Title page for ETD etd-02152008-150145


Type of Document Dissertation
Author Zhou, Feng
Author's Email Address zhouf@vt.edu
URN etd-02152008-150145
Title Ultimate Strength of Clamped Steel-Elastomer Sandwich Panels under Combined In-plane Compression and Lateral Pressure
Degree PhD
Department Aerospace and Ocean Engineering
Advisory Committee
Advisor Name Title
Hughes, Owen F. Committee Chair
Brown, Alan J. Committee Member
Kapania, Rakesh K. Committee Member
Neu, Wayne L. Committee Member
Plaut, Raymond H. Committee Member
Keywords
  • Lateral Pressure
  • In-plane Compression
  • Ultimate Strength
  • Steel-Elastomer
  • Sandwich Panels
Date of Defense 2008-02-04
Availability unrestricted
Abstract
An efficient interaction formula and a semi-analytical method are developed for calculating the ultimate strength of steel-elastomer sandwich panels under combined in-plane compression and lateral pressure.

By using the Galerkin method and extending the semi-analytical method to clamped sandwich panels, the governing equations of sandwich panels have been solved by the Galerkin method. The material nonlinearity is treated by iteration and a three-dimensional mesh. For the load case of pure lateral pressure, the ultimate strength from the semi-analytical method is similar to that from hinge line theory and finite element analysis (FEA). However, the semi-analytical method requires about as much computation as FEA, and it is therefore not suitable for design.

Finite element modeling and nonlinear analysis are performed to calculate the ultimate strength of sandwich panels under combined load. The results agree with experimental results. This verifies the accuracy of the current finite element model. The verified finite element model is used to obtain the results for a large set of sandwich panels with various dimensions and load combinations. The FEA results for pure lateral pressure load cases are used to derive a correction factor for the hinge line formula. Statistical analysis confirms that the generalized hinge line formula gives accurate values of ultimate strength of sandwich panels under pure lateral pressure.

Except for the pressure-only FEA data points, the other FEA data points are corrected so as not to count the in-plane load carried by the elastomer core. Based on the corrected FEA data points, a general expression is developed for an interaction equation. The resulting equation has a bias of -0.003 and a standard deviation of 0.029. Since the radius of the interaction curve is close to 1, this standard deviation is of the order of 3%, which shows that the ultimate strength given by the equation is very close to the FEA results. The interaction equation is so simple that the ultimate strength of clamped sandwich panels under combined in-plane compression and lateral pressure can be easily calculated.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  FENG_ZHOU_DISSERTATION.pdf 2.73 Mb 00:12:39 00:06:30 00:05:41 00:02:50 00:00:14

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.