Shear Modulus of Standard Pultruded Fiber Reinforced Plastic Material
Publication: Journal of Composites for Construction
Volume 8, Issue 2
Abstract
Research to determine the shear modulus of standard pultruded fiber reinforced plastic (FRP) material is reviewed and appraised. It is found that different test methods have given shear moduli data in the range from 1.3 to 5.1 GPa, with varying degrees of scatter. Pultruded material is comprised of alternate layers of two distinct glass reinforcement types. By applying micromechanical modeling, it is shown that the in-plane shear modulus of the continuous unidirectional rovings layer is similar to that of the continuous filament (or strand) mat layer, and that these layer moduli, generally, lie in the range 3.5 to 4.8 GPa (depending on fiber volume fraction). This finding indicates that the significant difference (>1.3 times) between the in-plane (3 GPa or less) and the St. Venant torsion (always >4 GPa) shear moduli is likely to be due to the experimental test procedures and the physical interpretation of shearing, rather than the layer construction of the material. For structural profiles, it is seen that the shear modulus of 3 GPa in company design manuals is often less than measured. Researchers require correlated elastic constant data if elastic deflections and instability loads for structural members can be accurately predicted using elastic theory. Further work is, therefore, recommended to establish standard test and analytical methods for the determination of shear moduli of pultruded FRP material.
Get full access to this article
View all available purchase options and get full access to this article.
References
Akasaka, T.(1974). “A practical method of evaluating the isotropic constants of glass mat reinforced plastic.” Compos. Mater. Struct. (in Japanese), 3, 21–22.
Anon. (1989). EXTREN design manual, Strongwell, Bristol, Va.
Anon. (1995). Fiberline design manual for structural profiles in composite materials, Fiberline Composites A/S, Kolding, Denmark.
Anon. (2001). The new and improved Pultex® pultrusion Global design manual of pultex standard and custom fiber reinforced polymer structural profiles, Vol. 3 Revision 1, Creative Pultrusions Inc., Alum Bank, Pa.
Bank, L. C.(1987). “Shear coefficients for thin-walled composite beams.” Compos. Struct., 8, 47–61.
Bank, L. C.(1989). “Flexural and shear moduli of full-section fiber reinforced plastic pultruded beams.” J. Test. Eval., 17(1), 40–45.
Bank, L. C.(1990). “Shear properties of pultruded glass fiber reinforced plastic materials.” J. Mater. Civ. Eng., 2(2), 118–122.
Barbero, E. J. (1999). Introduction to composite materials, Taylor and Francis, Philadelphia, Pa.
Barbero, E. J., and Raftoyiannis, I. G.(1993). “Local buckling of fiber reinforced plastic beams and columns.” J. Mater. Civ. Eng., 5(3), 339–355.
Case, J., and Chilver, A. H. (1959). Strength of materials, Edward Arnold, London.
Clarke, J. L., (Ed.). (1996). Structural design of polymer composites—EUROCOMP Design code and handbook, E&FN Spon, London.
“Force 800.” (2003). FibreForce Composites, 〈http://www.fibreforce.u-net.com/〉 (Mar. 31).
Halpin, J. C., and Tsai S. W. (1967). “Environmental factors in composite material design.” Air Force Materials Laboratory (AFML) Ref. TR67-423, AFML, Dayton, Ohio.
Hancox, N. L., and Meyer, R. M. (1994). Design data for reinforced plastics: A guide for engineers and designers, Chapman and Hall, London.
Hull, D. (1981). An introduction to composite materials, Cambridge University Press, Cambridge, U.K.
Johnson, A. F. (1987). “Engineering design properties of glass-reinforced plastic.” A joint British Plastics Federation and National Physical Laboratory report, British Plastics Federation, London.
Lane, A. (2002). “An experimental investigation of buckling mode interaction in pultruded fiber reinforced plastic columns.” PhD thesis, Univ. of Warwick, U.K.
Mottram, J. T. (1991). “Structural properties of a pultruded E-glass fiber-reinforced polymeric I beam.” Proc., 6th Int. Conf. on Composite Structures, Elsevier Applied Science, 1–28.
Omidvar, B.(1998). “Shear coefficient in orthotropic thin-walled composite beams.” J. Compos. Constr., 2(1), 46–56.
Quinn, J. A. (1998). Composites—Design manual, 2nd Ed., James Quinn Associates, Liverpool, U.K.
Quinn, J. A., and Randall, J. E. (1990). “Compliance of composite reinforcement materials.” Proc., 4th Int. Conf. FRC’90 Fibre Reinforced Composites, IMechE, London, 105–112.
Roberts, T. M., and Al-Ubaidi, H.(2002). “Flexural and torsional properties of pultruded fiber reinforced plastic I profiles.” J. Compos. Constr., 6(1), 28–34.
Smith, C. S. (1990). Design of marine structures in composite materials, Elsevier, London.
Sonti, S. S., and Barbero, E. J.(1996). “Material characterization of pultruded laminates and shapes.” J. Reinf. Plast. Compos., 15(7), 701–717.
Sonti, S. S., Barbero, E. J., and Winegardner, T.(1995). “Determination of shear properties for reinforced plastic pultruded composites.” J. Reinf. Plast. Compos., 14(4), 390–401.
Steffen, R. E. (1998). “Behavior and design of fiber-reinforced polymeric composite equal-leg angle struts.” PhD thesis, Georgia Institute of Technology, Atlanta.
Timoshenko, S. P., and Goodier, J. N. (1988). Theory of elasticity, 3rd Ed., McGraw-Hill, New York.
Turvey, G. J.(1998). “Torsion tests on pultruded glass-reinforced plastic sheets.” Compos. Sci. Technol., 58(8), 1343–1351.
Turvey, G. J. (2002). “Pultruded glass-reinforced plastic frames: Simple (conservative) approach to design: A rational alternative and research needs for improved design.” Proc., Int. Workshop on Composites in Construction: A Reality, ASCE, Reston, Va. 258–266.
Ye, B. S., Svenson, A. L., and Bank, L. C.(1995). “Mass and volume fraction properties of pultruded glass-fiber-reinforced composites.” Composites, 26(10), 725–731.
Zureick, A., and Scott, D.(1997). “Short-term behavior and design of fiber-reinforced polymeric slender members under axial compression.” J. Compos. Constr., 1(4), 140–149.
Information & Authors
Information
Published In
Copyright
Copyright © 2004 American Society of Civil Engineers.
History
Received: Feb 15, 2002
Accepted: Feb 25, 2003
Published online: Mar 15, 2004
Published in print: Apr 2004
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.