Article
Engineering, Marine
C. C. Hong
Summary: In this study, the effects of the third-order shear deformation theory (TSDT) on thick functionally graded material (FGM) plates-cylindrical shells under thermal vibration were investigated using the generalized differential quadrature (GDQ) method. The results show that the advanced nonlinear shear correction, FGM power law index, and environment temperature have significant influences on the thermal stress and center displacement of FGM plates-cylindrical shells.
Article
Engineering, Aerospace
Bo Wang, Yan Wang, Kuo Tian, Yan Zhou, Shengli Xu, Haixin Zhao
Summary: This study proposes a global-local collaborative optimization method for the layout of stiffeners in a stiffened cylindrical shell with a cutout. By using the sequential sampling method and radial basis function surrogate model, the optimal global stiffener layout and layout around the cutout are obtained collaboratively. An illustrative example shows the effectiveness of the method, resulting in reduced weight and maximum stress compared to noncollaborative optimization methods.
Article
Materials Science, Multidisciplinary
C. C. Hong
Summary: The effects of the third-order shear deformation theory (TSDT) on thick functionally graded material (FGM) plates under thermal vibration are investigated using the generalized differential quadrature (GDQ) method. The equations of motion for thermal vibration of thick FGM plates are derived using the nonlinear coefficient term of the displacement field of TSDT. The dynamic equilibrium differential equations of FGM plates, considering the simplified stiffness under linear temperature rise, are derived in terms of partial derivatives of displacements, shear rotations, thermal loads, mechanical loads, and inertia terms. The effects of two parameters, environment temperature and FGM power law index, on the thermal stress and center deflection of FGM thick plates are investigated.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2023)
Article
Engineering, Mechanical
Chih-Chiang Hong
Summary: The effects of TSDT on the thermal vibration of thick FGM spherical shells were investigated using the GDQ numerical method. The inclusion of the c(1) term of nonlinear coefficient in TSDT displacement helped obtain dynamic GDQ discrete equations. Parametric variables such as environment temperature, FGM power law index, and calculated shear coefficient were found to have significant effects on stress and center deflection in thick FGM spherical shells.
INTERNATIONAL JOURNAL OF MECHANICS AND MATERIALS IN DESIGN
(2021)
Article
Engineering, Civil
Haigui Fan, Longhua Li, Wenguang Gu, Peiqi Liu, Dapeng Hu
Summary: This paper applies the energy barrier approach to the buckling design of axially compressed stiffened cylindrical shells. The reliability and advantage of the method are verified through experimental data comparison and numerical research, and the design of high buckling loads and low imperfection sensitivity is successfully achieved for the stiffened cylindrical shells.
THIN-WALLED STRUCTURES
(2022)
Article
Engineering, Mechanical
Lu Zhang, Ming Li, Changliang Lai, Weiping He, Shiyang Zhu, Hualin Fan
Summary: A unified computational framework was developed to analyze multiple buckling modes of stiffened cylindrical shells under hydrostatic pressure. The framework can predict overall buckling, tripping, and coupled shell-stiffener buckling simultaneously. The research provides a reference for the design of submerged composite stiffened cylindrical shells.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Marine
Zhanzhong Sun, Gangyi Hu, Xueyang Nie, Jiabin Sun
Summary: In this paper, a novel analytical approach based on symplectic mechanics is proposed for the buckling analysis of ring-stiffened porous graphene platelet-reinforced composite cylindrical shells under hydrostatic pressure. The approach transforms the governing equations into a set of Hamiltonian canonical equations, allowing for the simultaneous determination of accurate critical pressures and analytical buckling mode shapes without trial functions. The numerical results show good agreement with existing results, and a comprehensive parametric study is also conducted.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Mechanics
Dang Thuy Dong, Pham Thanh Hieu, Vu Minh Duc, Nguyen Thi Phuong, Nguyen Van Tien, Vu Hoai Nam
Summary: The nonlinear buckling behavior of CNT-reinforced cylindrical shells with CNT-reinforced stiffeners under external pressure considering the effects of uniform temperature rise is studied in this paper. A new design of stiffener system is proposed for the CNT-reinforced cylindrical shells with five different cases of CNT distribution law. A modified homogenization technique for CNT-reinforced stiffeners is developed. By applying the Galerkin method with the solution of deflection approximated in three-term form based on the Donnell shell theory and the von Karman nonlinearity assumption, explicit expressions for critical buckling and load-deflection postbuckling curves are obtained.
MECHANICS OF COMPOSITE MATERIALS
(2023)
Article
Engineering, Civil
Yang Yang, Jun-Jian Li, Yu Zhang, Qi He, Hong-Liang Dai
Summary: This paper investigates the strength and buckling behavior analysis of a ring-stiffened cylindrical shell for sightseeing submersibles under mechanical and thermal loads. It shows that external load has the most significant influence on the shell's strength, while shell thickness has the most obvious effect on its buckling load.
ENGINEERING STRUCTURES
(2021)
Article
Mechanics
Weifu Sun, Tingting Zhu, Yinan Qiu, Gaojian Lin
Summary: This paper investigates the prediction of the buckling strength of stiffened cylindrical shells based on the non-destructive probing technique. Finite element simulations are used to determine the proper probing location with respect to the stiffener. Lateral probing experiments are conducted to validate the simulation results. It is found that the height of the stiffener and the probing location are two important factors affecting the accuracy of the buckling load prediction.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2023)
Article
Engineering, Civil
Pascal Ventura, Hamza Azzayani, Hamid Zahrouni, Michel Potier-Ferry
Summary: In this paper, the buckling of elastic thin structures, specifically cylindrical shells under external pressure, is numerically analyzed using the Asymptotic Numerical Method (ANM) and Pade approximants. The perturbation technique is applied to both conservative and non-conservative loadings. The study utilizes a shell formulation suitable for thin structures, incorporating the Enhanced Assumed Strain (EAS) concept and a three-dimensional constitutive law without condensation. Numerical examples are presented, comparing critical pressure for conservative and non-conservative loading.
THIN-WALLED STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Xiaoming Cao, Lei Wang, Zhao Li, Hao Zhang, Xinliang Wang
Summary: This paper presents an analytical approach based on layerwise theory for the global buckling analysis of ring-stiffened sandwich cylindrical shells. The critical buckling load is obtained using the Rayleigh-Ritz method. Numerical simulations using Abaqus FEM software confirm the accuracy of the proposed method, and the effects of shell thicknesses and rib parameters on buckling performance are explored.
FRONTIERS IN MATERIALS
(2022)
Article
Acoustics
Yuhang Yang, Tiangui Ye, Shuaijun LI, Guoyong Jin, Yukun Chen, Saifeng Zhong
Summary: This paper proposes a semi-analytical model to describe the vibro-acoustic characteristics of submerged orthogonal stiffened laminated cylindrical shells. The displacement field is described using the first-order shear deformation theory combined with the Lekhnitsky smeared stiffener technique, and the sound field is modeled using the spectral boundary element method. The shell is divided into main structures with additional stiffness and mass of smeared stiffeners, which are further separated into sub-segments to ensure high accuracy of acoustic calculations. The developed model demonstrates high accuracy through comparison with literature, and the influences of different factors on the vibro-acoustic characteristics of orthogonal stiffened laminated cylindrical shells are investigated.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Civil
Yongmei Zhu, Wei Guan, Weili Wang, Cunhao Dong, Jian Zhang
Summary: This study numerically and experimentally investigated the buckling of carbon fiber composite cylindrical shells with annular ribs under external pressure. It was found that the distribution and geometry of the ribs have a significant influence on the buckling load and final collapse mode of the material.
ENGINEERING STRUCTURES
(2023)
Article
Engineering, Civil
Kuo Tian, Pingtao Lai, Yu Sun, Wei Sun, Zhizhong Cheng, Bo Wang
Summary: This paper proposes an efficient buckling analysis and optimization method for rotationally periodic stiffened shells accelerated by the Bloch wave method. The method achieves high prediction accuracy in buckling load and remarkable improvement in modeling and analysis efficiency. It successfully captures both local buckling mode and global buckling mode.
ENGINEERING STRUCTURES
(2023)
Article
Mechanics
Emad Sobhani, Amir R. Masoodi, Rossana Dimitri, Francesco Tornabene
Summary: The vibration behavior of porous nano-composite Assembled Paraboloidal-Cylindrical Shell (APCS) structures is evaluated using Graphene Oxide Powder (GOP) nanomaterials to improve the mechanical features of hybrid polymer and metal matrices. The mechanical features of the hybrid matrix structures are determined using the Halpin-Tsai and Rule of Mixture methods. The governing equations of APCSs are determined using the First Shear Deformation Hypothesis (FSDH) and Hamilton's principle, and the frequency responses of the structures are calculated using the eigenvalue strategy.
COMPOSITE STRUCTURES
(2023)
Article
Thermodynamics
Rossana Dimitri, Martina Rinaldi, Marco Trullo, Francesco Tornabene
Summary: This study investigates the fracturing process in geomaterials for characterizing a potential host rock for radioactive waste storage. A semi-circular bending test is modeled using the eXtended Finite Element Method (XFEM) to examine the formation and propagation of cracks in the rock. The study focuses on the effects of notch dimensions and scale on the fracturing response and proposes an analytical formulation for approximating the material's response in terms of load-crack mouth opening displacement.
CONTINUUM MECHANICS AND THERMODYNAMICS
(2023)
Article
Mechanics
Francesco Tornabene, Matteo Viscoti, Rossana Dimitri, Luciano Rosati
Summary: In this study, a general formulation is proposed to consider general boundary conditions for the dynamic analysis of anisotropic laminated doubly-curved shells. A mapping procedure based on Non-Uniform Rational Basis Spline (NURBS) curves is used to describe the distortion of the physical domain. Mode frequencies and shapes are determined using higher-order theories within an Equivalent Single Layer (ESL) framework. The dynamic problem is solved numerically using the Generalized Differential Quadrature (GDQ) method.
COMPOSITE STRUCTURES
(2023)
Article
Mechanics
Mehdi Alimoradzadeh, Francesco Tornabene, Sattar Mohammadi Esfarjani, Rossana Dimitri
Summary: This paper investigates the nonlinear free vibration, superharmonic and subharmonic resonance response of homogeneous Euler-Bernoulli beams resting on nonlinear viscoelastic foundations, considering a moving mass and an abrupt uniform temperature rise. The nonlinear differential equation of motion, derived from the Hamiltonian principle and Finite Strain Theory, is discretized using the Galerkin decomposition method and solved using a multiple time scale method. A comparison between the Finite Strain theory and the Von-Karman approach is discussed, taking into account the effect of temperature rise, linear and nonlinear coefficients of the elastic foundation on the nonlinear vibration history and phase trajectory. Additionally, the sensitivity of the frequency response of the system in superharmonic and subharmonic resonance for different input parameters, such as the location, velocity, and magnitude of the moving load, temperature rise, and elastic foundation, is examined.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2023)
Article
Mathematics, Applied
Rajendran Selvamani, Francesco Tornabene, Dumitru Baleanu
Summary: The present study investigates the two phase local/nonlocal deformation and dynamics of thermo electrical composite nanobeam reinforced with graphene oxide powder (GOP). The results highlight the significant effects of GOP weight fraction, two phase parameter, external electric voltage, and temperature difference on the frequency of the composite beam.
ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK
(2023)
Article
Mechanics
Francesco Tornabene, Matteo Viscoti, Rossana Dimitri
Summary: In this study, an Equivalent Single Layer (ESL) formulation is proposed for the static analysis of doubly curved anisotropic structures of arbitrary geometry and variable stiffness on a Winkler elastic foundation. The proposed formulation provides in-plane and out-of-plane general distributions of linear elastic springs for external constraints along the edges. The use of higher order theories and the Generalized Differential Quadrature (GDQ) method allows for accurate results with reduced computational cost compared to finite element simulations.
COMPOSITE STRUCTURES
(2023)
Article
Thermodynamics
Mohamed-Ouejdi Belarbi, Sattar Jedari Salami, Aman Garg, Ahmed-Amine Daikh, Mohamed-Sid-Ahmed Houari, Rossana Dimitri, Francesco Tornabene
Summary: This paper presents a hyperbolic shear deformation theory for investigating the bending and buckling behavior of functionally graded carbon nanotubes-reinforced composite (FG-CNTRC) beams. The theory satisfies the parabolic variation of shear stress distribution and eliminates the need for correction factors. Finite element analysis is conducted considering different CNT reinforcement distributions and power-law function variations. The proposed model demonstrates accuracy, fast convergence, numerical stability, and validity for both symmetric and non-symmetric FG-CNTRC beams. The study also explores the effects of various material and geometric parameters on the beam's response.
CONTINUUM MECHANICS AND THERMODYNAMICS
(2023)
Article
Mechanics
M. Alimoradzadeh, Habib Heidari, F. Tornabene, R. Dimitri
Summary: This study investigates the nonlinear dynamic behavior of microscale CNTR composite Euler-Bernoulli beams with a non-uniform cross-section using a modified couple stress theory. The nonlinear PDEs of motion are established based on the Von-Karman nonlinear strain-displacement relationship and Hamiltonian principle. The effects of boundary conditions and reinforcement parameters on the nonlinear response of CNTR composite beams are analyzed using numerical simulations, providing insights for further computational investigations.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2023)
Article
Materials Science, Composites
M. Nejati, M. M. Shokrieh, A. Ghasemi Ghalebahman
Summary: A novel method for repairing cracked aluminum sheets using polymer composite patches with embedded prestressed Nitinol shape memory alloy (Ni-Ti SMA) wires is proposed. Elastic-plastic finite element analysis was performed on the repaired aluminum plates with pure mode I and mixed-mode I/II fractures using SMA wires reinforced composite patches (SMA-CP). The performance and efficiency of the repair were evaluated by calculating the peel stress on the adhesive layer between the composite patch and the aluminum plate. The influence of prestressed Ni-Ti SMA wires on the efficiency of the composite patch was examined.
JOURNAL OF COMPOSITE MATERIALS
(2023)
Article
Mechanics
Mohsen Taghizadeh, Masoud Babaei, Rossana Dimitri, Francesco Tornabene
Summary: The buckling behavior of bi-directional functionally graded conical micro-shells subjected to axial loading is investigated in this study, utilizing the modified couple stress theory (MCST) based on the theory of first-order shear deformation. The Ritz technique is employed to solve the governing equations. The micro-shells are constructed using bi-directional functionally graded material, with volume fractions of constituent materials varying continuously along the conical edge directions and thickness according to a predefined composition profile. The model predictions are successfully validated against literature results. The study also examines the influence of various geometrical and mechanical parameters on the buckling performance of conical micro-shells, such as the radius-to-thickness ratio, thickness-to-length scale ratio, length-to-radius ratio, semi-vertex angle, homogenization schemes, and material gradient indexes. It is noteworthy that this investigation presents the first buckling analysis of bi-directional functionally graded truncated conical micro-shells in accordance with the MCST.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Engineering, Mechanical
Souhir Zghal, Najah Joueid, Francesco Tornabene, Rossana Dimitri, Mouldi Chrigui, Fakhreddine Dammak
Summary: This study investigates the time-deflection responses of functionally graded (FG) porous plates and spherical shells under different external pulse excitations using an improved first order shear deformation theory (Im-FSDT) with improved transverse shear deformations. The governing equations for the dynamic transient response are derived using a variational principle and finite element method, and numerically solved using the constant average acceleration Newmark's integration algorithm. The effective material properties are evaluated using a modified power-law distribution with a porosity parameter. The model accuracy is validated and the effects of various parameters are discussed.
JOURNAL OF VIBRATION ENGINEERING & TECHNOLOGIES
(2023)
Article
Chemistry, Multidisciplinary
Zhimin Zhou, Yun Wang, Suying Zhang, Rossana Dimitri, Francesco Tornabene, Kamran Asemi
Summary: The buckling response of functionally graded porous spherical caps reinforced by graphene platelets is studied in this research. The study considers both symmetric and uniform porosity patterns and five different graphene platelet distributions. The elastic properties and mass density of the shells are determined using the Halpin-Tsai model and an extended rule of mixture. The buckling load is obtained using the nonlinear Green strain field and generalized geometric stiffness concept. Parametric investigations reveal the sensitivity of the natural frequencies to various parameters such as porosity coefficients, distributions, polar angles, stiffness coefficients, graphene platelet patterns, and weight fractions. The results show that the maximum buckling load is obtained for the GPL-X distribution, while the minimum load is obtained for GPL-O distribution. The difference between the maximum and minimum critical buckling loads for different porosity distributions is approximately 90%, indicating significant variations. High weight fractions of graphene platelets and porosity coefficients have the highest and lowest effects on the buckling loads, respectively.
Article
Engineering, Multidisciplinary
Francesco Tornabene, Matteo Viscoti, Rossana Dimitri
Summary: This study investigates the dynamic behavior of laminated anisotropic doubly-curved shells with a generalized distribution of the material orientation angle using higher order theories. The equivalent single layer methodology is used to develop the structural problem and establish a unified approach for evaluating displacement field variables with higher order theories. A generalized three-dimensional distribution of the material orientation angle is associated with each layer of the stacking sequence, accounting for in-plane bivariate power distribution and out-of-plane symmetric and unsymmetric profiles described with polynomial and non-polynomial analytical expressions. The fundamental equations are derived using the Hamiltonian Principle and numerically solved using the Generalized Differential Quadrature method.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2023)
Article
Engineering, Multidisciplinary
Francesco Tornabene, Matteo Viscoti, Rossana Dimitri
Summary: This manuscript investigates the dynamic properties of doubly-curved shell structures laminated with innovative materials using the Generalized Differential Quadrature (GDQ) method. The displacement field variable follows the Equivalent Single Layer (ESL) approach, and the geometrical description of the structures is distorted by generalized isogeometric blending functions. Through non-uniform discrete computational grid, the fundamental equations derived from the Hamiltonian principle are solved in strong form. Parametric investigations show the influence of material property variation on the modal response of the structures.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
