Development of a Polymer Wear Surface for a FRP Composite Bridge Deck

1. Development of a Polymer Wear Surface for a FRP Composite Bridge Deck D.C. Haeberle, L.A. Harris, J.J. Lesko, J.S. Riffle, and T.E. Cousins Materials Response Group Virginia Tech

3. Strongwell Bridge Deck

4. Field Application

5. Presentation Overview Project Description Sample Preparation Tests Conducted Discussion of Results Conclusions

6. Project Description Evaluation of the effects of sample variables on the properties of a polymer wear surface produced on a pultruded glass-reinforced isophthalic polyester surface for bridge deck applications.

7. Sample Parameters Resins Derakane 411-350 Vinyl Ester Derakane 8084 Toughened Vinyl Ester Aquathane Polyurethane Thickness 1 Layer (about 1/16 in.) 2 Layers (about 3/16 in.) 3 Layers (about 5/16 in.)

8. Sample Components

9. Sample Preparation Step 1: Perform plate surface preparation Step 2: Apply thick coat of polymer resin Step 3: Pour aggregate over uncured resin Step 4: Allow resin to cure at room temperature Step 5: Brush off loose aggregate Step 6: Repeat steps 2-5 until for each additional layer Step 7: Apply a top coat of polymer resin

10. Sample Properties

11. Percent Conversion of Vinyl Ester

12. Tensile Rupture Strength Test VTRC test method Modified & improved for Instron Testing 200 psi strength desired

13. Tensile Rupture Strength Results

14. Failed Specimens Highly variable results due to brittle nature of the material Adhesive, Cohesive, and Substrate Failures

15. Weigh Station Deck Model: Vertical Deflection

16. Strain-to-Failure Test ASTM D-790 4-point bend test Wear surface on the tensile side Strain measured with an extensometer mounted to wear surface >0.2% strain-to-failure desired

17. Strain-to-Failure Results: Resin Comparison

18. Strain-to-Failure Results: Surface Comparison

19. Failed Specimen:Acetone Wash Crack causes immediate debond of wear surface from composite plate Brittle fracture behavior observed, cracks propagate through resin and aggregate (good particle adhesion)

20. Failed Specimen:Grit-Blasted Crack causes no immediate debond of the wear surface from the composite plate Crack slowly propagates under the surface veil of the composite substrate

21. Strain-to-Failure Results: Temperature Comparison

22. DMA Results

23. Conclusions Toughened vinyl ester provides 30% higher strain-to-failure but 90% less adhesion to the composite surface (acetone washed) Grit-blasting essential for required adhesion and prevention of catastrophic debonding upon surface fracture Smooth round aggregate provides higher strain-to-failure than the sharp quartz aggregate

24. Troutville Weigh Station

25. Preliminary Nanoindentation of a Composite Fiber Pultruded Vinyl Ester Matrix/Carbon Fiber/G� Fiber Sizing Digital Instruments Nanoscope with Hysitron Indentor

26. Load - Deflection Curve

27. UV Testing Strategy Outdoor/Indoor Exposure of Low Cost Vinyl Ester Matrix Composites Determine if a Relationship between Indoor and Outdoor Exposure Exists and Develop that Relationship Determine the Effects of Exposure on Tensile Strength

28. UV Exposure Equipment

29. Sunlight Spectra

30. Current Work in the Development and Implementation of Low Cost Composites for Infrastructure Applications David Haeberle MRG Group Meeting February 17, 2000