Geometric modelling of kink banding in laminated structures

Journal of Materials Science, 2012

This study investigates and reviews approaches to modelling laminated composite plates. It explores theories that have been proposed and developed and assesses their suitability and functionality. The particular focus in this study has been on normal stresses and the throughthickness distributions of transverse shear. These are important for composite plates as stress-induced failures can occur in three different ways. Therefore, it is essential to understand and calculate transverse shear and normal stress through the thickness of the plate accurately. In this study, previous laminated composite plate theories are categorised and reviewed in a general sense, i.e. not problem specific, and the advantages and disadvantages of each model are discussed. This research mainly focuses on how accurate and efficient the models can predict the transverse shear. It starts with displacement-based theories from very basic models such as Classical laminate plate theory to more complicated and higher-order shear deformation theory. Models are furthermore categorised by how the models consider the overall laminate. In this article, the theories are divided into two parts: Single layer theory, where the whole plate is considered as one layer; and Layerwise theory, where each layer is treated separately. The models based on zigzag and Discrete Theories are then reviewed, and finally the mixed (hybrid) plate theories are studied.

Computers & Structures, 2013

Strain based finite element Composite beam Geometrical and material non-linearity Slip between layers a b s t r a c t

International Journal for Research in Applied Science and Engineering Technology, 2023

This paper presents a numerical method using ANSYS to estimate the buckling loads of composite plates. Our approach employs an element based on FSDT that considers out-of-plane shear deformation. We used an Eight node SHELL281 element that is well-suited for analyzing plate and shell structures. The ANSYS results for buckling loads of isotropic and orthotropic layered laminates are in good agreement with other theories from the literature. In this study, we investigated uniaxial and biaxial buckling of the plates and also considered the degree of orthotropy to study its impact on the plates' buckling. I. INTRODUCTION Researchers have extensively studied the load-carrying capacity of fiber-reinforced composites in the form of relatively thick plates, considering various loading and boundary conditions to prevent buckling. The following is a list of researchers who have investigated the elastic buckling of laminated composite plates. Jones [1] investigated the behavior of composite laminated plates, including both macro and micromechanical behavior, and analyzed the plates. Reddy [2] presented different shear deformation theories for composite laminated plates and their finite element formulation, while also analyzing them. Kaw [3] introduced composite materials and analyzed their macro and micromechanical behavior, including failure, analysis, and design of laminates. Gibson [4] studied fiber-reinforced composite laminate, analyzing hygrothermal effects, interlaminate stresses, laminate strength analysis, deflection and buckling of laminates, and selection of laminate design. Ferreira et al. [5] used radial basis function to analyze the static deformations of composite beams and plates. Reddy and Phan [6] studied higher-order shear deformation theory and its application to stability and vibration of composite laminated plates. Kant and Swaminathan [7] presented an analytical solution for composite plates, including the effect of transverse shear deformation, transverse normal strain/stress, and a nonlinear variation of in-plane displacements with respect to the thickness coordinates. Noor et al. [8] used numerical simulations to study the buckling and post-buckling responses and failure initiation of flat, unstiffened composite panels. Reddy and Barbero [9] developed a plate bending element based on the generalized laminate plate theory and presented a method for computing interlaminar stresses. Hsuan and Horng [10] used a sequential linear programming method to maximize the buckling resistance of symmetrically laminated plates with a given material system and subjected to uniaxial compression. Matsunaga [11] analyzed the natural frequencies and buckling stresses of cross-ply laminated composite plates, considering the effects of shear deformation, thickness change, and rotatory inertia. Bert and Devarakonda [12] presented a solution for the buckling of a rectangular plate subjected to a half-sine load distribution on two opposite sides. Akavci et al. [13] studied laminated plates on an elastic foundation, analyzing the bending deflections of symmetric cross-ply laminates. Panda and Ramchandra [14] studied the buckling and post-buckling behavior of simply supported composite plates, including the effect of shear deformation on the buckling load. Khdeir [15] developed an exact solution to the buckling of antisymmetric angle-ply laminated plates, and Shukla et al. [16] estimated critical or buckling loads of laminated composite rectangular plates under in-plane loading. The study by Nemeth and Nemith and Weaver [17] presented non-dimensional parameters and equations that govern the buckling behavior of rectangular symmetrically laminated plates. These equations can be applied to plates made of various structural materials in a general and comprehensive way to represent their buckling resistance. York [18] focused on the benchmark configuration of fully extensionally isotropic laminated plates with matching elastic properties in both extension and bending, as well as some special cases. Ren and Tong [19] reviewed previous research on the elastic buckling of rectangular plates with different boundary conditions and simulated the realistic load and restraining conditions of web plates in I-girders. They analyzed the buckling load of a large number of models under patch load using ANSYS and proposed formulas to predict the elastic buckling coefficients of the webs in I-girders. Their formulas accurately considered the rotational restraints provided by the flanges on the web plates.

Central European Journal of Engineering, 2011

Page 1. Cent. Eur. J. Eng. DOI: 10.2478/s13531-011-0005-x Central European Journal of Engineering A literature review on computational models for laminated composite and sandwich panels Review Article Ireneusz Kreja∗ ...

Composite Structures, 2020

Based on fundamental equations of the elasticity theory, a novel unified beam model is developed for laminated composite beams. In this model, the displacement field is selected in a unified form which can be recovered to that of existing shear deformation beam theories available in the literature. Based on Lagrange's equations, the governing equations of the present theory are derived. They are then solved for deflections, stresses, natural frequencies and critical buckling loads of composite beams under different boundary conditions and lay-ups by using the Ritz approach with novel hybrid trigonometric functions. Various examples are also presented to verify the accuracy and generalization of the present theory, as well as investigate the influences of fibre angle on the behaviour of composite beams under different boundary conditions and lay-ups.