You are here
Local buckling and debond propagation in sandwich columns and panels
- Date Issued:
- 2005
- Summary:
- The local buckling failure mechanism and subsequent debond propagation in sandwich columns and panels with composite face sheets containing a face-to-core debond is experimentally, analytically, and numerically analyzed. The experimental investigation is based on a comprehensive test program to examine local buckling failure and fracture toughness of sandwich specimens consisting of glass/epoxy face sheets over various density PVC foams and a balsa wood core. Elastic foundation and finite element models are developed for prediction of the local buckling load of sandwich columns and panels containing an implanted debond at the face/core interface. Nonlinear finite element analysis was conducted to investigate debond propagation in the post-buckling region. Overall, model predictions were in agreement with experimental results. The buckling load was found to decrease with reduced face sheet stiffness, reduced core modulus, and increased debond length. Sandwich panels with circular debonds were more resistant to local buckling than those with square debonds of the same characteristic size. Circular debonds of 50 mm diameter and square debonds of 45 mm side length established the threshold for local buckling failure. Nonlinear finite element analysis of debonded sandwich columns and panels showed that the major crack displacement is opening (mode I). The tendency of the crack tip to first open and then close after buckling of the face sheet is believed to be due to the formation of an eccentric load path at the onset of buckling. The fracture mechanics analysis of debonded sandwich panels showed that the energy release rate is much higher in the direction perpendicular to the applied load than along the loading direction, and exceeds the measured toughness value in the transverse direction. This explains the experimental observation that a debond embedded in a sandwich panel tends to propagate in the transverse direction.
Title: | Local buckling and debond propagation in sandwich columns and panels. |
5663 views
31 downloads |
---|---|---|
Name(s): |
Aviles, Francis. Florida Atlantic University, Degree grantor Carlsson, Leif A., Thesis advisor College of Engineering and Computer Science Department of Ocean and Mechanical Engineering |
|
Type of Resource: | text | |
Genre: | Electronic Thesis Or Dissertation | |
Issuance: | monographic | |
Date Issued: | 2005 | |
Publisher: | Florida Atlantic University | |
Place of Publication: | Boca Raton, Fla. | |
Physical Form: | application/pdf | |
Extent: | 179 p. | |
Language(s): | English | |
Summary: | The local buckling failure mechanism and subsequent debond propagation in sandwich columns and panels with composite face sheets containing a face-to-core debond is experimentally, analytically, and numerically analyzed. The experimental investigation is based on a comprehensive test program to examine local buckling failure and fracture toughness of sandwich specimens consisting of glass/epoxy face sheets over various density PVC foams and a balsa wood core. Elastic foundation and finite element models are developed for prediction of the local buckling load of sandwich columns and panels containing an implanted debond at the face/core interface. Nonlinear finite element analysis was conducted to investigate debond propagation in the post-buckling region. Overall, model predictions were in agreement with experimental results. The buckling load was found to decrease with reduced face sheet stiffness, reduced core modulus, and increased debond length. Sandwich panels with circular debonds were more resistant to local buckling than those with square debonds of the same characteristic size. Circular debonds of 50 mm diameter and square debonds of 45 mm side length established the threshold for local buckling failure. Nonlinear finite element analysis of debonded sandwich columns and panels showed that the major crack displacement is opening (mode I). The tendency of the crack tip to first open and then close after buckling of the face sheet is believed to be due to the formation of an eccentric load path at the onset of buckling. The fracture mechanics analysis of debonded sandwich panels showed that the energy release rate is much higher in the direction perpendicular to the applied load than along the loading direction, and exceeds the measured toughness value in the transverse direction. This explains the experimental observation that a debond embedded in a sandwich panel tends to propagate in the transverse direction. | |
Identifier: | 9780496955831 (isbn), 12123 (digitool), FADT12123 (IID), fau:9033 (fedora) | |
Collection: | FAU Electronic Theses and Dissertations Collection | |
Note(s): |
College of Engineering and Computer Science Thesis (Ph.D.)--Florida Atlantic University, 2005. |
|
Subject(s): |
Buckling (Mechanics) Sandwich construction Fracture mechanics Diffusion bonding (Metals) Strength of materials |
|
Held by: | Florida Atlantic University Libraries | |
Sublocation: | Digital Library | |
Persistent Link to This Record: | http://purl.flvc.org/fau/fd/FADT12123 | |
Use and Reproduction: | Copyright © is held by the author, with permission granted to Florida Atlantic University to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder. | |
Use and Reproduction: | http://rightsstatements.org/vocab/InC/1.0/ | |
Host Institution: | FAU | |
Is Part of Series: | Florida Atlantic University Digital Library Collections. |