In this work an attempt has been made to develop theories for finite element static and dynamic stress analysis tailored for use with composite layered plates and shells in this way it was hoped to provide accurate values of the stresses particularly transverse shear stresses through the thickness, and to perform accurate natural frequency analysis by including non-linear effects such as centrifugal stiffening. Initial derivations were based upon first order facet shell element analysis and first order curved shell element analysis. Subsequently, derivations were produced for higher order element analysis. A programming package has been developed based upon the above derivations, and containing a banded solver as well as a frontal solver, capable of analysing structures build up from uniform or variable thickness layers and with a multiple number of layers having constant or variable dimension. Results obtained with the aid of the present package have been compared with results derived from experimental work as well as with results derived from available analytical solutions. Investigations have been carried out for existing compressor blades, made of isotropic material and layered composite material, respectively. The results obtained from the package have been compared with available experimental results produced by RR or carried out at Cranfield. It has been shown that the above mentioned derivations produce comparable results and the package has proved to be reliable and accurate.

This report presents the results of an investigation into the formulation and application of assumed-stress hybrid finite-elements for bending of multilayer laminated plates and shells. Two families of hybrid-stress-based multilayer plate elements are considered; these elements are denoted as thick plate and moderately-thick plate elements. In the development of the thick plate elements, transverse shear deformation effects are included by allowing lines normal to the plate midsurface in the undeformed state to be piecewise linear from layer to layer in the deformed state. Transverse shear deformation effects are included in an average sense in the moderately-thick plate element family by assuming that straight lines normal to the plate midsurface prior to deformation remain straight but not necessarily normal to the plate midsurface after deformation. Comparison of the results obtained by using the thick plate and moderately-thick plate elements with independent analytical results shows that the moderately-thick plate elements are more efficient and practical for the analysis of multilayer structures having a large number of elastically dissimilar layers.

Thermal Stress Analysis of Composite Beams, Plates and Shells: Computational Modelling and Applications presents classic and advanced thermal stress topics in a cutting-edge review of this critical area, tackling subjects that have little coverage in existing resources. It includes discussions of complex problems, such as multi-layered cases using modern advanced computational and vibrational methods. Authors Carrera and Fazzolari begin with a review of the fundamentals of thermoelasticity and thermal stress analysis relating to advanced structures and the basic mechanics of beams, plates, and shells, making the book a self-contained reference. More challenging topics are then addressed, including anisotropic thermal stress structures, static and dynamic responses of coupled and uncoupled thermoelastic problems, thermal buckling, and post-buckling behavior of thermally loaded structures, and thermal effects on panel flutter phenomena, amongst others. - Provides an overview of critical thermal stress theory and its relation to beams, plates, and shells, from classical concepts to the latest advanced theories - Appeals to those studying thermoelasticity, thermoelastics, stress analysis, multilayered structures, computational methods, buckling, static response, and dynamic response - Includes the authors' unified formulation (UF) theory, along with cutting-edge topics that receive little coverage in other references - Covers metallic and composite structures, including a complete analysis and sample problems of layered structures, considering both mesh and meshless methods - Presents a valuable resource for those working on thermal stress problems in mechanical, civil, and aerospace engineering settings

Over the past decade or so much has been written on the various attempts to produce efficient, accurate and reliable Mindlin plate finite elements. In the late sixties, a degenerated, Mindlin-type, curved shell element was developed and subsequently many improvements in such elements have been made. Reliability and efficiency in use has always been a major objective. Degenerated shell elements have enjoyed widespread popularity despite certain potential defects, including shear and membrane lock ing behaviour and spurious mechanisms. After introducing the basic foundations of Mindlin-type elements, this book describes these defects and also gives the reasons for their occurrence. Furthermore, the author proposes an approach to overcome these defects. A series of linear benchmark tests are proposed to illustrate the performance of the assumed strain element formulations. The formula tions and applications for material non-linearity are also presented. Both isotropic and anisotropic material models are included together with the results for both static and transient dynamic analyses. Two associated programs are fully documented and provided on floppy discs with test examples. Source codes for the two associated programs are provided: one is for static analysis and the other for dynamic analysis, and the programs can be compiled and run on either a mini or mainframe coniputer via a terminal. The author hopes that this book may provide further impetus in the important research area of plate and shell element technology.

This thesis introduces new conforming and non-conforming finite elements for the static and dynamic analysis of rotating composite layered plates and shells. The elements consider parabolic distributions of transverse shear stresses, and based on Lagrangian and Hermitian shape functions. They can deal with variable thickness distributions as well as uniform distributions, and they are fully capable to deal with rotating plate and shell structures, i. e. centrifugal stiffening and Coriolis force effects are considered. Natural frequency analysis, forced vibration analysis, and flutter analysis of composite layered plate and shell structures, employing those elements, have been investigated. A computer programming package based on the developed theory was designed, and it is machine independent and user friendly. A modular approach was adopted in the package structure to allow any further development to be considered. Efficient frontal solvers were adopted in the package for different types of analysis. The developed package has been successfully validated on a main frame computer (VAX), Unix workstations, and personal computers. Several case studies were investigated and the results obtained were compared with corresponding, published theoretical and/or experimental work. The package has proved to be a very useful tool for the design optimization of composite layered plates and shells by means of using different fibre angles for different layers so as to achieve the required strength and/or stiffness.

The vibrational characteristics and mechanical properties of shell structures are discussed. The subjects presented are: (1) fundamental equations of thin shell theory, (2) characteristics of thin circular cylindrical shells, (3) complicating effects in circular cylindrical shells, (4) noncircular cylindrical shell properties, (5) characteristics of spherical shells, and (6) solution of three-dimensional equations of motion for cylinders.