Dynamics of multilayer structures
Abstract
~ The dynamic response of composite and sandwich structures has been analyzed using two types off theories: equivalent single layer (ESL) or multilayer theories. Each one has many variants; a comprehensive assessment of current theories has shown that most higher order approaches yield very similar results.~ In this project we will evaluate the ability of existing theories to provide accurate stress predictions. Transverse stresses are of particular interest since they are needed to predict delamination~s and intra-ply cracking under impact, blast, and other dynamic loading~ Will develop a hierarchical approach to develop beam and plate theories for improved dynamic behavior.~ Existing theories will be compared on the basis of their kinematic assumptions. Preliminary results on 12 very different approaches indicated that, when expanded in a Taylor series up to 3rd order, these are virtually identical. Very small differences result in minute differences in predicted deflections, stresses and natural frequencies. This work will be extended to cover all major approaches.~ The dynamic behavior of the various theories will be assessed by comparing the dispersion curves for harmonic wave propagation between theories and by comparison with 3D-elasticity results.~ The development of refined models depends on the choice of an appropriate displacement field. A systematic examination identified terms that affect in-plane deformations, bending deformations, and transverse deformations. This will be used to develop a systematic approach for developing efficient models.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Nov 23, 2016
- Source ID
- N000141613192
Entities
People
- Serge Abrate
Organizations
- Office of Naval Research
- Southern Illinois University
- United States Navy