Measurement of the Timoshenko Shear Stiffness. I: Effect of Warping

Fiber-reinforced polymer (FRP) composite beams are increasingly finding use in construction. Due to their lower stiffness relative to steel sections, design of FRP structures is usually deflection controlled. Furthermore, shear deformation can be significant in FRP beams, thus, requiring the use of the Timoshenko beam theory to estimate deflections. However, Timoshenko shear stiffness can be difficult to measure. Part of the measurement error is attributed to shear warping effects. It has been hypothesized that warping restrains at loading points and supports increase the apparent shear stiffness to a degree that is significant at relatively short spans. In this paper, influence of warping on short to moderate length FRP beams under various types of loading and boundary conditions is considered using finite-element analysis. In particular, a commercially available thin-walled FRP beam was studied. Results suggest that warping has a negligible effect for thin-walled beams at reasonable spans. Conversely, the effective shear stiffness is found to decrease at shorter span lengths. This is the first of 2 papers in a series.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/10900268
• Supplemental Notes:
  • Abstract reprinted with permission from ASCE
• Authors:
  • Hayes, Michael D
  • Lesko, John J
• Publication Date: 2007-5

Language

• English

Media Info

• Media Type: Print
• Features: Figures; Photos; References; Tables;
• Pagination: pp 336-342
• Serial:
  • Journal of Composites for Construction
  • Volume: 11
  • Issue Number: 3
  • Publisher: American Society of Civil Engineers
  • ISSN: 1090-0268
  • EISSN: 1943-5614
  • Serial URL: http://ascelibrary.org/journal/jccof2

Subject/Index Terms

• TRT Terms: Beams; Composite structures; Deformation; Fiber reinforced plastics; Finite element method; Shear modulus; Shear properties; Shear strength; Structural members
• Identifier Terms: Timoshenko's Equation
• Uncontrolled Terms: Timoshenko beams; Warping
• Subject Areas: Bridges and other structures; Design; Highways; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 01051324
• Record Type: Publication
• Files: TRIS
• Created Date: Jun 10 2007 1:17PM