Kecheng Li, Jianlong Qu, Jinqiang Tan, Zhanjun Wu, Xinsheng Xu^*

Structural Durability & Health Monitoring, Vol.15, No.1, pp. 53-67, 2021, DOI:10.32604/sdhm.2021.014559

Abstract In this paper, the local buckling of cylindrical long shells is discussed under axial pulse loads in a Hamiltonian system. Using this system, critical loads and modes of buckling of shells are reduced to symplectic eigenvalues and eigensolutions respectively. By the symplectic method, the solution of the local buckling of shells can be employed to the expansion series of symplectic eigensolutions in this system. As a result, relationships between critical buckling loads and other factors, such as length of pulse load, thickness of shells and circumferential orders, have been achieved. At the same time, symmetric and unsymmetric buckling modes have… More >

Jiachen Guo^1,2, Yunfei Xu², Zhenyu Jiang^1,*, Xiaoyi Liu², Yang Cai^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.2, pp. 611-623, 2020, DOI:10.32604/cmes.2020.011148

Abstract Both of Buckling and post-buckling are fundamental problems of geometric nonlinearity in solid mechanics. With the rapid development of nanotechnology in recent years, buckling behaviors in nanobeams receive more attention due to its applications in sensors, actuators, transistors, probes, and resonators in nanoelectromechanical systems (NEMS) and biotechnology. In this work, buckling and post-buckling of copper nanobeam under uniaxial compression are investigated with theoretical analysis and atomistic simulations. Different cross sections are explored for the consideration of surface effects. To avoid complicated high order buckling modes, a stressbased simplified model is proposed to analyze the critical strain for buckling, maximum deflection,… More >

L. Nobile¹, C. Carloni¹

Structural Durability & Health Monitoring, Vol.2, No.2, pp. 83-90, 2006, DOI:10.3970/sdhm.2006.002.083

Abstract The analysis of buckling of elastic columns is one of the first problem in structural engineering that was historically solved. Critical loads of perfect columns with various end restrains have been derived. Nevertheless, the perfect column is an idealized model. In reality, unavoidable imperfections should be considered. Solutions for transversal disturbing load, crookedness or load eccentricity have been proposed. Another frequent imperfection to be taken into account is the weakness at an interior location due to a partial edge crack. In this paper the influence of this type of imperfection on the critical load is analyzed. The case of the… More >

P.M. Baiz¹, M.H. Aliabadi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.13, No.1, pp. 19-34, 2006, DOI:10.3970/cmes.2006.013.019

Abstract In this paper the linear buckling problem of elastic shallow shells by a shear deformable shell theory is presented. The boundary domain integral equations are obtained by coupling two dimensional plane stress elasticity with boundary element formulation of Reissner plate bending. The buckling problem is formulated as a standard eigenvalue problem, in order to obtain directly critical loads and buckling modes as part of the solution. The boundary is discretised into quadratic isoparametric elements while in the domain quadratic quadrilateral cells are used. Several examples of cylindrical shallow shells (curved plates) with different dimensions and boundary conditions are analysed. The… More >

J. Li¹, Z.H. Xiang¹, M.D. Xue¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.2, No.1, pp. 7-12, 2007, DOI:10.3970/icces.2007.002.007

Abstract This paper presents a finite element scheme to analyze the buckling behavior of composite shells subjected to thermal and mechanical loads. Firstly, a kind of multi-layered composite shell element with relative degrees-of-freedom is adopted to model laminated composite shells. Then the corresponding temperature element is developed so that the mechanical analysis and the thermal analysis share a common mesh. Moreover, a new criterion of critical heat flux is proposed in stead of the traditional criterion of critical temperature. Finally, the advantage of the proposed scheme is illustrated by calculating the stable region of thermal-mechanical loads for a honeycomb sandwich composite… More >

J. Li, Z. H. Xiang, M. D. Xue¹

CMC-Computers, Materials & Continua, Vol.2, No.2, pp. 139-150, 2005, DOI:10.3970/cmc.2005.002.139

Abstract This paper investigates the buckling response of honeycomb sandwich composite shells with cutouts under axial compression. The Wilson's incompatible solid Finite Element (FE) is used around cutouts to obtain the detail stress distribution there. While to reduce the computational expense, a special multilayered relative degrees-of-freedom (DOF) shell FE is used to model the regions far from the cutouts. The efficiency and accuracy of this modeling scheme are illustrated by two benchmarks. Then parametric studies are carried out to reveal how the buckling response is influenced by the area, the shape and the orientation of cutouts. More >

Farzad Ebrahimi^1,2, Erfan Salari¹

CMES-Computer Modeling in Engineering & Sciences, Vol.105, No.2, pp. 151-181, 2015, DOI:10.3970/cmes.2015.105.151

Abstract In this paper, a semi-analytical method is presented for free vibration and buckling analysis of functionally graded (FG) size-dependent nanobeams based on the physical neutral axis position. It is the first time that a semi-analytical differential transform method (DTM) solution is developed for the FG nanobeams vibration and buckling analysis. Material properties of FG nanobeam are supposed to vary continuously along the thickness according to the power-law form. The physical neutral axis position for mentioned FG nanobeams is determined. The small scale effect is taken into consideration based on nonlocal elasticity theory of Eringen. The nonlocal equations of motion are… More >

Guangyao Li¹, Shuaiping Guo¹, Jianming Zhang^1,2, Baiping Fei¹, Yuan Li¹

CMES-Computer Modeling in Engineering & Sciences, Vol.98, No.5, pp. 487-508, 2014, DOI:10.3970/cmes.2014.098.487

Abstract In this paper, we will propose a new concept, namely the Complete Solid Buckling Analysis, in which the deformation assumptions for rods, beams and plates are all discarded, and the entire structure, including all its local smallsized features, is modeled as a three-dimensional (3D) solid according to its real shape and dimensions. Firstly, we derive a new control equation, in which physical variables in three directions are considered. Then, an equivalent Boundary Integral Equation (BIE) is derived from the control equation. In the numerical implementation, the Boundary Face Method is employed, by which analyses can be performed directly on the… More >

Chih-Ping Wu^1,2, Ruei-Yong Jiang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.97, No.3, pp. 239-279, 2014, DOI:10.3970/cmes.2014.097.239

Abstract A state space differential reproducing kernel (DRK) method is developed for the three-dimensional (3D) buckling analysis of simply-supported, carbon nanotube-reinforced composite (CNTRC) circular hollow cylinders and laminated composite ones under axial compression. The single-walled carbon nanotubes (CNTs) and polymer are used as the reinforcements and matrix, respectively, to constitute the CNTRC cylinder. Three different distributions of CNTs varying in the thickness direction are considered (i.e., the uniform distribution and functionally graded rhombus-, and X-type ones), and the through-thickness distributions of effective material properties of the cylinder are determined using the rule of mixtures. The 3D linear buckling theory is used,… More >

Hao Zuo^1,2, Zhi-Bo Yang^1,2,3, Xue-Feng Chen^1,2, Yong Xie⁴, Xing-Wu Zhang^1,2, Yue Liu⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.100, No.6, pp. 477-506, 2014, DOI:10.3970/cmes.2014.100.477

Abstract The application of B-spline wavelet on the interval (BSWI) finite element method for static, free vibration and buckling analysis in functionally graded (FG) beam is presented in this paper. The functionally graded material (FGM) is a new type of heterogeneous composite material with material properties varying continuously throughout the thickness direction according to power law form in terms of volume fraction of material constituents. Different from polynomial interpolation used in traditional finite element method, the scaling functions of BSWI are employed to form the shape functions and construct wavelet-based elements. Timoshenko beam theory and Hamilton’s principle are adopted to formulate… More >