ISSN 打印: 1543-1649
ISSN 在线: 1940-4352

# 国际多尺度计算工程期刊

DOI: 10.1615/IntJMultCompEng.2012002511
pages 249-259

## BUCKLING ANALYSIS OF RECTANGULAR FLEXURAL MICROPLATES USING HIGHER CONTINUITY P-VERSION FINITE-ELEMENT METHOD

International Center for Science and High Technology and Environmental Sciences, Kerman, Iran
H. Farahmand
Department of Mechanical Engineering, Islamic Azad University of Kerman Branch, Kerman, Iran
Young Researchers Club, Kerman branch, Islamic Azad University, Kerman, Iran

### ABSTRACT

In this article, elastic buckling of rectangular flexural micro plates (FMPs), using a higher continuity p-version finite-element framework based on Galerkin formulation, is investigated. The invariant form of governing equation for microplates with nonlocal effects based on "modified couple stress theory" is extended for buckling analysis of FMPs by considering the strain gradient effects, for which the constitutive equation of the strain gradient model contains only one constant. The Galerkin weak form of the governing equation is derived and subsequently solved for a variety of boundary conditions, using higher continuity p finite elements, to extract critical buckling loads. Here the computational procedure is verified by comparing the results to those of the classical theory and microplate studies reported in literature. Investigations indicate that the length scale parameter affects the computed flexural stiffness of a plate directly proportional to the value of gradient coefficient considered for that plate. Hence there is a strong influence of length scale parameter on the value of the buckling load. Depending on boundary conditions and the length scale parameter value, the classical plate model severely underestimates (up to 90%) the buckling load of microplates. Therefore it is concluded that the classical plate theory cannot be used to predict structural response when length scale effects are present.

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