Nonlinear analysis of composite laminates using a generalized laminated plate theory

AIAA Journal ◽  
1990 ◽  
Vol 28 (11) ◽  
pp. 1987-1994 ◽  
Author(s):  
E. J. Barbero ◽  
J. N. Reddy
Keyword(s):  
Nonlinear Analysis ◽  
Composite Laminates ◽  
Plate Theory ◽  
Laminated Plate

Effects of Feedrate and Chisel Edge on Delamination in Composites Drilling

1993 ◽  
Vol 115 (4) ◽  
pp. 398-405 ◽  
Author(s):  
S. Jain ◽  
D. C. H. Yang
Keyword(s):  
Composite Laminates ◽  
Thrust Force ◽  
Plate Theory ◽  
Tool Geometry ◽  
Laminated Plate ◽  
Elliptical Plate ◽  
Time Optimal ◽  
Critical Thrust Force ◽  
Clamped Edges ◽  
Central Load

Delamination accompanied with the drilling of composite laminates has been recognized as a major problem. An analytical model is established to predict critical thrust force and critical feedrate at which the delamination crack begins to propagate. For unidirectional composites, the delamination zone is modeled as an elliptical plate, with clamped edges and subjected to a central load. Based on fracture mechanics, laminated plate theory and cutting mechanics, expressions are developed for critical thrusts and critical feedrates at which delamination is initiated at different ply locations. This model has been verified by experiments. A variable feedrate strategy is formulated based on this model, which avoids delamination while drilling in a time-optimal fashion. In addition, the need to modify tool geometry to avoid delamination is highlighted. Chisel edge width has been identified as an important factor contributing to the thrust force and hence delamination.

Nonlinear Oscillations of a Composite Laminated Plate with Parametrically and Externally Excitations

2013 ◽  
Vol 699 ◽  
pp. 641-644
Author(s):  
Xiao Li Bian ◽  
Shuang Bao Li
Keyword(s):  
Thin Plate ◽  
Nonlinear Oscillations ◽  
Plate Theory ◽  
Laminated Plate ◽  
Rectangular Thin Plate ◽  
Third Order ◽  
Composite Laminated Plate ◽  
Strain Relationship ◽  
Relationship Of ◽  
Equations Of Motions

Nonlinear oscillations of a simply-supported symmetric cross-ply composite laminated rectangular thin plate are investigated in this paper. The rectangular thin plate is subjected to the transversal and in-plane excitations. Based on the Reddy’s third-order shear deformation plate theory and the stress-strain relationship of the composite laminated plate, a two-degree-of-freedom non-autonomous nonlinear system governing equations of motions for the composite laminated rectangular thin plate is derived by using the Galerkin’s method. Numerical simulations illustrate that there exist complex nonlinear oscillations for composite laminated rectangular thin plate.

scholarly journals Parametric structural modelling of fish bone active camber morphing aerofoils

2018 ◽  
Vol 29 (9) ◽  
pp. 2008-2026 ◽  
Author(s):  
Andres E Rivero ◽  
Paul M Weaver ◽  
Jonathan E Cooper ◽  
Benjamin KS Woods
Keyword(s):  
Analytical Model ◽  
Composite Laminates ◽  
Plate Theory ◽  
Ritz Method ◽  
Linear Equations ◽  
Variable Stiffness ◽  
Automated Analysis ◽  
Fish Bone ◽  
Two Dimensional ◽  
Wide Range

Camber morphing aerofoils have the potential to significantly improve the efficiency of fixed and rotary wing aircraft by providing significant lift control authority to a wing, at a lower drag penalty than traditional plain flaps. A rapid, mesh-independent and two-dimensional analytical model of the fish bone active camber concept is presented. Existing structural models of this concept are one-dimensional and isotropic and therefore unable to capture either material anisotropy or spanwise variations in loading/deformation. The proposed model addresses these shortcomings by being able to analyse composite laminates and solve for static two-dimensional displacement fields. Kirchhoff–Love plate theory, along with the Rayleigh–Ritz method, are used to capture the complex and variable stiffness nature of the fish bone active camber concept in a single system of linear equations. Results show errors between 0.5% and 8% for static deflections under representative uniform pressure loadings and applied actuation moments (except when transverse shear exists), compared to finite element method. The robustness, mesh-independence and analytical nature of this model, combined with a modular, parameter-driven geometry definition, facilitate a fast and automated analysis of a wide range of fish bone active camber concept configurations. This analytical model is therefore a powerful tool for use in trade studies, fluid–structure interaction and design optimisation.

scholarly journals Optical Properties and Mechanical Modeling of Acetylated Transparent Wood Composite Laminates

Materials ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2256
Author(s):  
Kyle E. O. Foster ◽  
Kristen M. Hess ◽  
Garret M. Miyake ◽  
Wil V. Srubar
Keyword(s):  
Mechanical Properties ◽  
Composite Laminates ◽  
Plate Theory ◽  
Tensile Modulus ◽  
Fiber Direction ◽  
New Class ◽  
Polymer Resin ◽  
Optical Responses ◽  
Optical And Mechanical Properties ◽  
Wood Template

Transparent wood composites (TWCs) are a new class of light-transmitting wood-based materials composed of a delignified wood template that is infiltrated with a refractive- index-matched polymer resin. Recent research has focused primarily on the fabrication and characterization of single-ply TWCs. However, multi-ply composite laminates are of interest due to the mechanical advantages they impart compared to the single ply. In this work, 1- and 2-ply [0°/90°] TWC laminates were fabricated using a delignified wood template (C) and an acetylated delignified wood template (AC). The optical and mechanical properties of resultant C and AC TWC laminates were determined using ultraviolet-visible spectroscopy (UV-Vis) and tensile testing (5× replicates), respectively. In addition, the ability of classical lamination plate theory and simple rule of mixtures to predict multi-ply tensile modulus and strength, respectively, from ply-level mechanical properties were investigated and are reported herein. Experimental results highlight tradeoffs that exist between the mechanical and optical responses of both unmodified and chemically modified TWCs. Template acetylation reduced the stiffness and strength in the 0° fiber direction by 2.4 GPa and 58.9 MPa, respectively, compared to the unmodified samples. At high wavelengths of light (>515 nm), AC samples exhibited higher transmittance than the C samples. Above 687 nm, the 2-ply AC sample exhibited a higher transmittance than the 1-ply C sample, indicating that thickness-dependent optical constraints can be overcome with improved interfacial interactions. Finally, both predictive models were successful in predicting the elastic modulus and tensile strength response for the 2-ply C and AC samples.

A Composite Plate Theory for Arbitrary Laminate Configurations

1987 ◽  
Vol 54 (1) ◽  
pp. 181-189 ◽  
Author(s):  
A. Toledano ◽  
H. Murakami
Keyword(s):  
Composite Plate ◽  
Plate Theory ◽  
Piecewise Linear ◽  
Present Theory ◽  
Laminated Plates ◽  
Stress Distributions ◽  
Laminated Plate ◽  
Individual Layer ◽  
Mixed Variational Principle ◽  
Shear Deformable

In order to improve the accuracy of in-plane responses of shear deformable composite plate theories, a new laminated plate theory was developed for arbitrary laminate configurations based upon Reissner’s (1984) new mixed variational principle. To this end, across each individual layer, piecewise linear continuous displacements and quadratic transverse shear stress distributions were assumed. The accuracy of the present theory was examined by applying it to the cylindrical bending problem of laminated plates which had been solved exactly by Pagano (1969). A comparison with the exact solutions obtained for symmetric, antisymmetric, and arbitrary laminates indicates that the present theory accurately estimates in-plane responses, even for small span-to-thickness ratios.

Coupling of Continuum Damage Mechanics with De-Cohesive Element for Delamination Analysis in Laminated Composites

2010 ◽  
Vol 123-125 ◽  
pp. 527-530
Author(s):  
Hossein Hosseini-Toudeshky ◽  
Bijan Mohammadi
Keyword(s):  
Mesh Generation ◽  
Composite Laminates ◽  
Damage Mechanics ◽  
Plate Theory ◽  
Continuum Damage Mechanics ◽  
Constitutive Law ◽  
Interface Element ◽  
Continuum Damage ◽  
Interface Modeling ◽  
Edge Delamination

To predict the progressive damages including the large delamination growth in composite laminates, a new interface de-cohesive constitutive law is developed which is compatible with 3D continuum damage mechanics (CDM). To avoid the difficulties of 3D mesh generation and 3D interface modeling between the layers, the interface element is implemented in the Reddy’s full layer-wise plate theory. An angle-ply laminate is analyzed to evaluate the developed CDM+Interface procedure in edge delamination initiation and evolution at final stage of CDM damage progress.

Probabilistic Optimum Design of Composite Laminates

1998 ◽  
Vol 32 (1) ◽  
pp. 68-82 ◽  
Author(s):  
S. Mahadevan ◽  
X. Liu
Keyword(s):  
Objective Function ◽  
Optimum Design ◽  
Composite Laminates ◽  
Plate Theory ◽  
Limit State ◽  
Strength Criterion ◽  
System Level ◽  
State Function ◽  
Practical Procedure ◽  
Reliability Method

This paper proposes a procedure for the optimum design of composite laminates under probabilistic considerations. The problem is formulated to consider the minimization of laminate weight as the objective function and the reliability requirements as the constraints. Both system-level and element-level reliabilities are considered. The first-order reliability method (FORM) is used to estimate the reliability of each ply group, and system reliability is computed based on series or parallel system assumptions. The Tsai-Wu strength criterion is adopted to derive the limit state function of individual ply groups in the laminate. The gradient and sensitivity information of the objective function and the constraints with respect to the design variables are obtained by using sensitivity analysis based on the composite plate theory. Thus the proposed procedure brings together modern concepts of reliability analysis, composite laminate behavior and nonlinear optimization to develop a rational and practical procedure for the optimum design of composite laminates. Numerical examples are presented to demonstrate the effectiveness of the proposed method.

Vibration Analysis of Rectangular Functionally Graded Plate Bonded With PZT5 Sensor/Actuator

2010 ◽  
Author(s):  
M. H. Kargarnovin ◽  
N. S. Viliani
Keyword(s):  
Volume Fraction ◽  
Plate Theory ◽  
Equations Of Motion ◽  
Equation Of Motion ◽  
Functionally Graded ◽  
Bottom Surface ◽  
Feedback Gain ◽  
Laminated Plate ◽  
Functionally Graded Plate ◽  
Sensor Actuator

The vibration of FG plate embedded with PZT5 rectangular patches on the top and/or the bottom surface(s) as actuators/sensors is investigated. Based on the classical laminated plate theory, the governing differential equations of motion are derived under a variable electric charge. The equation of motion for PZT5 patch is obtained and solved. The effect of feedback gain and FGM volume fraction exponent on the plate frequency and its deflection are studied. It is noticed that increasing the feedback gain leads to the reduction of frequency and displacement. Moreover, by increasing the value of the FGM volume fraction exponent the resonant frequency decreases.

Effects of Delaminations on Vibration Characteristic for HT3/5224 Carbon Fiber Reinforced Laminated Plate

2013 ◽  
Vol 652-654 ◽  
pp. 52-55
Author(s):  
Wei Liang ◽  
Yu Feng Liu ◽  
Nai Bin Yang
Keyword(s):  
Carbon Fiber ◽  
Fundamental Frequency ◽  
Composite Laminates ◽  
Composite Structures ◽  
Great Influence ◽  
Vibration Characteristic ◽  
Laminated Plate ◽  
Fiber Reinforced ◽  
Carbon Fiber Reinforced ◽  
Kirchhoff Theory

Delaminating of composite is one of keys for composite structures. An energy method was used to analyze the fundamental frequency of HT3/5224 carbon fiber reinforced laminated plate in this paper. Different delaminated situations are considered in analysis on vibration of composite based on Kirchhoff theory. The results show that delaminations have a great influence on the fundamental frequency of laminated plate. The discussion shows inner delaminations have more influence on composite laminates than surface delaminations. Different kinds of delaminations can interact each other and the interaction can increase the influence on frequency.

Sign in / Sign up

Export Citation Format

Share Document