: Department of Mechanical Engineering, Faculty of Engineering, Haliç University, Istanbul, Turkey/ Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, India
Abstract
The esophagus, a vital component of the digestive system, plays a pivotal role in ensuring the seamless passage of food from the mouth to the stomach. Its optimal functioning is imperative for our daily well-being, and any impairment can lead to significant complications, particularly in the form of dysphagia. This research addresses the pressing need for tailored dietary interventions for individuals grappling with dysphagia by leveraging insights gained from the analysis of two distinct types of esophageal model: one representative of a healthy state and the other simulating diseased conditions like no peristalsis and narrowing down near the lower esophageal sphincter (LES). Our study focuses on analyzing some distinct food items that are frequently given to patients and determining the optimal order for the food items based on how easily they pass through the esophagus to alleviate the challenges faced by dysphagia patients. A sensitive analysis has also been carried out to identify the specific property of the food items more susceptible to the variations in the desired output value, specifically wall shear stress for patients with and without dysphagia.
Key Words
dysphagia; lower esophageal sphincter; peristalsis; sensitive analysis
Address
Ankit Pal, Sriharsha Mishra, Soumyashree Nayak, Gaurav Kumar, Ashish Kumar Meher, Subrata Kumar Panda: Department of Mechanical Engineering, National Institute of Technology, Rourkela, Odisha, 769008, India
Naveen Kumar Akkasali: School of Mechanical Engineering, SASTRA Deemed University, Thanjavur, Tamilnadu, 6134001, India
Rama Chandra Pradhan: Department of Food Process and Engineering, National Institute of Technology, Rourkela, Odisha, 769008, India
Abstract
This study presents a comprehensive analytical investigation of the static bending behavior of functionally graded (FG) porous nanobeams incorporating size-dependent effects based on nonlocal strain gradient elasticity theory. A unified quasi-3D formulation with three displacement variables is developed, accounting for thickness stretching and higher-order shear deformation effects. The material properties are assumed to vary smoothly in both axial and transverse directions following power-law distributions, while different porosity patterns (even, uneven I, and uneven II) are considered to capture realistic material degradation. Three grading configurations, namely FG-2D, FG-T, and FG-A, are examined under various loading conditions (sinusoidal, uniform, and linear) and boundary constraints. The governing equations are derived using Hamilton's principle and solved via Galerkin's method. The influence of nonlocal parameter, length-scale parameter, porosity coefficient, and gradation indices on deflection and stress responses is systematically analyzed. The results reveal strong size-dependent behavior, where nonlocal effects tend to soften the structure while strain gradient effects introduce stiffness enhancement. Moreover, porosity significantly increases deflection and stress levels, while FG-A and FG-T configurations exhibit distinct stiffness characteristics compared to FG-2D. The proposed model demonstrates high accuracy, efficiency, and versatility in capturing the mechanical response of porous FG nanobeams.
Key Words
bending; elastic foundation effects; FGM; Galerkin method; porosity distribution; porous nanobeams; Quasi-3D beam model; size-dependent effects
Address
Ali Alnujaie: Department of Mechanical Engineering, College of Engineering and Copmuter Sciences, Jazan University, Jazan, Saudi Arabia/ Engineering and Technology Research Center, P.O. Box 114, Jazan 82817, Saudi Arabia
Ahmed A. Daikh: Artificial Intelligence Laboratory for Mechanical and Civil Structures, and Soil, University Centre of Naama, Naama 45000, Algeria
Amin Sami Hamdi: Department of Civil Engineering, Faculty of Engineering, King Abdulaziz University, Jeddah, Saudi Arabia
Azza M. Abdraboh: Physics Department, Faculty of Science, Benha University, Benha, Egypt
Amr E. Assie: Department of Mechanical Engineering, College of Engineering and Copmuter Sciences, Jazan University, Jazan, Saudi Arabia
Mohamed A Eltaher: Mechanical Engineering Department, Faculty of Engineering, King Abdulaziz University,
P.O. Box 80204, Jeddah 21589, Saudi Arabia/ Mechanical Design & Production Department, Faculty of Engineering, Zagazig University, Zagazig 44519, Egypt
Alaa A. Abdelrhmaan: Mechanical Design & Production Department, Faculty of Engineering, Zagazig University, Zagazig 44519, Egypt/ Jeddah International College (JIC), Jeddah, Saudi Arabia
Abstract
This study aims to examine the complex vibration properties of three-layer nanocomposite cylindrical sandwich shell structures that can be used for landscaping engineering design. This shell's composition includes a concrete core sandwiched between two nanoclay-reinforced composite face sheets, which enhance stiffness, damping capacity, and dynamic stability of the finished structure. Due to their lightweight properties coupled with their superior mechanical properties, nanocomposite sandwich shells offer additional benefits for sustainable landscaping infrastructure that is subjected to environmental and dynamic loading. The structural formulation used in this analysis is based upon the first-order shear deformation theory, which accounts for transverse shear effects in moderately thick shells, along with geometric nonlinearity resulting from large-amplitude deformation via the Von Kármán strain-displacement relations. The use of Hamilton's principle provides the basis for deriving the nonlinear governing equations and boundary conditions of the multilayer shell system analysis, while the application of a radial external force provides the ability to assess forced vibrations and nonlinear dynamic stability. Discretization of the nonlinear partial differential equations into ordinary differential equations is done, and these are solved numerically by means of a Runge-Kutta integration method to analyse nonlinear wave propagation, resonance characteristics, and the manner in which vibrations propagate through and under different excitation conditions, and varying geometries of shells and distributions of nanoclay reinforcement. Results indicate that nanoclay composite face sheets provide superior vibration suppression, provide a means for controlling the transmission of waves, and provide enhanced dynamic stability; thus, these types of shell structures are highly desirable for resilient and sustainable landscape engineering uses.
Key Words
cylindrical sandwich shell; landscape engineering design; nanoclay composite face sheets; nonlinear dynamic stability; Runge–Kutta time integration technique
Address
Yijun Wang, Yi Xu: School of Arts (School of Performing Arts), Sanjiang University, Nanjing, Jiangsu, 210012, China
Mengting Shen: College of Art, Tianping College of Suzhou University of Science and Technology, Suzhou, Jiangsu, 215009, China
Abstract
This study explores the effects of piezomagnetics on the dynamic behaviour and stability of functionally graded annular building plates for advanced civil and landscape engineering structures. This research is based on an eccentric rotating annular building plate that has a surface-bonded piezoelectric layer, which will provide more flexibility and control of vibrations and smart sensing capabilities in modern architectural and landscape uses. The annular building plate is also considered to be a functionally graded composite with continuous variation of material properties throughout the thickness of the plate, which enhances the distribution of stiffness, durability, and resistance to environmental loads that outdoor infrastructure systems encounter. Therefore, to accurately predict the results of the study, we will use a refined shear deformation theory (RSDT) as the basis for calculating transverse shear effects and do not need the need for a shear correction factor. The formulation of the nonlinear governing equations is obtained using the von Kármán strain-displacement relationship while including coupled magnetic/electric interactions, rotational inertia, and piezomagnetic effects in the equations. Hamilton's principle will be used to formulate a complete nonlinear dynamic formulation that incorporates both magnetic fields and electric fields. The equations resulting from this analysis have been solved via the transform differential quadrature method (TDQM), together with Newton's iterative scheme. Various parameter analyses indicate that material gradation and the influence of many nonlocal, strain-gradient, angular velocity, eccentricity, and multi-physics coupling parameters have a substantial impact on the dynamic stability behaviour of an annular building plate. The results obtained may also provide useful information in designing and optimizing a multitude of intelligent landscape structures, adaptive roof systems, and/or smart prefabricated construction components.
Key Words
dynamic stability; functionally graded annular plates; landscape structures; piezomagnetic effects; smart building systems
Abstract
The paper presents an innovative approach that is used to study the nonlinear dynamics of tennis rackets made of functionally graded materials strengthened by nano-structural elements and fully or partially immersed in fluids. The nanocomposite used in the structure is strengthened using GPLs, and their elastic properties are determined using the Halpin-Tsai method. The fluid is taken to be inviscid, incompressible, and irrotational with constant density. The hydrodynamic pressure is obtained based on Bernoulli's law. The nonlinear governing equations are developed based on von Karman theory. In order to address this highly nonlinear system, the isogeometric analysis (IGA) approach is chosen, which combines computer aided design and analysis in one integrated form. Both the method of harmonic balance and the arc-length continuation method are applied in order to trace periodic response behavior and bifurcations. This paper offers a reliable computational model to evaluate the dynamic behavior of GPL enhanced tennis racket in a fluid medium, considering the effect of the nanofiller layout, excitation strength, and fluid loading.
Address
Tao Zhang: Department of Physical Education, Guangzhou Vocational University of Science and Technology, Guangzhou, Guangdong 510555, China/ Graduate School, José Rizal University, Mandaluyong, Manila, 1552, Philippines
Abstract
The emergence of highly functionalized nanostructured architectures has paved the way for developing high-performance sports equipment that possess superior mechanical, vibrational, and dynamic properties. In this study, the architecture and stability analysis of advanced nanocomposites for sporting applications designed in the form of a doubly curved panel made of triply periodic minimal surface graphene origami auxetic metamaterials (TPMS-GOAM) are studied. The proposed nanoscale design uses the hierarchically structured pore networks to attain tunable stiffness, increased energy dissipation, and negative Poisson's ratio characteristics, which makes it appropriate for manufacturing next-generation lightweight sports equipment. The mechanics of the system are developed using the theory of the first-order shear deformation (FSDT) based on the Sanders shell theory. A shear correction factor is introduced to improve the consideration of transverse shear deformation within the nanolayered composite material arrangement. The governing equation of motion is established based on Hamilton's principle for an energy-based treatment of the bending-membrane interaction in curved forms. To solve numerically the governing equations, DQM is employed in which Lagrange interpolation and Chebyshev polynomial roots play key roles. The dynamic analysis of both free vibration and forced vibration is carried out to determine the vibration behavior of TPMS-GOEAM-based sport equipment subjected to dynamic loading. It is found through the parametric studies that the vibration behavior of the composite nanoscale structure is significantly affected by the porosity distribution, curvature ratio, and GOEAM reconfiguration. The study finds that the proposed composite nanomaterial structure exhibits better dynamic stability and vibration isolation than traditional composite structures for sport equipment in terms of the frequency content, mode shape, and dynamic magnification factor.
Key Words
doubly curved panel; dynamic stability; external excitation; nanocomposite sport equipment; TPMS-GOEAM
Address
Wangyang Liu: School of Physical Education, Hanjiang Normal University, Shiyan, Hubei 442000, China
Tong Xu: Wuhan College of Arts & Science, WuHan, Hubei 430345, China/ Singapore Amity Global Academy Teesside University, UK, 228 Orchard Road, 238853, Singapore
Shiyao Zhu: School of Physical Education and Sports, Central China Normal University, WuHan, Hubei 430079, China
Bo Huang: School of Physical Education of Wuhan University of Technology, WuHan, Hubei 430070, China
