Article
Chemistry, Physical
Feixiang Tang, Siyu He, Shaonan Shi, Shun Xue, Fang Dong, Sheng Liu
Summary: The purpose of this paper is to study the bending, buckling, and vibration of micro-thin plates by considering the micro-scale effects. The results show that the scale effect increases the equivalent stiffness of the thin plate, leading to a decrease in deflection, a larger critical buckling load, and an increase in natural frequency, but does not affect the buckling topography. The findings of this research may contribute to the design of micro-scale devices such as MEMSs/NEMSs.
Article
Acoustics
Iman Ghaffari, Ardeshir Karami Mohammadi
Summary: This study analyzes the nonlinear free vibrations of a sandwiched microbeam with a shape memory alloy core and provides a better understanding of the design of such microbeams through comparison with previous studies.
JOURNAL OF VIBRATION AND CONTROL
(2022)
Article
Engineering, Multidisciplinary
Yu-fang Zheng, Li-Chuan Liu, De-yong Qu, Chang-ping Chen
Summary: This article presents the nonlinear postbuckling behavior of magneto-electro-thermo-elastic (METE) laminated microbeams. Based on the modified couple stress theory and Reddy's three-order shear deformation theory, along with the von Karman geometric nonlinearity, the nonlinear static model of METE laminated microbeam is established. The nonlinear governing equations and boundary conditions are derived using the principle of virtual work principle. An analytical method is then used to describe the nonlinear postbuckling behavior of METE laminated microbeam with simple supported and clamped boundary conditions. Numerical examples are provided to reveal the effects of various parameters on the critical buckling load and postbuckling response, as well as the distribution of magneto-electric potential through the thickness direction of the microbeam with different lay-up modes.
APPLIED MATHEMATICAL MODELLING
(2023)
Article
Mechanics
Ahmed Saimi, Ismail Bensaid, Omer Civalek
Summary: This work investigates the free vibratory behavior of imperfect BD-FG microbeams with cracks using the Quasi-3D shear and normal deformation beam concept, Modified Couple Stress Theory, and Differential Quadrature Finite Element Method. The obtained outcomes are validated with the literature results to show the efficiency and accuracy of the numerical resolution method. The findings can be applied for the design of porous FG microstructures in engineering.
COMPOSITE STRUCTURES
(2023)
Article
Acoustics
Mohammad Javad Ashrafi, Iman Ghaffari, Mohammad Elahinia, Mohammad Reza Nematollahi
Summary: This study evaluates the size effects on the nonlinear free vibration of the sandwich composite microbeam, finding that increasing the material length scale to thickness ratio decreases damping capacity.
JOURNAL OF VIBRATION AND CONTROL
(2021)
Article
Multidisciplinary Sciences
Rong Zhang, Hongbai Bai, Xiaochao Chen
Summary: The present study aims to investigate the free vibration, buckling, and post-buckling behaviors of bidirectional functionally graded microbeams. The governing equations and boundary conditions of the microbeams were formulated using the Timoshenko beam theory and the consistent couple stress theory. Parametric investigations were carried out to analyze the effects of material distribution functions, length to thickness ratio, gradient indexes, and size effect on the vibration and buckling behaviors of the microbeams under different boundary conditions.
Article
Engineering, Civil
Ehsan Raeisi Estabragh, Gholam Hossein Baradaran
Summary: In this study, a numerical model for the large amplitude free vibration of nanobeams based on the modified couple stress theory was developed, showing the importance of considering the effects of dimensionless length scale parameter, slenderness ratio, vibration amplitude, and different boundary conditions in the free vibration analysis of nanobeams when considering nonlinear and size effects.
INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
(2021)
Article
Chemistry, Physical
Sirri Can Polat, Sueleyman Murat Bagdatli
Summary: In this study, the linear and nonlinear vibration movements of simply supported stepped microbeams placed in a magnetic field were analyzed using Modified Couple Stress Theory. The equations of motion of the stepped-microbeam were obtained by considering the step radius ratio, step-change position, and material size parameter, and then nondimensionalized to eliminate dependence on material type and geometric structure. The approximate solution of the dimensionless equations of motion was calculated using the method of multiple scales. The study investigated the linear and nonlinear problems separately, addressing the natural frequencies of the system, the effects of step radius ratio, step-change position, and microbeam coefficient, and examined the resonance state and stability analysis.
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION A-A JOURNAL OF PHYSICAL SCIENCES
(2023)
Article
Mechanics
Aref Mehditabar, Saeid Ansari Sadrabadi, Jason Walker
Summary: This study investigates the thermal buckling responses of a functionally graded cylindrical microshell. The material properties of the microshell are graded through the thickness based on a simple power-law distribution. The governing equations and boundary conditions are derived using higher-order shear deformation theory. The size dependence of the microshell is characterized using the modified couple stress theory. Two types of differential quadrature method are employed to solve the equations and obtain the critical buckling temperature. The numerical technique shows fast convergence and is validated against available data. Parametric studies are conducted to analyze the influence of various factors on the critical buckling temperature.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Mathematics
Khalid H. Almitani, Nazira Mohamed, Mashhour A. Alazwari, Salwa A. Mohamed, Mohamed A. Eltaher
Summary: This paper presents exact solutions for the nonlinear bending problem, buckling loads, and postbuckling configurations of a bioinspired helicoidal composite beam. The proposed model is validated and the effects of various factors on the nonlinear bending, critical buckling loads, and postbuckling configurations are discussed.
Article
Physics, Multidisciplinary
M. Alimoradzadeh, S. D. Akbas
Summary: This paper investigates the nonlinear dynamic behavior of cracked AFM under external influences, analyzes the effects of various parameters on its stability through numerical examples, and identifies the corresponding unstable regions.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Mechanics
Kaveh Rashvand, Akbar Alibeigloo, Mehran Safarpour
Summary: This study investigates the influence of viscoelastic coefficient and material length scale parameter on the frequency of a micro-shell, as well as the effects of conveying fluid and temperature changes. The findings suggest that the viscoelastic coefficient and fluid flow have significant impacts on the stability of the micro-shell.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Physics, Multidisciplinary
Esmail Zarezadeh, Javad Eshaghi, Abbas Barati
Summary: This study investigates the instability behavior of two types of microswitches, cantilever and clamped, which are electrostatically excited in the presence of a uniform longitudinal magnetic field. The microswitches are modeled with a microbeam made of functionally graded material. The size effects on the pull-in instability are captured using the modified couple stress theory, and the displacement and rotation field of the microbeam are obtained using the Bernoulli-Euler beam hypothesis. The results show good agreement with available literature results and the effect of material and geometry properties on the pull-in voltage is investigated.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Mathematics
Nazira Mohamed, Salwa A. Mohamed, Mohamed A. Eltaher
Summary: This manuscript presents a mathematical model to predict the buckling, postbuckling, and nonlinear bending of imperfect bio-inspired helicoidal composite beams with nonlinear rotation angle. The model is validated through numerical studies, and the effect of rotation angle, imperfection amplitude, and foundation stiffness on the beams' behavior is quantified. The results show that the proposed model can be applied to the analysis of bio-inspired structures in engineering applications.
Article
Mechanics
Richa Priyanka, Jeyaraj Pitchaimani
Summary: This paper investigates the buckling and free vibration behaviors of micro laminated composite beams under varying axial loads using the modified couple stress theory, capturing the size effect by considering material length scale parameters and exploring different boundary conditions and layups. The observed size effect is more significant when the beam thickness is similar to the material length scale parameter and diminishes as the thickness increases. Different boundary conditions result in varying small size effect variations, with the fundamental frequency decreasing more rapidly under parabolic loading compared to other loading types.
COMPOSITE STRUCTURES
(2022)
Article
Mechanics
X. L. Zhang, Q. Xu, X. Zhao, Y. H. Li, J. Yang
COMPOSITE STRUCTURES
(2020)
Article
Engineering, Mechanical
Youheng Dong, Xiangyu Li, Kang Gao, Yinghui Li, Jie Yang
NONLINEAR DYNAMICS
(2020)
Article
Mechanics
Chang-Cheng Du, Ying-Hui Li
COMPOSITE STRUCTURES
(2020)
Article
Acoustics
X. Zhao, B. Chen, Y. H. Li, W. D. Zhu, F. J. Nkiegaing, Y. B. Shao
JOURNAL OF SOUND AND VIBRATION
(2020)
Article
Engineering, Multidisciplinary
Youheng Dong, Yinghui Li, Xiangyu Li, Jie Yang
APPLIED MATHEMATICAL MODELLING
(2020)
Article
Engineering, Mechanical
Bo Zhu, Xiao-Chao Chen, Yang Guo, Ying-Hui Li
Summary: This study investigates the static and dynamic responses of functionally graded material (FGM) pipes with porosities and geometric imperfections. Nonlinear equations of motion incorporating von Korman nonlinearity and initial imperfection are derived, and closed-form solutions for critical buckling velocity and stability behavior under different boundary conditions are proposed. The effects of important parameters on buckling and post-buckling behavior are explored in numerical results.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Acoustics
Yixin Lu, Xiaochao Chen
SHOCK AND VIBRATION
(2020)
Article
Materials Science, Multidisciplinary
Xin Xue, Shixin Ruan, Hongbai Bai, Xiaochao Chen, Yichuan Shao, Chunhong Lu
MECHANICS OF MATERIALS
(2020)
Article
Engineering, Multidisciplinary
M. Li, Q. Xu, X. C. Chen, X. L. Zhang, Y. H. Li
APPLIED MATHEMATICAL MODELLING
(2020)
Article
Engineering, Multidisciplinary
Xiaochao Chen, Lunting Chen, Songbin Huang, Ming Li, Xiao Li
Summary: This research investigates the nonlinear vibration of in-plane bi-directional functionally graded plates with global and localized geometrical imperfections under transverse harmonic excitation. The study shows that variations in gradient parameters and the presence of geometrical imperfections can alter the nonlinearity of resonant response, leading to phenomena such as cyclic-fold, period doubling, and torus bifurcations of the periodic solution. Additionally, the effects of functional gradient parameters, external excitation parameters, and damping coefficients on dynamic responses are examined.
APPLIED MATHEMATICAL MODELLING
(2021)
Article
Acoustics
Jianqiang Wu, Lunting Chen, Ruixian Wu, Xiaochao Chen
Summary: The study investigates the nonlinear forced vibration of bidirectional functionally graded porous material beams with material components gradient changes in both thickness and axial directions. Utilizing von Karman's geometric nonlinearity and first-order shear deformation theory, the governing equations for the coupled deformations are formulated as a system of nonlinear partial differential equations. The effects of system parameters such as gradient indexes, porosity, damping coefficients, and aspect ratio are examined through numerical results.
SHOCK AND VIBRATION
(2021)
Article
Mechanics
Xiaochao Chen, Lunting Chen, Yixin Lu
Summary: This research examines the sensitivity of imperfections in the nonlinear resonance behavior of BDFG porous beams, utilizing theoretical models and numerical methods to uncover various types of nonlinear characteristics that may occur during resonance response.
COMPOSITE STRUCTURES
(2021)
Article
Chemistry, Physical
Xiao Li, Wentao Jiang, Xiaochao Chen, Zhihong Zhou
Summary: This study focuses on the nonlinear vibration of rotating composite laminated cylindrical shells under hygrothermal environment and radial harmonic excitation. Nonlinear partial differential equations of the shells are derived considering various factors, and analytical solutions are obtained using the Galerkin approach and multiple scales method. The results suggest interesting insights into amplitude-frequency relations and nonlinear dynamic responses of the shells, particularly in terms of the combined effects of temperature and moisture concentration on nonlinear resonance behavior.
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION A-A JOURNAL OF PHYSICAL SCIENCES
(2021)
Article
Engineering, Aerospace
X. L. Zhang, X. C. Chen, M. Li, Y. H. Li, J. Xu
Summary: This paper investigates the thermal post-buckling behaviors of magneto-electro-elastic laminated beams, modeling the beams using Timoshenko beam theory with von Karman geometric nonlinearity. The study focuses on thermal post-buckling paths, post-buckling vibration characteristics, and magneto-electric potential responses, discussing the effects of lay-up modes, thermal load types, and magneto-electric fields.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Mechanical
M. Li, X. C. Chen, X. P. Chang, Y. Qin, Y. H. Li
Summary: This study presents a general analytical solution for vibrations of oil-conveying pipes, using generalized functions and Laplace transform to handle discontinuities. Numerical tests validate the feasibility and effectiveness of the solutions, while discussing the impact of physical parameters on natural frequencies.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
