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Pultruded GFRP Reinforcing Bars Using Nanomodified Vinyl Ester
Shreya Vemuganti1, Rahulreddy Chennareddy1, Amr Riad2
1Department of Civil, Construction and Environmental Engineering, University of New Mexico, Albuquerque, NM 87131-0001, USA.
Materials (Basel, Switzerland)
|December 17, 2020
Summary
Nanomodified glass fiber-reinforced polymer (GFRP) bars show significantly enhanced horizontal shear strength. This breakthrough expands the use of GFRP in demanding civil infrastructure applications.
Area of Science:
- Materials Science
- Civil Engineering
- Polymer Science
Background:
- Glass fiber-reinforced polymer (GFRP) reinforcing bars possess limited shear strength, restricting their use in high-demand civil infrastructure.
- Applications like concrete reinforcing dowels require enhanced shear performance for structural integrity.
Purpose of the Study:
- To improve the horizontal shear strength of GFRP bars through nanomodification of vinyl ester resin.
- To investigate the effects of functionalized multiwalled carbon nanotubes (MWCNTs) on GFRP bar properties.
Main Methods:
- Optimized MWCNT content in vinyl ester resin using viscosity and SEM.
- Fabricated nanomodified GFRP bars via pultrusion.
- Evaluated tensile and shear strength using longitudinal tension and short beam shear tests.
Main Results:
- Horizontal shear strength increased by 111%; tensile strength improved by 20%.
- Eliminated typical broom failure in GFRP bars by incorporating MWCNTs.
- Confirmed bar quality and chemical bonding via DSC, FTIR, and fiber volume fraction analysis.
Conclusions:
- Nanomodification of vinyl ester resin significantly boosts GFRP bar shear strength.
- The developed pultrusion process enables broader GFRP application in civil infrastructure.
- This advancement addresses limitations in GFRP shear performance for structural components.
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